Case Reports

Total hip arthroplasty (THA) is one of the most successful orthopedic interventions performed today in terms of pain relief, cost effectiveness, and clinical outcomes.¹ As a definitive treatment for end-stage arthritis of the hip, more than 330,000 procedures are performed in the Unites States each year. The number performed is growing by > 5% per year and is predicted to double by 2030, partly due to patients living longer, older individuals seeking a higher level of functionality than did previous generations, and better access to health care.^2,3

The THA procedure also has become increasingly common in a younger population for posttraumatic fractures and conditions that lead to early-onset secondary arthritis, such as avascular necrosis, juvenile rheumatoid arthritis, hip dysplasia, Perthes disease, and femoroacetabular impingement.⁴ Younger patients are more likely to need a revision. According to a study by Evans and colleagues using available arthroplasty registry data, about three-quarters of hip replacements last 15 to 20 years, and 58% of hip replacements last 25 years in patients with osteoarthritis.⁵

For decades, the THA procedure of choice has been a standard posterior approach (PA). The PA was used because it allowed excellent intraoperative exposure and was applicable to a wide range of hip problems.⁶ In the past several years, modified muscle-sparing surgical approaches have been introduced. Two performed frequently are the mini PA (MPA) and the direct anterior approach (DAA).

The MPA is a modification of the PA. Surgeons perform the THA through a small incision without cutting the abductor muscles that are critical to hip stability and gait. A study published in 2010 concluded that the MPA was associated with less pain, shorter hospital length of stay (LOS) (therefore, an economic saving), and an earlier return to walking postoperatively.⁷

The DAA has been around since the early days of THA. Carl Hueter first described the anterior approach to the hip in 1881 (referred to as the Hueter approach). Smith-Peterson is frequently credited with popularizing the DAA technique during his career after publishing his first description of the approach in 1917.⁸ About 10 years ago, the DAA showed a resurgence as another muscle-sparing alternative for THAs. The DAA is considered to be a true intermuscular approach that preserves the soft tissues around the hip joint, thereby preserving the stability of the joint.^9-11 The optimal surgical approach is still the subject of debate.

We present a male with right hip end-stage degenerative joint disease (DJD) and review some medical literature. Although other approaches to THA can be used (lateral, anterolateral), the discussion focuses on 2 muscle-sparing approaches performed frequently, the MPA and the DAA, and can be of value to primary care practitioners in their discussion with patients.

Case Presentation

A 61-year-old male patient presented with progressive right hip pain. At age 37, he had a left THA via a PA due to hip dysplasia and a revision on the same hip at age 55 (the polyethylene liner was replaced and the cobalt chromium head was changed to ceramic), again through a PA. An orthopedic clinical evaluation and X-rays confirmed end-stage DJD of the right hip (Figure). He was informed to return to plan an elective THA when the “bad days were significantly greater than the good days” and/or when his functionality or quality of life was unacceptable. The orthopedic surgeon favored an MPA but offered a hand-off to colleagues who preferred the DAA. The patient was given information to review.

Discussion

No matter which approach is used, one study concluded that surgeons who perform > 50 hip replacements each year have better overall outcomes.¹²

The MPA emerged in the past decade as a muscle-sparing modification of the PA. The incision length (< 10 cm) is the simplest way of categorizing the surgery as an MPA. However, the amount of deep surgical dissection is a more important consideration for sparing muscle (for improved postoperative functionality, recovery, and joint stability) due to the gluteus maximus insertion, the quadratus femoris, and the piriformis tendons being left intact.^13-16

Conclusions

THA is one of the most successful surgical procedures performed today. Patients desire hip pain relief and a return to function with as little interruption in their life as possible. Additionally, health care systems and insurers require THA procedures to be as efficient and cost-effective as possible. The debate regarding the most effective or preferable approach for THA continues. Although some prospective RCTs found that patients who underwent the DAA had objectively faster recovery than patients who had the MPA, it is also acknowledged that the results were dependent on surgeons who are very skilled in performing DAAs. The hope of both approaches is to get the individual moving as quickly and safely as possible to avoid a cascade of deterioration in the postoperative period. Factors other than the surgical approach, including patient selection, surgical volume and experience, careful preoperative assessments, attentive pain management, and rapid rehabilitation protocols, may be just as important as to which procedure is performed.³⁰ The final decision should still be dependent on the patient-surgeon relationship and informed decision making.

In this case, the patient reviewed all the information he was given and independently researched the 2 procedures over many months. Ultimately, he decided to undergo a right THA via the DAA.

Total hip arthroplasty (THA) is one of the most successful orthopedic interventions performed today in terms of pain relief, cost effectiveness, and clinical outcomes.¹ As a definitive treatment for end-stage arthritis of the hip, more than 330,000 procedures are performed in the Unites States each year. The number performed is growing by > 5% per year and is predicted to double by 2030, partly due to patients living longer, older individuals seeking a higher level of functionality than did previous generations, and better access to health care.^2,3

The THA procedure also has become increasingly common in a younger population for posttraumatic fractures and conditions that lead to early-onset secondary arthritis, such as avascular necrosis, juvenile rheumatoid arthritis, hip dysplasia, Perthes disease, and femoroacetabular impingement.⁴ Younger patients are more likely to need a revision. According to a study by Evans and colleagues using available arthroplasty registry data, about three-quarters of hip replacements last 15 to 20 years, and 58% of hip replacements last 25 years in patients with osteoarthritis.⁵

For decades, the THA procedure of choice has been a standard posterior approach (PA). The PA was used because it allowed excellent intraoperative exposure and was applicable to a wide range of hip problems.⁶ In the past several years, modified muscle-sparing surgical approaches have been introduced. Two performed frequently are the mini PA (MPA) and the direct anterior approach (DAA).

The MPA is a modification of the PA. Surgeons perform the THA through a small incision without cutting the abductor muscles that are critical to hip stability and gait. A study published in 2010 concluded that the MPA was associated with less pain, shorter hospital length of stay (LOS) (therefore, an economic saving), and an earlier return to walking postoperatively.⁷

The DAA has been around since the early days of THA. Carl Hueter first described the anterior approach to the hip in 1881 (referred to as the Hueter approach). Smith-Peterson is frequently credited with popularizing the DAA technique during his career after publishing his first description of the approach in 1917.⁸ About 10 years ago, the DAA showed a resurgence as another muscle-sparing alternative for THAs. The DAA is considered to be a true intermuscular approach that preserves the soft tissues around the hip joint, thereby preserving the stability of the joint.^9-11 The optimal surgical approach is still the subject of debate.

We present a male with right hip end-stage degenerative joint disease (DJD) and review some medical literature. Although other approaches to THA can be used (lateral, anterolateral), the discussion focuses on 2 muscle-sparing approaches performed frequently, the MPA and the DAA, and can be of value to primary care practitioners in their discussion with patients.

Case Presentation

A 61-year-old male patient presented with progressive right hip pain. At age 37, he had a left THA via a PA due to hip dysplasia and a revision on the same hip at age 55 (the polyethylene liner was replaced and the cobalt chromium head was changed to ceramic), again through a PA. An orthopedic clinical evaluation and X-rays confirmed end-stage DJD of the right hip (Figure). He was informed to return to plan an elective THA when the “bad days were significantly greater than the good days” and/or when his functionality or quality of life was unacceptable. The orthopedic surgeon favored an MPA but offered a hand-off to colleagues who preferred the DAA. The patient was given information to review.

Discussion

No matter which approach is used, one study concluded that surgeons who perform > 50 hip replacements each year have better overall outcomes.¹²

The MPA emerged in the past decade as a muscle-sparing modification of the PA. The incision length (< 10 cm) is the simplest way of categorizing the surgery as an MPA. However, the amount of deep surgical dissection is a more important consideration for sparing muscle (for improved postoperative functionality, recovery, and joint stability) due to the gluteus maximus insertion, the quadratus femoris, and the piriformis tendons being left intact.^13-16

Conclusions

THA is one of the most successful surgical procedures performed today. Patients desire hip pain relief and a return to function with as little interruption in their life as possible. Additionally, health care systems and insurers require THA procedures to be as efficient and cost-effective as possible. The debate regarding the most effective or preferable approach for THA continues. Although some prospective RCTs found that patients who underwent the DAA had objectively faster recovery than patients who had the MPA, it is also acknowledged that the results were dependent on surgeons who are very skilled in performing DAAs. The hope of both approaches is to get the individual moving as quickly and safely as possible to avoid a cascade of deterioration in the postoperative period. Factors other than the surgical approach, including patient selection, surgical volume and experience, careful preoperative assessments, attentive pain management, and rapid rehabilitation protocols, may be just as important as to which procedure is performed.³⁰ The final decision should still be dependent on the patient-surgeon relationship and informed decision making.

In this case, the patient reviewed all the information he was given and independently researched the 2 procedures over many months. Ultimately, he decided to undergo a right THA via the DAA.

Total hip arthroplasty (THA) is one of the most successful orthopedic interventions performed today in terms of pain relief, cost effectiveness, and clinical outcomes.¹ As a definitive treatment for end-stage arthritis of the hip, more than 330,000 procedures are performed in the Unites States each year. The number performed is growing by > 5% per year and is predicted to double by 2030, partly due to patients living longer, older individuals seeking a higher level of functionality than did previous generations, and better access to health care.^2,3

The THA procedure also has become increasingly common in a younger population for posttraumatic fractures and conditions that lead to early-onset secondary arthritis, such as avascular necrosis, juvenile rheumatoid arthritis, hip dysplasia, Perthes disease, and femoroacetabular impingement.⁴ Younger patients are more likely to need a revision. According to a study by Evans and colleagues using available arthroplasty registry data, about three-quarters of hip replacements last 15 to 20 years, and 58% of hip replacements last 25 years in patients with osteoarthritis.⁵

For decades, the THA procedure of choice has been a standard posterior approach (PA). The PA was used because it allowed excellent intraoperative exposure and was applicable to a wide range of hip problems.⁶ In the past several years, modified muscle-sparing surgical approaches have been introduced. Two performed frequently are the mini PA (MPA) and the direct anterior approach (DAA).

The MPA is a modification of the PA. Surgeons perform the THA through a small incision without cutting the abductor muscles that are critical to hip stability and gait. A study published in 2010 concluded that the MPA was associated with less pain, shorter hospital length of stay (LOS) (therefore, an economic saving), and an earlier return to walking postoperatively.⁷

The DAA has been around since the early days of THA. Carl Hueter first described the anterior approach to the hip in 1881 (referred to as the Hueter approach). Smith-Peterson is frequently credited with popularizing the DAA technique during his career after publishing his first description of the approach in 1917.⁸ About 10 years ago, the DAA showed a resurgence as another muscle-sparing alternative for THAs. The DAA is considered to be a true intermuscular approach that preserves the soft tissues around the hip joint, thereby preserving the stability of the joint.^9-11 The optimal surgical approach is still the subject of debate.

We present a male with right hip end-stage degenerative joint disease (DJD) and review some medical literature. Although other approaches to THA can be used (lateral, anterolateral), the discussion focuses on 2 muscle-sparing approaches performed frequently, the MPA and the DAA, and can be of value to primary care practitioners in their discussion with patients.

Case Presentation

A 61-year-old male patient presented with progressive right hip pain. At age 37, he had a left THA via a PA due to hip dysplasia and a revision on the same hip at age 55 (the polyethylene liner was replaced and the cobalt chromium head was changed to ceramic), again through a PA. An orthopedic clinical evaluation and X-rays confirmed end-stage DJD of the right hip (Figure). He was informed to return to plan an elective THA when the “bad days were significantly greater than the good days” and/or when his functionality or quality of life was unacceptable. The orthopedic surgeon favored an MPA but offered a hand-off to colleagues who preferred the DAA. The patient was given information to review.

Discussion

No matter which approach is used, one study concluded that surgeons who perform > 50 hip replacements each year have better overall outcomes.¹²

The MPA emerged in the past decade as a muscle-sparing modification of the PA. The incision length (< 10 cm) is the simplest way of categorizing the surgery as an MPA. However, the amount of deep surgical dissection is a more important consideration for sparing muscle (for improved postoperative functionality, recovery, and joint stability) due to the gluteus maximus insertion, the quadratus femoris, and the piriformis tendons being left intact.^13-16

Conclusions

THA is one of the most successful surgical procedures performed today. Patients desire hip pain relief and a return to function with as little interruption in their life as possible. Additionally, health care systems and insurers require THA procedures to be as efficient and cost-effective as possible. The debate regarding the most effective or preferable approach for THA continues. Although some prospective RCTs found that patients who underwent the DAA had objectively faster recovery than patients who had the MPA, it is also acknowledged that the results were dependent on surgeons who are very skilled in performing DAAs. The hope of both approaches is to get the individual moving as quickly and safely as possible to avoid a cascade of deterioration in the postoperative period. Factors other than the surgical approach, including patient selection, surgical volume and experience, careful preoperative assessments, attentive pain management, and rapid rehabilitation protocols, may be just as important as to which procedure is performed.³⁰ The final decision should still be dependent on the patient-surgeon relationship and informed decision making.

In this case, the patient reviewed all the information he was given and independently researched the 2 procedures over many months. Ultimately, he decided to undergo a right THA via the DAA.

Valproic acid (VPA) and its derivative, divalproex (DVP) are prescribed for a variety of indications, commonly for seizure control in patients with epilepsy, mood stabilization in patients with bipolar disorder, and migraine prophylaxis. Gastrointestinal distress and sedation are among the most reported adverse effects (AEs) with DVP therapy.¹ Although serious hepatic and hematologic AEs are rare, monitoring is still recommended. DVP can cause various hematologic dyscrasias, the most common being thrombocytopenia.^1,2 Neutropenia and leukopenia have been reported in isolated cases, most occurring in pediatric patients or patients with epilepsy.^3-14

Several case reports of DVP-related neutropenia (absolute neutrophil count [ANC] < 1.50 10³/mcL) and leukopenia (white blood cell count [WBC] < 4.0 10³/mcL) were reviewed during our literature search, some caused by DVP monotherapy; others were thought to be related to concomitant use of DVP and another drug.^15-25 Quetiapine was the antipsychotic most commonly implicated in causing hematologic abnormalities when combined with DVP. We report a case of neutropenia and leukopenia that presented after a cross taper from quetiapine to DVP for the treatment of borderline personality disorder (BPD).

Although no medications have been approved by the US Food and Drug Administration (FDA) for the treatment of BPD, mood stabilizers, including DVP, have literature to support their use for the treatment of affective dysregulation and impulsive behavioral dyscontrol.^26-28 A therapeutic range for DVP in the treatment of BPD has not been defined; therefore, for this case report, the generally accepted range of 50 to 100 µg/mL will be considered therapeutic.¹

Case Presentation

A 34-year-old male patient presented to the mental health clinic pharmacist reporting that his current psychotropic medication regimen was not effective. His medical history included posttraumatic stress disorder (PTSD), opioid use disorder, alcohol use disorder, stimulant use disorder, cannabis use, BPD, hypertension, hyperlipidemia, prediabetes, gastroesophageal reflex disease, and a pulmonary nodule. On initial presentation, the patient was prescribed buprenorphine 24 mg/naloxone 6 mg, quetiapine 400 mg, duloxetine 120 mg, and prazosin 15 mg per day. At the time of pharmacy consultation, last reported alcohol or nonprescribed opioid use was about 6 months prior, and methamphetamine use about 1 month prior, with ongoing cannabis use. The patient had a history of participating in cognitive processing therapy, dialectical behavior therapy (DBT), and residential treatment for both PTSD and substance use. Additionally, he was actively participating in contingency management for stimulant use disorder and self-management and recovery training group.

The patient reported ongoing mood lability, hypervigilance, and oversedation with current psychotropic regimen. The prescriber of his medication for opioid use disorder also reported the patient experienced labile mood, impulsive behavior, and anger outbursts. In the setting of intolerability due to oversedation with quetiapine, cardiometabolic risk, and lack of clear indication for use, the patient and health care practitioner (HCP) agreed to taper quetiapine and initiate a trial of DVP for affective dysregulation and impulsive-behavioral dyscontrol. To prevent cholinergic rebound and insomnia with abrupt discontinuation of quetiapine, DVP and quetiapine were cross tapered. The following cross taper was prescribed: quetiapine 300 mg and DVP 500 mg per day for week 1; quetiapine 200 mg and DVP 500 mg per day for week 2; quetiapine 100 mg and DVP 1000 mg per day for week 3; quetiapine 50 mg and DVP 1000 mg per day for week 4; followed by DVP 1000 mg per day and discontinuation of quetiapine.

During a 4-week follow-up appointment, the patient reported appropriate completion of cross taper but stopped taking the DVP 3 days prior to the appointment due to self-reported lack of efficacy. For this reason, serum VPA level was not obtained. After discussion with his HCP, the patient restarted DVP 1000 mg per day without retitration with plans to get laboratory tests in 1 week. The next week, laboratory tests were notable for VPA level 28.74 (reference range, 50-100) µg/mL, low WBC 3.51 (reference range, 4.00-10.00) 10³/mcL, platelets 169 (reference range, 150-420) 10³/mcL, and low ANC 1.00 (reference range, 1.50-7.40) 10³/mcL (Table). This raised clinical concern as the patient had no history of documented neutropenia or leukopenia, with most recent complete blood count (CBC) prior to DVP initiation 3 months earlier while prescribed quetiapine.

Discussion

Our case report describes isolated neutropenia and leukopenia that developed after a cross taper from quetiapine to DVP. Hematologic abnormalities resolved after discontinuation of DVP, suggesting a likely correlation. DVP has a well-established, dose-related prevalence of thrombocytopenia occurring in up to 27% of patients.¹ Fewer case reports exist on neutropenia and leukopenia. DVP-induced neutropenia is thought to be a result of direct bone marrow suppression, whereas the more commonly occurring blood dyscrasia, thrombocytopenia, is thought to be caused by an antibody-mediated destruction of platelets.⁶

Management of DVP-induced thrombocytopenia is often dependent on the severity of the reaction. In mild-to-moderate cases, intervention may not be necessary as thrombocytopenia has been shown to resolve without adjustment to DVP therapy.¹ In more severe or symptomatic cases, dose reduction or discontinuation of the offending agent is recommended, typically resulting in resolution shortly following pharmacologic intervention.

Guidance on the management of other drug-induced hematologic abnormalities, such as neutropenia and leukopenia are not as well established. A 2019 systematic review of idiosyncratic drug-induced neutropenia suggested that continuing the offending drug with strict monitoring could be considered in cases of mild neutropenia. In cases of moderate neutropenia, the author suggests temporary cessation of the drug and reinstatement once neutrophil count normalizes and definitive cessation of the drug in severe cases.³⁰

In our case, continuing the offending agent with close monitoring was considered, similar to the well-established management of clozapine-induced neutropenia. However, due to the concern that the ANC was bordering moderate neutropenia in the absence of a therapeutic VPA level as well as a significant reduction in platelets, although not meeting criteria for thrombocytopenia, the decision was made to err on the side of caution and discontinue the most likely offending agent.

It is important to highlight that DVP was replacing quetiapine in the form of a cross taper. Quetiapine is structurally similar to clozapine. While clozapine has strict monitoring requirements related to neutropenia, blood dyscrasias with quetiapine therapy are rare. Quetiapine-induced hematologic abnormalities may be due to direct toxicity or to an immune-mediated mechanism, leading to bone marrow suppression.²⁰ Case reports documenting blood dyscrasias with the combination of DVP and quetiapine were identified during literature review.^15-19 Despite these case reports, we believe DVP was the primary offending agent in our case as the patient’s last dose of quetiapine was 2 weeks before obtaining the abnormal CBC. There was no history of blood dyscrasias with quetiapine monotherapy; however, the effect of the combination of DVP and quetiapine is unknown as no CBC was obtained during the cross-taper period.

Although there are no FDA-approved medications for the treatment of BPD, mood stabilizers, including DVP, have some research to support their use for the treatment of affective dysregulation and impulsive-behavioral dyscontrol.^26-28 In our case, DVP was selected due to the evidence for use in BPD and ability to assess adherence with therapeutic monitoring. Although polypharmacy is a concern in patients with BPD, in our case we believed that the patient’s ongoing mood lability and impulsive behaviors warranted pharmacologic intervention. Additionally, DVP provided an advantage in its ability to quickly titrate to therapeutic dose when compared with lamotrigine and a lower risk of cognitive AEs when compared with topiramate.

Conclusions

To our knowledge, this case report demonstrates the first published case of neutropenia and leukopenia related to DVP therapy for the treatment of BPD. Routine CBC monitoring is recommended with DVP therapy, and our case highlights the importance of evaluating for not only thrombocytopenia, but also other blood dyscrasias during the titration phase even in the absence of a therapeutic VPA level. Further studies are warranted to determine incidence of DVP-related neutropenia and leukopenia and to evaluate the safety of continuing DVP in cases of mild-to-moderate neutropenia with close monitoring.

Valproic acid (VPA) and its derivative, divalproex (DVP) are prescribed for a variety of indications, commonly for seizure control in patients with epilepsy, mood stabilization in patients with bipolar disorder, and migraine prophylaxis. Gastrointestinal distress and sedation are among the most reported adverse effects (AEs) with DVP therapy.¹ Although serious hepatic and hematologic AEs are rare, monitoring is still recommended. DVP can cause various hematologic dyscrasias, the most common being thrombocytopenia.^1,2 Neutropenia and leukopenia have been reported in isolated cases, most occurring in pediatric patients or patients with epilepsy.^3-14

Several case reports of DVP-related neutropenia (absolute neutrophil count [ANC] < 1.50 10³/mcL) and leukopenia (white blood cell count [WBC] < 4.0 10³/mcL) were reviewed during our literature search, some caused by DVP monotherapy; others were thought to be related to concomitant use of DVP and another drug.^15-25 Quetiapine was the antipsychotic most commonly implicated in causing hematologic abnormalities when combined with DVP. We report a case of neutropenia and leukopenia that presented after a cross taper from quetiapine to DVP for the treatment of borderline personality disorder (BPD).

Although no medications have been approved by the US Food and Drug Administration (FDA) for the treatment of BPD, mood stabilizers, including DVP, have literature to support their use for the treatment of affective dysregulation and impulsive behavioral dyscontrol.^26-28 A therapeutic range for DVP in the treatment of BPD has not been defined; therefore, for this case report, the generally accepted range of 50 to 100 µg/mL will be considered therapeutic.¹

Case Presentation

A 34-year-old male patient presented to the mental health clinic pharmacist reporting that his current psychotropic medication regimen was not effective. His medical history included posttraumatic stress disorder (PTSD), opioid use disorder, alcohol use disorder, stimulant use disorder, cannabis use, BPD, hypertension, hyperlipidemia, prediabetes, gastroesophageal reflex disease, and a pulmonary nodule. On initial presentation, the patient was prescribed buprenorphine 24 mg/naloxone 6 mg, quetiapine 400 mg, duloxetine 120 mg, and prazosin 15 mg per day. At the time of pharmacy consultation, last reported alcohol or nonprescribed opioid use was about 6 months prior, and methamphetamine use about 1 month prior, with ongoing cannabis use. The patient had a history of participating in cognitive processing therapy, dialectical behavior therapy (DBT), and residential treatment for both PTSD and substance use. Additionally, he was actively participating in contingency management for stimulant use disorder and self-management and recovery training group.

The patient reported ongoing mood lability, hypervigilance, and oversedation with current psychotropic regimen. The prescriber of his medication for opioid use disorder also reported the patient experienced labile mood, impulsive behavior, and anger outbursts. In the setting of intolerability due to oversedation with quetiapine, cardiometabolic risk, and lack of clear indication for use, the patient and health care practitioner (HCP) agreed to taper quetiapine and initiate a trial of DVP for affective dysregulation and impulsive-behavioral dyscontrol. To prevent cholinergic rebound and insomnia with abrupt discontinuation of quetiapine, DVP and quetiapine were cross tapered. The following cross taper was prescribed: quetiapine 300 mg and DVP 500 mg per day for week 1; quetiapine 200 mg and DVP 500 mg per day for week 2; quetiapine 100 mg and DVP 1000 mg per day for week 3; quetiapine 50 mg and DVP 1000 mg per day for week 4; followed by DVP 1000 mg per day and discontinuation of quetiapine.

During a 4-week follow-up appointment, the patient reported appropriate completion of cross taper but stopped taking the DVP 3 days prior to the appointment due to self-reported lack of efficacy. For this reason, serum VPA level was not obtained. After discussion with his HCP, the patient restarted DVP 1000 mg per day without retitration with plans to get laboratory tests in 1 week. The next week, laboratory tests were notable for VPA level 28.74 (reference range, 50-100) µg/mL, low WBC 3.51 (reference range, 4.00-10.00) 10³/mcL, platelets 169 (reference range, 150-420) 10³/mcL, and low ANC 1.00 (reference range, 1.50-7.40) 10³/mcL (Table). This raised clinical concern as the patient had no history of documented neutropenia or leukopenia, with most recent complete blood count (CBC) prior to DVP initiation 3 months earlier while prescribed quetiapine.

Discussion

Our case report describes isolated neutropenia and leukopenia that developed after a cross taper from quetiapine to DVP. Hematologic abnormalities resolved after discontinuation of DVP, suggesting a likely correlation. DVP has a well-established, dose-related prevalence of thrombocytopenia occurring in up to 27% of patients.¹ Fewer case reports exist on neutropenia and leukopenia. DVP-induced neutropenia is thought to be a result of direct bone marrow suppression, whereas the more commonly occurring blood dyscrasia, thrombocytopenia, is thought to be caused by an antibody-mediated destruction of platelets.⁶

Management of DVP-induced thrombocytopenia is often dependent on the severity of the reaction. In mild-to-moderate cases, intervention may not be necessary as thrombocytopenia has been shown to resolve without adjustment to DVP therapy.¹ In more severe or symptomatic cases, dose reduction or discontinuation of the offending agent is recommended, typically resulting in resolution shortly following pharmacologic intervention.

Guidance on the management of other drug-induced hematologic abnormalities, such as neutropenia and leukopenia are not as well established. A 2019 systematic review of idiosyncratic drug-induced neutropenia suggested that continuing the offending drug with strict monitoring could be considered in cases of mild neutropenia. In cases of moderate neutropenia, the author suggests temporary cessation of the drug and reinstatement once neutrophil count normalizes and definitive cessation of the drug in severe cases.³⁰

In our case, continuing the offending agent with close monitoring was considered, similar to the well-established management of clozapine-induced neutropenia. However, due to the concern that the ANC was bordering moderate neutropenia in the absence of a therapeutic VPA level as well as a significant reduction in platelets, although not meeting criteria for thrombocytopenia, the decision was made to err on the side of caution and discontinue the most likely offending agent.

It is important to highlight that DVP was replacing quetiapine in the form of a cross taper. Quetiapine is structurally similar to clozapine. While clozapine has strict monitoring requirements related to neutropenia, blood dyscrasias with quetiapine therapy are rare. Quetiapine-induced hematologic abnormalities may be due to direct toxicity or to an immune-mediated mechanism, leading to bone marrow suppression.²⁰ Case reports documenting blood dyscrasias with the combination of DVP and quetiapine were identified during literature review.^15-19 Despite these case reports, we believe DVP was the primary offending agent in our case as the patient’s last dose of quetiapine was 2 weeks before obtaining the abnormal CBC. There was no history of blood dyscrasias with quetiapine monotherapy; however, the effect of the combination of DVP and quetiapine is unknown as no CBC was obtained during the cross-taper period.

Although there are no FDA-approved medications for the treatment of BPD, mood stabilizers, including DVP, have some research to support their use for the treatment of affective dysregulation and impulsive-behavioral dyscontrol.^26-28 In our case, DVP was selected due to the evidence for use in BPD and ability to assess adherence with therapeutic monitoring. Although polypharmacy is a concern in patients with BPD, in our case we believed that the patient’s ongoing mood lability and impulsive behaviors warranted pharmacologic intervention. Additionally, DVP provided an advantage in its ability to quickly titrate to therapeutic dose when compared with lamotrigine and a lower risk of cognitive AEs when compared with topiramate.

Conclusions

To our knowledge, this case report demonstrates the first published case of neutropenia and leukopenia related to DVP therapy for the treatment of BPD. Routine CBC monitoring is recommended with DVP therapy, and our case highlights the importance of evaluating for not only thrombocytopenia, but also other blood dyscrasias during the titration phase even in the absence of a therapeutic VPA level. Further studies are warranted to determine incidence of DVP-related neutropenia and leukopenia and to evaluate the safety of continuing DVP in cases of mild-to-moderate neutropenia with close monitoring.

Valproic acid (VPA) and its derivative, divalproex (DVP) are prescribed for a variety of indications, commonly for seizure control in patients with epilepsy, mood stabilization in patients with bipolar disorder, and migraine prophylaxis. Gastrointestinal distress and sedation are among the most reported adverse effects (AEs) with DVP therapy.¹ Although serious hepatic and hematologic AEs are rare, monitoring is still recommended. DVP can cause various hematologic dyscrasias, the most common being thrombocytopenia.^1,2 Neutropenia and leukopenia have been reported in isolated cases, most occurring in pediatric patients or patients with epilepsy.^3-14

Several case reports of DVP-related neutropenia (absolute neutrophil count [ANC] < 1.50 10³/mcL) and leukopenia (white blood cell count [WBC] < 4.0 10³/mcL) were reviewed during our literature search, some caused by DVP monotherapy; others were thought to be related to concomitant use of DVP and another drug.^15-25 Quetiapine was the antipsychotic most commonly implicated in causing hematologic abnormalities when combined with DVP. We report a case of neutropenia and leukopenia that presented after a cross taper from quetiapine to DVP for the treatment of borderline personality disorder (BPD).

Although no medications have been approved by the US Food and Drug Administration (FDA) for the treatment of BPD, mood stabilizers, including DVP, have literature to support their use for the treatment of affective dysregulation and impulsive behavioral dyscontrol.^26-28 A therapeutic range for DVP in the treatment of BPD has not been defined; therefore, for this case report, the generally accepted range of 50 to 100 µg/mL will be considered therapeutic.¹

Case Presentation

A 34-year-old male patient presented to the mental health clinic pharmacist reporting that his current psychotropic medication regimen was not effective. His medical history included posttraumatic stress disorder (PTSD), opioid use disorder, alcohol use disorder, stimulant use disorder, cannabis use, BPD, hypertension, hyperlipidemia, prediabetes, gastroesophageal reflex disease, and a pulmonary nodule. On initial presentation, the patient was prescribed buprenorphine 24 mg/naloxone 6 mg, quetiapine 400 mg, duloxetine 120 mg, and prazosin 15 mg per day. At the time of pharmacy consultation, last reported alcohol or nonprescribed opioid use was about 6 months prior, and methamphetamine use about 1 month prior, with ongoing cannabis use. The patient had a history of participating in cognitive processing therapy, dialectical behavior therapy (DBT), and residential treatment for both PTSD and substance use. Additionally, he was actively participating in contingency management for stimulant use disorder and self-management and recovery training group.

The patient reported ongoing mood lability, hypervigilance, and oversedation with current psychotropic regimen. The prescriber of his medication for opioid use disorder also reported the patient experienced labile mood, impulsive behavior, and anger outbursts. In the setting of intolerability due to oversedation with quetiapine, cardiometabolic risk, and lack of clear indication for use, the patient and health care practitioner (HCP) agreed to taper quetiapine and initiate a trial of DVP for affective dysregulation and impulsive-behavioral dyscontrol. To prevent cholinergic rebound and insomnia with abrupt discontinuation of quetiapine, DVP and quetiapine were cross tapered. The following cross taper was prescribed: quetiapine 300 mg and DVP 500 mg per day for week 1; quetiapine 200 mg and DVP 500 mg per day for week 2; quetiapine 100 mg and DVP 1000 mg per day for week 3; quetiapine 50 mg and DVP 1000 mg per day for week 4; followed by DVP 1000 mg per day and discontinuation of quetiapine.

During a 4-week follow-up appointment, the patient reported appropriate completion of cross taper but stopped taking the DVP 3 days prior to the appointment due to self-reported lack of efficacy. For this reason, serum VPA level was not obtained. After discussion with his HCP, the patient restarted DVP 1000 mg per day without retitration with plans to get laboratory tests in 1 week. The next week, laboratory tests were notable for VPA level 28.74 (reference range, 50-100) µg/mL, low WBC 3.51 (reference range, 4.00-10.00) 10³/mcL, platelets 169 (reference range, 150-420) 10³/mcL, and low ANC 1.00 (reference range, 1.50-7.40) 10³/mcL (Table). This raised clinical concern as the patient had no history of documented neutropenia or leukopenia, with most recent complete blood count (CBC) prior to DVP initiation 3 months earlier while prescribed quetiapine.

Discussion

Our case report describes isolated neutropenia and leukopenia that developed after a cross taper from quetiapine to DVP. Hematologic abnormalities resolved after discontinuation of DVP, suggesting a likely correlation. DVP has a well-established, dose-related prevalence of thrombocytopenia occurring in up to 27% of patients.¹ Fewer case reports exist on neutropenia and leukopenia. DVP-induced neutropenia is thought to be a result of direct bone marrow suppression, whereas the more commonly occurring blood dyscrasia, thrombocytopenia, is thought to be caused by an antibody-mediated destruction of platelets.⁶

Management of DVP-induced thrombocytopenia is often dependent on the severity of the reaction. In mild-to-moderate cases, intervention may not be necessary as thrombocytopenia has been shown to resolve without adjustment to DVP therapy.¹ In more severe or symptomatic cases, dose reduction or discontinuation of the offending agent is recommended, typically resulting in resolution shortly following pharmacologic intervention.

Guidance on the management of other drug-induced hematologic abnormalities, such as neutropenia and leukopenia are not as well established. A 2019 systematic review of idiosyncratic drug-induced neutropenia suggested that continuing the offending drug with strict monitoring could be considered in cases of mild neutropenia. In cases of moderate neutropenia, the author suggests temporary cessation of the drug and reinstatement once neutrophil count normalizes and definitive cessation of the drug in severe cases.³⁰

In our case, continuing the offending agent with close monitoring was considered, similar to the well-established management of clozapine-induced neutropenia. However, due to the concern that the ANC was bordering moderate neutropenia in the absence of a therapeutic VPA level as well as a significant reduction in platelets, although not meeting criteria for thrombocytopenia, the decision was made to err on the side of caution and discontinue the most likely offending agent.

It is important to highlight that DVP was replacing quetiapine in the form of a cross taper. Quetiapine is structurally similar to clozapine. While clozapine has strict monitoring requirements related to neutropenia, blood dyscrasias with quetiapine therapy are rare. Quetiapine-induced hematologic abnormalities may be due to direct toxicity or to an immune-mediated mechanism, leading to bone marrow suppression.²⁰ Case reports documenting blood dyscrasias with the combination of DVP and quetiapine were identified during literature review.^15-19 Despite these case reports, we believe DVP was the primary offending agent in our case as the patient’s last dose of quetiapine was 2 weeks before obtaining the abnormal CBC. There was no history of blood dyscrasias with quetiapine monotherapy; however, the effect of the combination of DVP and quetiapine is unknown as no CBC was obtained during the cross-taper period.

Although there are no FDA-approved medications for the treatment of BPD, mood stabilizers, including DVP, have some research to support their use for the treatment of affective dysregulation and impulsive-behavioral dyscontrol.^26-28 In our case, DVP was selected due to the evidence for use in BPD and ability to assess adherence with therapeutic monitoring. Although polypharmacy is a concern in patients with BPD, in our case we believed that the patient’s ongoing mood lability and impulsive behaviors warranted pharmacologic intervention. Additionally, DVP provided an advantage in its ability to quickly titrate to therapeutic dose when compared with lamotrigine and a lower risk of cognitive AEs when compared with topiramate.

Conclusions

To our knowledge, this case report demonstrates the first published case of neutropenia and leukopenia related to DVP therapy for the treatment of BPD. Routine CBC monitoring is recommended with DVP therapy, and our case highlights the importance of evaluating for not only thrombocytopenia, but also other blood dyscrasias during the titration phase even in the absence of a therapeutic VPA level. Further studies are warranted to determine incidence of DVP-related neutropenia and leukopenia and to evaluate the safety of continuing DVP in cases of mild-to-moderate neutropenia with close monitoring.

Edema blisters are a common but often underreported entity most commonly seen on the lower extremities in the setting of acute edema. ¹ Reported risk factors and associations include chronic venous insufficiency, congestive heart failure, hereditary angioedema, and medications (eg, amlodipine). ^1,2 We report a newly described variant that we have termed anasarca-induced desquamation in which a patient sloughed the entire cutaneous surface of the body after gaining almost 40 pounds over 5 days.

Case Report

A 50-year-old man without a home was found minimally responsive in a yard. His core body temperature was 25.5 °C. He was profoundly acidotic (pH, <6.733 [reference range, 7.35–7.45]; lactic acid, 20.5 mmol/L [reference range, 0.5–2.2 mmol/L]) at admission. His medical history was notable for diabetes mellitus, hypertension, alcohol abuse, and pulmonary embolism. The patient was resuscitated with rewarming and intravenous fluids in the setting of acute renal insufficiency. By day 5 of the hospital stay, he had a net positive intake of 21.8 L and an 18-kg (39.7-lb) weight gain.

Dermatology was consulted for skin sloughing. Physical examination revealed nonpainful desquamation of the vermilion lip, periorbital skin, right shoulder, and hips without notable mucosal changes. Two 4-mm punch biopsies of the shoulder revealed an intracorneal split with desquamation of the stratum corneum and a mild dermal lymphocytic infiltrate, consistent with exfoliation secondary to edema or staphylococcal scalded skin syndrome (Figure 1). No staphylococcal growth was noted on blood, urine, nasal, wound, and ocular cultures throughout the hospital stay.

As the patient’s anasarca improved with diuretics and continuous renal replacement therapy, the entire cutaneous surface—head to toe—underwent desquamation, including the palms and soles. He was managed with supportive skin care. The anasarca healed completely with residual hypopigmentation (Figures 2 and 3).

Comment

Anasarca-induced desquamation represents a more diffuse form of a known entity: edema blisters. Occurring most commonly in the setting of acute exacerbation of chronic venous insufficiency, edema blisters can mimic other vesiculobullous conditions, such as bullous pemphigoid and herpes zoster.³

Pathogenesis of Edema Blisters—Edema develops in the skin when the capillary filtration rate, determined by the hydrostatic and oncotic pressures of the capillaries and interstitium, exceeds venous and lymphatic drainage. The appearance of edema blisters in the acute setting likely is related to the speed at which edema develops in skin.¹ Although edema blisters often are described as tense, there is a paucity of histologic data at the anatomical level of split in the skin.In our patient, desquamation was within the stratum corneum and likely multifactorial. His weight gain of nearly 40 lb, the result of intravenous instillation of fluids and low urine output, was undeniably a contributing factor. The anasarca was aggravated by hypoalbuminemia (2.1 g/dL) in the setting of known liver disease. Other possible contributing factors were hypotension, which required vasopressor therapy that led to hypoperfusion of the skin, and treatment of hypothermia, with resulting reactive vasodilation and capillary leak.

Management—Treatment of acute edema blisters is focused on the underlying cause of the edema. In a study of 13 patients with edema blisters, all had blisters on the legs that resolved with treatment, such as diuretics or compression therapy.¹

Anasarca-induced desquamation is an inherently benign condition that mimics potentially fatal disorders, such as Stevens-Johnson syndrome, staphylococcal scalded skin syndrome, and toxic shock syndrome. Therefore, patients presenting with diffuse superficial desquamation should be assessed for the mucosal changes of Stevens-Johnson syndrome and a history of acute edema in the affected areas to avoid potentially harmful empiric treatments, such as corticosteroids and intravenous antibiotics.

Conclusion

Anasarca-induced desquamation represents a more diffuse form of edema blisters. This desquamation can mimic a potentially fatal rash, such as Stevens-Johnson syndrome and staphylococcal scalded skin syndrome.

Edema blisters are a common but often underreported entity most commonly seen on the lower extremities in the setting of acute edema. ¹ Reported risk factors and associations include chronic venous insufficiency, congestive heart failure, hereditary angioedema, and medications (eg, amlodipine). ^1,2 We report a newly described variant that we have termed anasarca-induced desquamation in which a patient sloughed the entire cutaneous surface of the body after gaining almost 40 pounds over 5 days.

Case Report

A 50-year-old man without a home was found minimally responsive in a yard. His core body temperature was 25.5 °C. He was profoundly acidotic (pH, <6.733 [reference range, 7.35–7.45]; lactic acid, 20.5 mmol/L [reference range, 0.5–2.2 mmol/L]) at admission. His medical history was notable for diabetes mellitus, hypertension, alcohol abuse, and pulmonary embolism. The patient was resuscitated with rewarming and intravenous fluids in the setting of acute renal insufficiency. By day 5 of the hospital stay, he had a net positive intake of 21.8 L and an 18-kg (39.7-lb) weight gain.

Dermatology was consulted for skin sloughing. Physical examination revealed nonpainful desquamation of the vermilion lip, periorbital skin, right shoulder, and hips without notable mucosal changes. Two 4-mm punch biopsies of the shoulder revealed an intracorneal split with desquamation of the stratum corneum and a mild dermal lymphocytic infiltrate, consistent with exfoliation secondary to edema or staphylococcal scalded skin syndrome (Figure 1). No staphylococcal growth was noted on blood, urine, nasal, wound, and ocular cultures throughout the hospital stay.

As the patient’s anasarca improved with diuretics and continuous renal replacement therapy, the entire cutaneous surface—head to toe—underwent desquamation, including the palms and soles. He was managed with supportive skin care. The anasarca healed completely with residual hypopigmentation (Figures 2 and 3).

Comment

Anasarca-induced desquamation represents a more diffuse form of a known entity: edema blisters. Occurring most commonly in the setting of acute exacerbation of chronic venous insufficiency, edema blisters can mimic other vesiculobullous conditions, such as bullous pemphigoid and herpes zoster.³

Pathogenesis of Edema Blisters—Edema develops in the skin when the capillary filtration rate, determined by the hydrostatic and oncotic pressures of the capillaries and interstitium, exceeds venous and lymphatic drainage. The appearance of edema blisters in the acute setting likely is related to the speed at which edema develops in skin.¹ Although edema blisters often are described as tense, there is a paucity of histologic data at the anatomical level of split in the skin.In our patient, desquamation was within the stratum corneum and likely multifactorial. His weight gain of nearly 40 lb, the result of intravenous instillation of fluids and low urine output, was undeniably a contributing factor. The anasarca was aggravated by hypoalbuminemia (2.1 g/dL) in the setting of known liver disease. Other possible contributing factors were hypotension, which required vasopressor therapy that led to hypoperfusion of the skin, and treatment of hypothermia, with resulting reactive vasodilation and capillary leak.

Management—Treatment of acute edema blisters is focused on the underlying cause of the edema. In a study of 13 patients with edema blisters, all had blisters on the legs that resolved with treatment, such as diuretics or compression therapy.¹

Anasarca-induced desquamation is an inherently benign condition that mimics potentially fatal disorders, such as Stevens-Johnson syndrome, staphylococcal scalded skin syndrome, and toxic shock syndrome. Therefore, patients presenting with diffuse superficial desquamation should be assessed for the mucosal changes of Stevens-Johnson syndrome and a history of acute edema in the affected areas to avoid potentially harmful empiric treatments, such as corticosteroids and intravenous antibiotics.

Conclusion

Anasarca-induced desquamation represents a more diffuse form of edema blisters. This desquamation can mimic a potentially fatal rash, such as Stevens-Johnson syndrome and staphylococcal scalded skin syndrome.

Edema blisters are a common but often underreported entity most commonly seen on the lower extremities in the setting of acute edema. ¹ Reported risk factors and associations include chronic venous insufficiency, congestive heart failure, hereditary angioedema, and medications (eg, amlodipine). ^1,2 We report a newly described variant that we have termed anasarca-induced desquamation in which a patient sloughed the entire cutaneous surface of the body after gaining almost 40 pounds over 5 days.

Case Report

A 50-year-old man without a home was found minimally responsive in a yard. His core body temperature was 25.5 °C. He was profoundly acidotic (pH, <6.733 [reference range, 7.35–7.45]; lactic acid, 20.5 mmol/L [reference range, 0.5–2.2 mmol/L]) at admission. His medical history was notable for diabetes mellitus, hypertension, alcohol abuse, and pulmonary embolism. The patient was resuscitated with rewarming and intravenous fluids in the setting of acute renal insufficiency. By day 5 of the hospital stay, he had a net positive intake of 21.8 L and an 18-kg (39.7-lb) weight gain.

Dermatology was consulted for skin sloughing. Physical examination revealed nonpainful desquamation of the vermilion lip, periorbital skin, right shoulder, and hips without notable mucosal changes. Two 4-mm punch biopsies of the shoulder revealed an intracorneal split with desquamation of the stratum corneum and a mild dermal lymphocytic infiltrate, consistent with exfoliation secondary to edema or staphylococcal scalded skin syndrome (Figure 1). No staphylococcal growth was noted on blood, urine, nasal, wound, and ocular cultures throughout the hospital stay.

As the patient’s anasarca improved with diuretics and continuous renal replacement therapy, the entire cutaneous surface—head to toe—underwent desquamation, including the palms and soles. He was managed with supportive skin care. The anasarca healed completely with residual hypopigmentation (Figures 2 and 3).

Comment

Anasarca-induced desquamation represents a more diffuse form of a known entity: edema blisters. Occurring most commonly in the setting of acute exacerbation of chronic venous insufficiency, edema blisters can mimic other vesiculobullous conditions, such as bullous pemphigoid and herpes zoster.³

Pathogenesis of Edema Blisters—Edema develops in the skin when the capillary filtration rate, determined by the hydrostatic and oncotic pressures of the capillaries and interstitium, exceeds venous and lymphatic drainage. The appearance of edema blisters in the acute setting likely is related to the speed at which edema develops in skin.¹ Although edema blisters often are described as tense, there is a paucity of histologic data at the anatomical level of split in the skin.In our patient, desquamation was within the stratum corneum and likely multifactorial. His weight gain of nearly 40 lb, the result of intravenous instillation of fluids and low urine output, was undeniably a contributing factor. The anasarca was aggravated by hypoalbuminemia (2.1 g/dL) in the setting of known liver disease. Other possible contributing factors were hypotension, which required vasopressor therapy that led to hypoperfusion of the skin, and treatment of hypothermia, with resulting reactive vasodilation and capillary leak.

Management—Treatment of acute edema blisters is focused on the underlying cause of the edema. In a study of 13 patients with edema blisters, all had blisters on the legs that resolved with treatment, such as diuretics or compression therapy.¹

Anasarca-induced desquamation is an inherently benign condition that mimics potentially fatal disorders, such as Stevens-Johnson syndrome, staphylococcal scalded skin syndrome, and toxic shock syndrome. Therefore, patients presenting with diffuse superficial desquamation should be assessed for the mucosal changes of Stevens-Johnson syndrome and a history of acute edema in the affected areas to avoid potentially harmful empiric treatments, such as corticosteroids and intravenous antibiotics.

Conclusion

Anasarca-induced desquamation represents a more diffuse form of edema blisters. This desquamation can mimic a potentially fatal rash, such as Stevens-Johnson syndrome and staphylococcal scalded skin syndrome.

Following the attacks of September 11, 2001, heightened concerns over bioterrorism and the potential use of smallpox as a biological weapon made smallpox vaccination a critical component of military readiness. Therefore, the US Military resumed its smallpox vaccination program in 2002 using the first-generation smallpox vaccine (Dryvax, Wyeth Pharmaceuticals), a live vaccinia virus vaccine created in the late 19th century. This vaccine was developed by pooling vaccinia strains from the skin of infected cows¹ and had previously been used during the worldwide vaccination campaign in the 1970s. Dryvax was associated with various cardiac and cutaneous complications, from benign hypersensitivity reactions to life-threatening eczema vaccinatum and progressive vaccinia.

Due to concerns that the remaining supply of Dryvax was insufficient to vaccinate the US population in the case of a bioterrorism attack, investigators developed the second-generation smallpox vaccine (ACAM2000, Sanofi Pasteur Biologics Co) using advances in vaccine technology.² ACAM2000 is a plaque-purified isolate of vaccinia virus propagated in cell culture, thereby reducing contaminants and lot-to-lot variation.¹ Clinical trials demonstrated comparable immunogenicity and frequency of adverse events compared with Dryvax,² and ACAM2000 replaced Dryvax in 2008. However, these trials focused on serious adverse events, such as cardiac complications and postvaccinal encephalitis, with less specific characterization and description of cutaneous eruptions.³

Since 2008, there have been few reports of cutaneous adverse reactions following vaccination with ACAM2000. Beachkofsky et al⁴ described 7 cases of papulovesicular eruptions and 1 case of generalized vaccinia. Freeman and Lenz⁵ described 4 cases of papulovesicular eruptions, and there has been 1 case of progressive vaccinia reported in a soldier with newly diagnosed acute myelogenous leukemia.⁶ Kramer⁷ described a patient with multiple vesiculopustular lesions secondary to autoinoculation. The distinct pruritic acral papulovesicular eruptions following ACAM2000 vaccination have occurred in healthy military service members at different locations since the introduction of ACAM2000. We describe an additional case of this unique cutaneous eruption, followed by a review of previously described cutaneous adverse events associated with smallpox vaccination.

Case Report

A 21-year-old female soldier who was otherwise healthy presented to the dermatology clinic with a pruritic papular eruption involving the upper and lower extremities of 1 week’s duration. The lesions first appeared 8 days after she received the ACAM2000 vaccine. She received no other concurrent vaccines, had no history of atopic dermatitis, and had no systemic symptoms. Physical examination revealed numerous erythematous indurated papules involving the dorsolateral hands and fingers, as well as the extensor surfaces of the elbows, knees, and thighs (Figures 1 and 2). Based on the clinical presentation, the differential diagnosis included lichen planus, verruca plana, dyshidrotic eczema, and smallpox vaccine reaction. Erythema multiforme was considered; however, the absence of palmoplantar involvement and typical targetoid lesions made this diagnosis less likely.

Biopsies of lesions on the arm and thigh were performed. Histologic findings revealed interface and spongiotic dermatitis with scattered necrotic keratinocytes and extravasated erythrocytes (Figure 3). There was no evidence of viral cytopathic effects. Similar clinical and histologic findings have been reported in the literature as acral papulovesicular eruptions following smallpox vaccination or papular spongiotic dermatitis of smallpox vaccination.⁸ The presence of eosinophils was not conspicuous in the current case and was only a notable finding in 1 of 2 cases previously described by Gaertner et al.⁸ This may simply be due to an idiosyncratic drug reaction. Furthermore, in the cases described by Beachkofsky et al,⁴ there were essentially 2 histologic groups. The first group demonstrated a dermal hypersensitivity-type reaction, and the second group demonstrated a lymphocytic capillaritis.

Based on these findings, the patient was diagnosed with an acral papulovesicular eruption following smallpox vaccination. Of note, the patient’s presentation was not consistent with other described smallpox vaccine reactions, which included eczema vaccinatum, autoinoculation, generalized vaccinia, and progressive vaccinia. The patient was treated supportively with triamcinolone acetonide cream 0.1%, cool compresses, and oral diphenhydramine as needed for pruritus. The lesions notably improved within the first week of treatment.

Comment

Reported cases of acral papulovesicular eruption^4-6 demonstrated an onset of cutaneous symptoms an average of 14 days following vaccination (range, 8–18 days postvaccination). Lesions were benign and self-limited in all cases, with resolution within an average of 25 days (range, 7–71 days). All patients were active-duty military adults with a mean age of 24 years. Supportive treatment varied from topical steroids and oral antihistamines to tapering oral prednisone doses. Of note, all previously reported cases of this reaction occurred in patients who also had received other concurrent or near-concurrent vaccines, including anthrax, hepatitis B, influenza, and typhoid. Our patient represents a unique case of a papulovesicular eruption following smallpox vaccination with no history of concurrent vaccines.

Since the 1970s, smallpox vaccination has been associated with numerous cutaneous reactions, most of which have been reported with the first-generation Dryvax. Minor local reactions occurred in approximately 2% to 6% of vaccinees in clinical trials.⁹ These reactions included local edema involving the upper arm, satellite lesions within 2.5 cm of the vaccination site, local lymphadenopathy, intense inflammation or viral cellulitis surrounding the inoculation site, and viral lymphangitis tracking to axillary lymph nodes. In clinical trials, these reactions were self-limited and required only symptomatic treatment.⁹

Autoinoculation is another cutaneous reaction that can occur because Dryvax and ACAM2000 both contain live-attenuated replicating vaccinia virus. Accidental implantation may occur when the high titers of virus present at the vaccine site are subsequently transferred to other sites, especially abnormal mucosa or skin, resulting in an additional primary inoculation site.¹⁰

Eczema vaccinatum is a potentially life-threatening reaction that may occur in patients with disruptive skin disorders, such as atopic dermatitis. These patients are at risk for massive confluent vaccinia infection of the skin.¹⁰ In patients with atopic dermatitis, the virus rapidly disseminates due to both skin barrier dysfunction and impaired immunomodulation, resulting in large confluent skin lesions and the potential for viremia, septic shock, and death.^10,11 Mortality from eczema vaccinatum may be reduced by administration of vaccinia immune globulin.¹⁰

The vaccinia virus also may spread hematogenously in healthy individuals,¹⁰ resulting in a benign reaction called generalized vaccinia. These patients develop pustules on areas of the skin other than the vaccination site. Although typically benign and self-limited, Beachkofsky et al⁴ described a case of generalized vaccinia in a healthy 34-year-old man resulting in a rapidly progressive vesiculopustular eruption with associated fever and pancytopenia. The patient made a complete recovery over the course of the following month.⁴

Alternatively, progressive vaccinia is a severe complication of smallpox vaccination seen in patients with impaired cell-mediated immunity. It also is known as vaccinia gangrenosum or vaccinia necrosum. These patients develop expanding ulcers due to exaggerated viral replication and cell-to-cell spread of the vaccinia virus.^10,11 Hematogenous spread may result in viral implantation at distant sites of the body. This disease slowly progresses over weeks to months, and it often is resistant to treatment and fatal in patients with severe T-cell deficiency.¹⁰

Acral papulovesicular eruption is a distinct cutaneous adverse event following smallpox vaccination. Although further research is needed to discern the pathogenesis of this reaction, it is benign and self-limited, and patients have fully recovered with supportive care. In addition, a modified vaccinia Ankara vaccine (Bavarian Nordic) was approved by the US Food and Drug Administration in 2019.^12,13 It is a nonreplicating attenuated viral vaccine that had fewer adverse events compared to ACAM2000 in clinical trials.¹³ To date, papulovesicular eruptions have not been reported following vaccination with the modified vaccinia Ankara vaccine; however, continued monitoring will help to further characterize any cutaneous reactions to this newer vaccine.

Following the attacks of September 11, 2001, heightened concerns over bioterrorism and the potential use of smallpox as a biological weapon made smallpox vaccination a critical component of military readiness. Therefore, the US Military resumed its smallpox vaccination program in 2002 using the first-generation smallpox vaccine (Dryvax, Wyeth Pharmaceuticals), a live vaccinia virus vaccine created in the late 19th century. This vaccine was developed by pooling vaccinia strains from the skin of infected cows¹ and had previously been used during the worldwide vaccination campaign in the 1970s. Dryvax was associated with various cardiac and cutaneous complications, from benign hypersensitivity reactions to life-threatening eczema vaccinatum and progressive vaccinia.

Due to concerns that the remaining supply of Dryvax was insufficient to vaccinate the US population in the case of a bioterrorism attack, investigators developed the second-generation smallpox vaccine (ACAM2000, Sanofi Pasteur Biologics Co) using advances in vaccine technology.² ACAM2000 is a plaque-purified isolate of vaccinia virus propagated in cell culture, thereby reducing contaminants and lot-to-lot variation.¹ Clinical trials demonstrated comparable immunogenicity and frequency of adverse events compared with Dryvax,² and ACAM2000 replaced Dryvax in 2008. However, these trials focused on serious adverse events, such as cardiac complications and postvaccinal encephalitis, with less specific characterization and description of cutaneous eruptions.³

Since 2008, there have been few reports of cutaneous adverse reactions following vaccination with ACAM2000. Beachkofsky et al⁴ described 7 cases of papulovesicular eruptions and 1 case of generalized vaccinia. Freeman and Lenz⁵ described 4 cases of papulovesicular eruptions, and there has been 1 case of progressive vaccinia reported in a soldier with newly diagnosed acute myelogenous leukemia.⁶ Kramer⁷ described a patient with multiple vesiculopustular lesions secondary to autoinoculation. The distinct pruritic acral papulovesicular eruptions following ACAM2000 vaccination have occurred in healthy military service members at different locations since the introduction of ACAM2000. We describe an additional case of this unique cutaneous eruption, followed by a review of previously described cutaneous adverse events associated with smallpox vaccination.

Case Report

A 21-year-old female soldier who was otherwise healthy presented to the dermatology clinic with a pruritic papular eruption involving the upper and lower extremities of 1 week’s duration. The lesions first appeared 8 days after she received the ACAM2000 vaccine. She received no other concurrent vaccines, had no history of atopic dermatitis, and had no systemic symptoms. Physical examination revealed numerous erythematous indurated papules involving the dorsolateral hands and fingers, as well as the extensor surfaces of the elbows, knees, and thighs (Figures 1 and 2). Based on the clinical presentation, the differential diagnosis included lichen planus, verruca plana, dyshidrotic eczema, and smallpox vaccine reaction. Erythema multiforme was considered; however, the absence of palmoplantar involvement and typical targetoid lesions made this diagnosis less likely.

Biopsies of lesions on the arm and thigh were performed. Histologic findings revealed interface and spongiotic dermatitis with scattered necrotic keratinocytes and extravasated erythrocytes (Figure 3). There was no evidence of viral cytopathic effects. Similar clinical and histologic findings have been reported in the literature as acral papulovesicular eruptions following smallpox vaccination or papular spongiotic dermatitis of smallpox vaccination.⁸ The presence of eosinophils was not conspicuous in the current case and was only a notable finding in 1 of 2 cases previously described by Gaertner et al.⁸ This may simply be due to an idiosyncratic drug reaction. Furthermore, in the cases described by Beachkofsky et al,⁴ there were essentially 2 histologic groups. The first group demonstrated a dermal hypersensitivity-type reaction, and the second group demonstrated a lymphocytic capillaritis.

Based on these findings, the patient was diagnosed with an acral papulovesicular eruption following smallpox vaccination. Of note, the patient’s presentation was not consistent with other described smallpox vaccine reactions, which included eczema vaccinatum, autoinoculation, generalized vaccinia, and progressive vaccinia. The patient was treated supportively with triamcinolone acetonide cream 0.1%, cool compresses, and oral diphenhydramine as needed for pruritus. The lesions notably improved within the first week of treatment.

Comment

Reported cases of acral papulovesicular eruption^4-6 demonstrated an onset of cutaneous symptoms an average of 14 days following vaccination (range, 8–18 days postvaccination). Lesions were benign and self-limited in all cases, with resolution within an average of 25 days (range, 7–71 days). All patients were active-duty military adults with a mean age of 24 years. Supportive treatment varied from topical steroids and oral antihistamines to tapering oral prednisone doses. Of note, all previously reported cases of this reaction occurred in patients who also had received other concurrent or near-concurrent vaccines, including anthrax, hepatitis B, influenza, and typhoid. Our patient represents a unique case of a papulovesicular eruption following smallpox vaccination with no history of concurrent vaccines.

Since the 1970s, smallpox vaccination has been associated with numerous cutaneous reactions, most of which have been reported with the first-generation Dryvax. Minor local reactions occurred in approximately 2% to 6% of vaccinees in clinical trials.⁹ These reactions included local edema involving the upper arm, satellite lesions within 2.5 cm of the vaccination site, local lymphadenopathy, intense inflammation or viral cellulitis surrounding the inoculation site, and viral lymphangitis tracking to axillary lymph nodes. In clinical trials, these reactions were self-limited and required only symptomatic treatment.⁹

Autoinoculation is another cutaneous reaction that can occur because Dryvax and ACAM2000 both contain live-attenuated replicating vaccinia virus. Accidental implantation may occur when the high titers of virus present at the vaccine site are subsequently transferred to other sites, especially abnormal mucosa or skin, resulting in an additional primary inoculation site.¹⁰

Eczema vaccinatum is a potentially life-threatening reaction that may occur in patients with disruptive skin disorders, such as atopic dermatitis. These patients are at risk for massive confluent vaccinia infection of the skin.¹⁰ In patients with atopic dermatitis, the virus rapidly disseminates due to both skin barrier dysfunction and impaired immunomodulation, resulting in large confluent skin lesions and the potential for viremia, septic shock, and death.^10,11 Mortality from eczema vaccinatum may be reduced by administration of vaccinia immune globulin.¹⁰

The vaccinia virus also may spread hematogenously in healthy individuals,¹⁰ resulting in a benign reaction called generalized vaccinia. These patients develop pustules on areas of the skin other than the vaccination site. Although typically benign and self-limited, Beachkofsky et al⁴ described a case of generalized vaccinia in a healthy 34-year-old man resulting in a rapidly progressive vesiculopustular eruption with associated fever and pancytopenia. The patient made a complete recovery over the course of the following month.⁴

Alternatively, progressive vaccinia is a severe complication of smallpox vaccination seen in patients with impaired cell-mediated immunity. It also is known as vaccinia gangrenosum or vaccinia necrosum. These patients develop expanding ulcers due to exaggerated viral replication and cell-to-cell spread of the vaccinia virus.^10,11 Hematogenous spread may result in viral implantation at distant sites of the body. This disease slowly progresses over weeks to months, and it often is resistant to treatment and fatal in patients with severe T-cell deficiency.¹⁰

Acral papulovesicular eruption is a distinct cutaneous adverse event following smallpox vaccination. Although further research is needed to discern the pathogenesis of this reaction, it is benign and self-limited, and patients have fully recovered with supportive care. In addition, a modified vaccinia Ankara vaccine (Bavarian Nordic) was approved by the US Food and Drug Administration in 2019.^12,13 It is a nonreplicating attenuated viral vaccine that had fewer adverse events compared to ACAM2000 in clinical trials.¹³ To date, papulovesicular eruptions have not been reported following vaccination with the modified vaccinia Ankara vaccine; however, continued monitoring will help to further characterize any cutaneous reactions to this newer vaccine.

Following the attacks of September 11, 2001, heightened concerns over bioterrorism and the potential use of smallpox as a biological weapon made smallpox vaccination a critical component of military readiness. Therefore, the US Military resumed its smallpox vaccination program in 2002 using the first-generation smallpox vaccine (Dryvax, Wyeth Pharmaceuticals), a live vaccinia virus vaccine created in the late 19th century. This vaccine was developed by pooling vaccinia strains from the skin of infected cows¹ and had previously been used during the worldwide vaccination campaign in the 1970s. Dryvax was associated with various cardiac and cutaneous complications, from benign hypersensitivity reactions to life-threatening eczema vaccinatum and progressive vaccinia.

Due to concerns that the remaining supply of Dryvax was insufficient to vaccinate the US population in the case of a bioterrorism attack, investigators developed the second-generation smallpox vaccine (ACAM2000, Sanofi Pasteur Biologics Co) using advances in vaccine technology.² ACAM2000 is a plaque-purified isolate of vaccinia virus propagated in cell culture, thereby reducing contaminants and lot-to-lot variation.¹ Clinical trials demonstrated comparable immunogenicity and frequency of adverse events compared with Dryvax,² and ACAM2000 replaced Dryvax in 2008. However, these trials focused on serious adverse events, such as cardiac complications and postvaccinal encephalitis, with less specific characterization and description of cutaneous eruptions.³

Since 2008, there have been few reports of cutaneous adverse reactions following vaccination with ACAM2000. Beachkofsky et al⁴ described 7 cases of papulovesicular eruptions and 1 case of generalized vaccinia. Freeman and Lenz⁵ described 4 cases of papulovesicular eruptions, and there has been 1 case of progressive vaccinia reported in a soldier with newly diagnosed acute myelogenous leukemia.⁶ Kramer⁷ described a patient with multiple vesiculopustular lesions secondary to autoinoculation. The distinct pruritic acral papulovesicular eruptions following ACAM2000 vaccination have occurred in healthy military service members at different locations since the introduction of ACAM2000. We describe an additional case of this unique cutaneous eruption, followed by a review of previously described cutaneous adverse events associated with smallpox vaccination.

Case Report

A 21-year-old female soldier who was otherwise healthy presented to the dermatology clinic with a pruritic papular eruption involving the upper and lower extremities of 1 week’s duration. The lesions first appeared 8 days after she received the ACAM2000 vaccine. She received no other concurrent vaccines, had no history of atopic dermatitis, and had no systemic symptoms. Physical examination revealed numerous erythematous indurated papules involving the dorsolateral hands and fingers, as well as the extensor surfaces of the elbows, knees, and thighs (Figures 1 and 2). Based on the clinical presentation, the differential diagnosis included lichen planus, verruca plana, dyshidrotic eczema, and smallpox vaccine reaction. Erythema multiforme was considered; however, the absence of palmoplantar involvement and typical targetoid lesions made this diagnosis less likely.

Biopsies of lesions on the arm and thigh were performed. Histologic findings revealed interface and spongiotic dermatitis with scattered necrotic keratinocytes and extravasated erythrocytes (Figure 3). There was no evidence of viral cytopathic effects. Similar clinical and histologic findings have been reported in the literature as acral papulovesicular eruptions following smallpox vaccination or papular spongiotic dermatitis of smallpox vaccination.⁸ The presence of eosinophils was not conspicuous in the current case and was only a notable finding in 1 of 2 cases previously described by Gaertner et al.⁸ This may simply be due to an idiosyncratic drug reaction. Furthermore, in the cases described by Beachkofsky et al,⁴ there were essentially 2 histologic groups. The first group demonstrated a dermal hypersensitivity-type reaction, and the second group demonstrated a lymphocytic capillaritis.

Based on these findings, the patient was diagnosed with an acral papulovesicular eruption following smallpox vaccination. Of note, the patient’s presentation was not consistent with other described smallpox vaccine reactions, which included eczema vaccinatum, autoinoculation, generalized vaccinia, and progressive vaccinia. The patient was treated supportively with triamcinolone acetonide cream 0.1%, cool compresses, and oral diphenhydramine as needed for pruritus. The lesions notably improved within the first week of treatment.

Comment

Reported cases of acral papulovesicular eruption^4-6 demonstrated an onset of cutaneous symptoms an average of 14 days following vaccination (range, 8–18 days postvaccination). Lesions were benign and self-limited in all cases, with resolution within an average of 25 days (range, 7–71 days). All patients were active-duty military adults with a mean age of 24 years. Supportive treatment varied from topical steroids and oral antihistamines to tapering oral prednisone doses. Of note, all previously reported cases of this reaction occurred in patients who also had received other concurrent or near-concurrent vaccines, including anthrax, hepatitis B, influenza, and typhoid. Our patient represents a unique case of a papulovesicular eruption following smallpox vaccination with no history of concurrent vaccines.

Since the 1970s, smallpox vaccination has been associated with numerous cutaneous reactions, most of which have been reported with the first-generation Dryvax. Minor local reactions occurred in approximately 2% to 6% of vaccinees in clinical trials.⁹ These reactions included local edema involving the upper arm, satellite lesions within 2.5 cm of the vaccination site, local lymphadenopathy, intense inflammation or viral cellulitis surrounding the inoculation site, and viral lymphangitis tracking to axillary lymph nodes. In clinical trials, these reactions were self-limited and required only symptomatic treatment.⁹

Autoinoculation is another cutaneous reaction that can occur because Dryvax and ACAM2000 both contain live-attenuated replicating vaccinia virus. Accidental implantation may occur when the high titers of virus present at the vaccine site are subsequently transferred to other sites, especially abnormal mucosa or skin, resulting in an additional primary inoculation site.¹⁰

Eczema vaccinatum is a potentially life-threatening reaction that may occur in patients with disruptive skin disorders, such as atopic dermatitis. These patients are at risk for massive confluent vaccinia infection of the skin.¹⁰ In patients with atopic dermatitis, the virus rapidly disseminates due to both skin barrier dysfunction and impaired immunomodulation, resulting in large confluent skin lesions and the potential for viremia, septic shock, and death.^10,11 Mortality from eczema vaccinatum may be reduced by administration of vaccinia immune globulin.¹⁰

The vaccinia virus also may spread hematogenously in healthy individuals,¹⁰ resulting in a benign reaction called generalized vaccinia. These patients develop pustules on areas of the skin other than the vaccination site. Although typically benign and self-limited, Beachkofsky et al⁴ described a case of generalized vaccinia in a healthy 34-year-old man resulting in a rapidly progressive vesiculopustular eruption with associated fever and pancytopenia. The patient made a complete recovery over the course of the following month.⁴

Alternatively, progressive vaccinia is a severe complication of smallpox vaccination seen in patients with impaired cell-mediated immunity. It also is known as vaccinia gangrenosum or vaccinia necrosum. These patients develop expanding ulcers due to exaggerated viral replication and cell-to-cell spread of the vaccinia virus.^10,11 Hematogenous spread may result in viral implantation at distant sites of the body. This disease slowly progresses over weeks to months, and it often is resistant to treatment and fatal in patients with severe T-cell deficiency.¹⁰

Acral papulovesicular eruption is a distinct cutaneous adverse event following smallpox vaccination. Although further research is needed to discern the pathogenesis of this reaction, it is benign and self-limited, and patients have fully recovered with supportive care. In addition, a modified vaccinia Ankara vaccine (Bavarian Nordic) was approved by the US Food and Drug Administration in 2019.^12,13 It is a nonreplicating attenuated viral vaccine that had fewer adverse events compared to ACAM2000 in clinical trials.¹³ To date, papulovesicular eruptions have not been reported following vaccination with the modified vaccinia Ankara vaccine; however, continued monitoring will help to further characterize any cutaneous reactions to this newer vaccine.

Case Report

A 58-year-old woman presented to the dermatology office with a widespread pruritic eruption of 3 days’ duration that started in the groin and spread to the rest of the body. No treatments had been attempted. She had no notable medical history, and she denied any recent illness, change in personal care products, or new medications or supplements. She reported a camping trip 2 weeks prior to presentation on the east end of Long Island, New York. She later learned that others on the same trip developed a similar, albeit less widespread, eruption.

Physical examination revealed clear vesicles on the arms, legs, trunk, and pubic area (Figure 1). Dermoscopy revealed a small lone star tick larva in the center of one of the vesicles (Figure 2). The type of tick larva was identified using resources from the Centers for Disease Control and Prevention (Figure 3).¹ Careful inspection revealed dark marks on various vesicles, mostly in the perineum, yielding nearly 20 larvae, which were removed with forceps. The patient was counseled to cover herself in petrolatum for 2 to 3 hours with the hope of smothering any remaining tick larvae. She was given triamcinolone cream and was encouraged to take a nonsedating antihistamine for itch. The patient was seen back in clinic 2 weeks later and the eruption had resolved.

Comment

Spread of Tick-Borne Disease—Ticks and tick-borne disease are increasing major health concerns for humans, domesticated animals, and livestock. Reported cases of bacterial and protozoan tick-borne disease doubled in the United States between 2004 and 2016. Ninety percent of the nearly 60,000 cases of nationally notifiable vector-borne diseases reported in 2017 were linked to ticks.² Geographic ranges of multiple tick species continue to expand, which is thought to be secondary to rising global temperatures, ecologic changes, reforestation, and increases in commerce and travel (Figure 4).³ Not only have warming temperatures contributed to geographic range expansion, they also may extend ticks’ active season. The lone star tick (Amblyomma americanum) is widely distributed throughout much of the eastern United States.⁴ The range of A americanum has expanded north in recent years from its prior core range in the southeastern United States.² One study found that from 2006 to 2016, the vector tick species most commonly collected from humans and submitted to a tick surveillance system in New Jersey shifted from Ixodes scapularis to A americanum.⁵

Bites by Amblyomma Ticks—As with most hard ticks, the life cycle of A americanum lasts 2 years and includes the egg, the 6-legged larva or “seed tick,” the 8-legged immature nymph, and the 8-legged reproductively mature adult (Figure 3). Amblyomma americanum can lay several thousand eggs.² Because our patient had numerous bites, it is plausible that she came into contact with a nest of newly hatched tick larvae. Morphogenesis from larva to nymph, then nymph to adult, requires a blood meal.^6,7 The larvae emerge from eggs deposited on the ground and then crawl up low vegetation where they can easily attach to passing hosts. The tick clings to hair or clothing and waits until the host is at rest before moving to a favorable location and then bites.⁸ When attaching, ticks inject an anesthetic akin to lidocaine, making the bite painless. A tick may spend up to 24 hours on the host prior to biting and then feed for 2 hours to 7 days before releasing.⁹ For the majority of tick-borne illnesses, the tick must remain attached for 24 to 48 hours before disease is transmitted.¹⁰

All stages of Amblyomma, excluding the egg, are capable of transmitting disease.^8,11Amblyomma americanum is called the lone star tick because of the prominent white dot on the back of the adult female. It will feed on small or large mammals during any stage of its life cycle. It is known to transmit Ehrlichia chaffeensis and Ehrlichia ewingii, which cause human ehrlichiosis, and Francisella tularensis, which causes tularemia, Heartland virus, Bourbon virus, and Southern tick-associated rash illness. Delayed anaphylaxis to ingestion of red meat has been attributed to the bite of A americanum. Amblyomma americanum ticks are not known to transmit Lyme disease. The Centers for Disease Control and Prevention does not recommend prophylactic treatment to prevent ehrlichiosis.¹² Tularemia prophylaxis is only recommended in cases of laboratory exposure to infectious materials. Doxycycline prophylaxis is only recommended if the tick is identified as an adult or nymphal I scapularis.¹²

Even when the ticks do not transmit disease, tick bites can cause impressive local reactions. Uncomplicated bites can be painful and leave a puncture wound that can take 1 to 2 weeks to heal.¹³ Rarely, bites can cause a delayed hypersensitivity reaction including fever, pruritus, and urticaria. Granulomas can develop if a tick is improperly removed.⁹ Other reports describe prurigo lesions, skin hemorrhage, papular urticaria, diffuse papules, vesicles and bullae, necrotic ulcers, and patchy alopecia.^14,15 A 2015 systematic controlled study of human bite reactions from A americanum demonstrated the development of itchy erythematous papules and vesicles within 48 hours of larval tick attachment to research participants. The study found tissue damage from A americanum mouthparts, and degranulating mast cells may be evident in as little as 15 minutes.¹⁶ The severity of individual skin reaction is hypothesized to depend on several variables, such as the duration of feeding, size of mouthparts, type of tick secretions, changes in secretions during feeding, and prior exposures of the host.¹⁴

Tick Removal—If patients present to clinic with ticks attached, removal can be challenging. Removal recommendations call for use of blunt forceps or tweezers. Ticks should be grasped near the skin with consistent pressure, and the tick should be pulled straight out, perpendicular to the skin. Twisting motions can cause the head to separate from the body and remain in the bite wound. Immediately following removal, the area should be cleansed with a disinfectant.^10,17 After the tick is removed, some studies recommend storing the tick at −20 °C; should the patient develop disease, the tick could be sent for evaluation.^6,17 If there is no clinical or serologic evidence of infection, testing for the presence of antibodies against tick-borne bacteria at presentation and at 3 and 6 weeks is not recommended due to low sensitivity, low positive predictive value, and cost. Clinicians must only observe and treat if disease occurs.¹⁷

Prevention of Tick Bites—Tick bites are best prevented by avoiding tick-infested areas; when these areas are unavoidable, tick bites may be prevented by wearing long pants with the pant legs tucked into boots. In addition, applying topical DEET (N,N-diethyl-m-toluamide) repellent to exposed skin and treating clothing with permethrin can be helpful.¹⁷ When used alone, DEET provides greater than 90% protection for up to 2.7 hours against A americanum.¹⁸ Permethrin-treated clothing alone is 79% to 100% effective at killing A americanum ticks or disabling them for several hours.¹⁹

Conclusion

Tick-borne illness is an increasingly important cause of human infectious disease. In addition to their role as a disease vector, ticks can produce primary skin disorders. This case posed a diagnostic challenge because of the unusually large number and wide distribution of bites as well as the subsequent vesicular reaction that ensued. It is important to keep tick larvae or adult tick bites in the differential when evaluating a patient to expedite tick removal and begin clinical monitoring. Recognition of A americanum larvae as a potential cause of pruritic papules may be helpful in similar cases. In addition, it is important for dermatologists to be aware of the tick species in their area.

Case Report

A 58-year-old woman presented to the dermatology office with a widespread pruritic eruption of 3 days’ duration that started in the groin and spread to the rest of the body. No treatments had been attempted. She had no notable medical history, and she denied any recent illness, change in personal care products, or new medications or supplements. She reported a camping trip 2 weeks prior to presentation on the east end of Long Island, New York. She later learned that others on the same trip developed a similar, albeit less widespread, eruption.

Physical examination revealed clear vesicles on the arms, legs, trunk, and pubic area (Figure 1). Dermoscopy revealed a small lone star tick larva in the center of one of the vesicles (Figure 2). The type of tick larva was identified using resources from the Centers for Disease Control and Prevention (Figure 3).¹ Careful inspection revealed dark marks on various vesicles, mostly in the perineum, yielding nearly 20 larvae, which were removed with forceps. The patient was counseled to cover herself in petrolatum for 2 to 3 hours with the hope of smothering any remaining tick larvae. She was given triamcinolone cream and was encouraged to take a nonsedating antihistamine for itch. The patient was seen back in clinic 2 weeks later and the eruption had resolved.

Comment

Spread of Tick-Borne Disease—Ticks and tick-borne disease are increasing major health concerns for humans, domesticated animals, and livestock. Reported cases of bacterial and protozoan tick-borne disease doubled in the United States between 2004 and 2016. Ninety percent of the nearly 60,000 cases of nationally notifiable vector-borne diseases reported in 2017 were linked to ticks.² Geographic ranges of multiple tick species continue to expand, which is thought to be secondary to rising global temperatures, ecologic changes, reforestation, and increases in commerce and travel (Figure 4).³ Not only have warming temperatures contributed to geographic range expansion, they also may extend ticks’ active season. The lone star tick (Amblyomma americanum) is widely distributed throughout much of the eastern United States.⁴ The range of A americanum has expanded north in recent years from its prior core range in the southeastern United States.² One study found that from 2006 to 2016, the vector tick species most commonly collected from humans and submitted to a tick surveillance system in New Jersey shifted from Ixodes scapularis to A americanum.⁵

Bites by Amblyomma Ticks—As with most hard ticks, the life cycle of A americanum lasts 2 years and includes the egg, the 6-legged larva or “seed tick,” the 8-legged immature nymph, and the 8-legged reproductively mature adult (Figure 3). Amblyomma americanum can lay several thousand eggs.² Because our patient had numerous bites, it is plausible that she came into contact with a nest of newly hatched tick larvae. Morphogenesis from larva to nymph, then nymph to adult, requires a blood meal.^6,7 The larvae emerge from eggs deposited on the ground and then crawl up low vegetation where they can easily attach to passing hosts. The tick clings to hair or clothing and waits until the host is at rest before moving to a favorable location and then bites.⁸ When attaching, ticks inject an anesthetic akin to lidocaine, making the bite painless. A tick may spend up to 24 hours on the host prior to biting and then feed for 2 hours to 7 days before releasing.⁹ For the majority of tick-borne illnesses, the tick must remain attached for 24 to 48 hours before disease is transmitted.¹⁰

All stages of Amblyomma, excluding the egg, are capable of transmitting disease.^8,11Amblyomma americanum is called the lone star tick because of the prominent white dot on the back of the adult female. It will feed on small or large mammals during any stage of its life cycle. It is known to transmit Ehrlichia chaffeensis and Ehrlichia ewingii, which cause human ehrlichiosis, and Francisella tularensis, which causes tularemia, Heartland virus, Bourbon virus, and Southern tick-associated rash illness. Delayed anaphylaxis to ingestion of red meat has been attributed to the bite of A americanum. Amblyomma americanum ticks are not known to transmit Lyme disease. The Centers for Disease Control and Prevention does not recommend prophylactic treatment to prevent ehrlichiosis.¹² Tularemia prophylaxis is only recommended in cases of laboratory exposure to infectious materials. Doxycycline prophylaxis is only recommended if the tick is identified as an adult or nymphal I scapularis.¹²

Even when the ticks do not transmit disease, tick bites can cause impressive local reactions. Uncomplicated bites can be painful and leave a puncture wound that can take 1 to 2 weeks to heal.¹³ Rarely, bites can cause a delayed hypersensitivity reaction including fever, pruritus, and urticaria. Granulomas can develop if a tick is improperly removed.⁹ Other reports describe prurigo lesions, skin hemorrhage, papular urticaria, diffuse papules, vesicles and bullae, necrotic ulcers, and patchy alopecia.^14,15 A 2015 systematic controlled study of human bite reactions from A americanum demonstrated the development of itchy erythematous papules and vesicles within 48 hours of larval tick attachment to research participants. The study found tissue damage from A americanum mouthparts, and degranulating mast cells may be evident in as little as 15 minutes.¹⁶ The severity of individual skin reaction is hypothesized to depend on several variables, such as the duration of feeding, size of mouthparts, type of tick secretions, changes in secretions during feeding, and prior exposures of the host.¹⁴

Tick Removal—If patients present to clinic with ticks attached, removal can be challenging. Removal recommendations call for use of blunt forceps or tweezers. Ticks should be grasped near the skin with consistent pressure, and the tick should be pulled straight out, perpendicular to the skin. Twisting motions can cause the head to separate from the body and remain in the bite wound. Immediately following removal, the area should be cleansed with a disinfectant.^10,17 After the tick is removed, some studies recommend storing the tick at −20 °C; should the patient develop disease, the tick could be sent for evaluation.^6,17 If there is no clinical or serologic evidence of infection, testing for the presence of antibodies against tick-borne bacteria at presentation and at 3 and 6 weeks is not recommended due to low sensitivity, low positive predictive value, and cost. Clinicians must only observe and treat if disease occurs.¹⁷

Prevention of Tick Bites—Tick bites are best prevented by avoiding tick-infested areas; when these areas are unavoidable, tick bites may be prevented by wearing long pants with the pant legs tucked into boots. In addition, applying topical DEET (N,N-diethyl-m-toluamide) repellent to exposed skin and treating clothing with permethrin can be helpful.¹⁷ When used alone, DEET provides greater than 90% protection for up to 2.7 hours against A americanum.¹⁸ Permethrin-treated clothing alone is 79% to 100% effective at killing A americanum ticks or disabling them for several hours.¹⁹

Conclusion

Tick-borne illness is an increasingly important cause of human infectious disease. In addition to their role as a disease vector, ticks can produce primary skin disorders. This case posed a diagnostic challenge because of the unusually large number and wide distribution of bites as well as the subsequent vesicular reaction that ensued. It is important to keep tick larvae or adult tick bites in the differential when evaluating a patient to expedite tick removal and begin clinical monitoring. Recognition of A americanum larvae as a potential cause of pruritic papules may be helpful in similar cases. In addition, it is important for dermatologists to be aware of the tick species in their area.

Case Report

A 58-year-old woman presented to the dermatology office with a widespread pruritic eruption of 3 days’ duration that started in the groin and spread to the rest of the body. No treatments had been attempted. She had no notable medical history, and she denied any recent illness, change in personal care products, or new medications or supplements. She reported a camping trip 2 weeks prior to presentation on the east end of Long Island, New York. She later learned that others on the same trip developed a similar, albeit less widespread, eruption.

Physical examination revealed clear vesicles on the arms, legs, trunk, and pubic area (Figure 1). Dermoscopy revealed a small lone star tick larva in the center of one of the vesicles (Figure 2). The type of tick larva was identified using resources from the Centers for Disease Control and Prevention (Figure 3).¹ Careful inspection revealed dark marks on various vesicles, mostly in the perineum, yielding nearly 20 larvae, which were removed with forceps. The patient was counseled to cover herself in petrolatum for 2 to 3 hours with the hope of smothering any remaining tick larvae. She was given triamcinolone cream and was encouraged to take a nonsedating antihistamine for itch. The patient was seen back in clinic 2 weeks later and the eruption had resolved.

Comment

Spread of Tick-Borne Disease—Ticks and tick-borne disease are increasing major health concerns for humans, domesticated animals, and livestock. Reported cases of bacterial and protozoan tick-borne disease doubled in the United States between 2004 and 2016. Ninety percent of the nearly 60,000 cases of nationally notifiable vector-borne diseases reported in 2017 were linked to ticks.² Geographic ranges of multiple tick species continue to expand, which is thought to be secondary to rising global temperatures, ecologic changes, reforestation, and increases in commerce and travel (Figure 4).³ Not only have warming temperatures contributed to geographic range expansion, they also may extend ticks’ active season. The lone star tick (Amblyomma americanum) is widely distributed throughout much of the eastern United States.⁴ The range of A americanum has expanded north in recent years from its prior core range in the southeastern United States.² One study found that from 2006 to 2016, the vector tick species most commonly collected from humans and submitted to a tick surveillance system in New Jersey shifted from Ixodes scapularis to A americanum.⁵

Bites by Amblyomma Ticks—As with most hard ticks, the life cycle of A americanum lasts 2 years and includes the egg, the 6-legged larva or “seed tick,” the 8-legged immature nymph, and the 8-legged reproductively mature adult (Figure 3). Amblyomma americanum can lay several thousand eggs.² Because our patient had numerous bites, it is plausible that she came into contact with a nest of newly hatched tick larvae. Morphogenesis from larva to nymph, then nymph to adult, requires a blood meal.^6,7 The larvae emerge from eggs deposited on the ground and then crawl up low vegetation where they can easily attach to passing hosts. The tick clings to hair or clothing and waits until the host is at rest before moving to a favorable location and then bites.⁸ When attaching, ticks inject an anesthetic akin to lidocaine, making the bite painless. A tick may spend up to 24 hours on the host prior to biting and then feed for 2 hours to 7 days before releasing.⁹ For the majority of tick-borne illnesses, the tick must remain attached for 24 to 48 hours before disease is transmitted.¹⁰

All stages of Amblyomma, excluding the egg, are capable of transmitting disease.^8,11Amblyomma americanum is called the lone star tick because of the prominent white dot on the back of the adult female. It will feed on small or large mammals during any stage of its life cycle. It is known to transmit Ehrlichia chaffeensis and Ehrlichia ewingii, which cause human ehrlichiosis, and Francisella tularensis, which causes tularemia, Heartland virus, Bourbon virus, and Southern tick-associated rash illness. Delayed anaphylaxis to ingestion of red meat has been attributed to the bite of A americanum. Amblyomma americanum ticks are not known to transmit Lyme disease. The Centers for Disease Control and Prevention does not recommend prophylactic treatment to prevent ehrlichiosis.¹² Tularemia prophylaxis is only recommended in cases of laboratory exposure to infectious materials. Doxycycline prophylaxis is only recommended if the tick is identified as an adult or nymphal I scapularis.¹²

Even when the ticks do not transmit disease, tick bites can cause impressive local reactions. Uncomplicated bites can be painful and leave a puncture wound that can take 1 to 2 weeks to heal.¹³ Rarely, bites can cause a delayed hypersensitivity reaction including fever, pruritus, and urticaria. Granulomas can develop if a tick is improperly removed.⁹ Other reports describe prurigo lesions, skin hemorrhage, papular urticaria, diffuse papules, vesicles and bullae, necrotic ulcers, and patchy alopecia.^14,15 A 2015 systematic controlled study of human bite reactions from A americanum demonstrated the development of itchy erythematous papules and vesicles within 48 hours of larval tick attachment to research participants. The study found tissue damage from A americanum mouthparts, and degranulating mast cells may be evident in as little as 15 minutes.¹⁶ The severity of individual skin reaction is hypothesized to depend on several variables, such as the duration of feeding, size of mouthparts, type of tick secretions, changes in secretions during feeding, and prior exposures of the host.¹⁴

Tick Removal—If patients present to clinic with ticks attached, removal can be challenging. Removal recommendations call for use of blunt forceps or tweezers. Ticks should be grasped near the skin with consistent pressure, and the tick should be pulled straight out, perpendicular to the skin. Twisting motions can cause the head to separate from the body and remain in the bite wound. Immediately following removal, the area should be cleansed with a disinfectant.^10,17 After the tick is removed, some studies recommend storing the tick at −20 °C; should the patient develop disease, the tick could be sent for evaluation.^6,17 If there is no clinical or serologic evidence of infection, testing for the presence of antibodies against tick-borne bacteria at presentation and at 3 and 6 weeks is not recommended due to low sensitivity, low positive predictive value, and cost. Clinicians must only observe and treat if disease occurs.¹⁷

Prevention of Tick Bites—Tick bites are best prevented by avoiding tick-infested areas; when these areas are unavoidable, tick bites may be prevented by wearing long pants with the pant legs tucked into boots. In addition, applying topical DEET (N,N-diethyl-m-toluamide) repellent to exposed skin and treating clothing with permethrin can be helpful.¹⁷ When used alone, DEET provides greater than 90% protection for up to 2.7 hours against A americanum.¹⁸ Permethrin-treated clothing alone is 79% to 100% effective at killing A americanum ticks or disabling them for several hours.¹⁹

Conclusion

Tick-borne illness is an increasingly important cause of human infectious disease. In addition to their role as a disease vector, ticks can produce primary skin disorders. This case posed a diagnostic challenge because of the unusually large number and wide distribution of bites as well as the subsequent vesicular reaction that ensued. It is important to keep tick larvae or adult tick bites in the differential when evaluating a patient to expedite tick removal and begin clinical monitoring. Recognition of A americanum larvae as a potential cause of pruritic papules may be helpful in similar cases. In addition, it is important for dermatologists to be aware of the tick species in their area.

Angioimmunoblastic T-cell lymphoma (AITL) is a rare and aggressive lymphoma arising from follicular T-helper cells that predominantly affects older adults and carries a 5-year overall survival rate of 32%.¹ Notably, as many as 50% of AITL patients present with a skin rash in addition to the more common but nonspecific acute-onset generalized lymphadenopathy, hepatosplenomegaly, and anemia.² At presentation, most AITL patients are already at an advanced (III/IV) stage of disease.

Formerly known as angioimmunoblastic lymphadenopathy with dysproteinemia, AITL was once considered a benign entity that carried a risk for malignant transformation. As more cases have been identified and explored, this entity has been recategorized as a frank lymphoma.³ Therefore, it is critical that AITL be diagnosed and treated as early as possible.

We present the case of a 65-year-old man with clinical features that resembled drug reaction with eosinophilia and systemic symptoms (DRESS syndrome). After extensive workup, he was found to have AITL. This atypical case highlights the importance of maintaining a flexible differential diagnosis in patients with a persistent rash that does not improve with appropriate drug withdrawal and therapy.

Case Report

A 65-year-old Filipino man whose medical history was notable for hepatitis B that had been treated with entecavir for years without issue was admitted to the internal medicine service with fever of unknown origin and malaise of approximately 6 weeks’ duration. Six days prior to admission and 5 days after completing courses of the antiviral oseltamivir phosphate and amoxicillin for an upper respiratory tract infection and sinusitis, he developed worsening of an intermittently pruritic rash of approximately 1 month's duration. The dermatology department was consulted the day of hospital admission for evaluation of the rash. Chronic home medications included entecavir, lisinopril/hydrochlorothiazide, amlodipine, atorvastatin, metformin, salsalate, and over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) as needed.

Physical examination was notable for mild erythema and scale distributed across the entire face; mild facial edema; and a blanchable, nonconfluent, macular erythema distributed across the trunk and upper and proximal lower extremities (Figure). In addition, the patient displayed conjunctival injection, pitting edema of the hands, and bilateral cervical and inguinal lymphadenopathy.

Photographs courtesy of James Contestable, MD (Camp Lejeune, North Carolina).

Laboratory tests revealed mild leukocytosis (11.6×10⁹/L, [reference range, 4.0–10.5×10⁹/L]), anemia (hemoglobin, 125 g/L (reference range, 138–170 g/L); hematocrit, 36.9%, [reference range, 40.0%–50.0%)], eosinophilia (1.07×10⁹/L [reference range, 0.00–0.70×10⁹/L)], hyponatremia, hypokalemia, and a mildly elevated creatinine level. Computed tomography and full-body positron-emission tomography (PET) scans during admission demonstrated diffuse lymphadenopathy. A skin biopsy from the left chest and a left inguinal lymph node biopsy also were performed.

Despite the lack of a clear medication trigger within the usual timeline for severe cutaneous drug-induced hypersensitivity reactions, DRESS syndrome was high on the differential diagnosis at the time of the initial presentation given the diffuse morbilliform eruption with pruritus, facial edema, eosinophilia, and lymphadenopathy.

Home medications were discontinued except for amlodipine, atorvastatin, and entecavir. The patient was treated symptomatically with topical steroids because it was believed that, if the clinical presentation represented DRESS syndrome, it was a mild variant that could be treated topically.⁴ His case was considered mild because of a lack of confirmed organ dysfunction and a mild protracted course.

After discharge following a 3-day inpatient stay, the patient was followed in the clinic weekly for 3 weeks without considerable change in the skin or laboratory findings. Discontinuation of entecavir was discussed and approved by his hepatologist.

Posthospitalization analysis of the punch biopsy specimen from the chest performed during the patient’s hospital stay revealed a superficial and deep dermal lymphoid infiltrate comprising CD3-, CD5-, and programmed cell death protein 1–positive cells with cytologic atypia in a perivascular distribution. Analysis of the lymph node biopsy specimen performed during the hospitalization showed effacement of the nodal architecture, a polymorphous lymphoid cell population with irregular nuclear contour, and abundant clear cytoplasm associated with high endothelial venules (HEVs). Cells of interest were positive for CD3, CD4, CD2, CD5, and CD7, with a subset staining positive for programmed cell death protein 1, inducible costimulator, CD10, and chemokine (C-X-C motif) ligand (CXCL) 13. CD21 demonstrated an expanded follicular dendritic cell meshwork in association with HEVs. Polymerase chain reaction revealed a clonal T-cell population. These findings of the skin and lymph node biopsies were consistent with AITL. Subsequent bone marrow biopsy with flow cytometry showed a normal CD4:CD8 ratio in T cells and no increase in natural killer cells.

Cyclophosphamide–hydroxydaunorubicin–Oncovin–prednisone (CHOP) chemotherapy was initiated; the patient completed a total of 6 cycles. He has had near resolution of the skin findings and is considered in remission based on a PET scan performed approximately 7 months after the initial presentation.

Comment

Angioimmunoblastic T-cell lymphoma is a rare peripheral T-cell lymphoma, part of a group of aggressive neoplasms that constitute approximately 15% of peripheral T-cell lymphomas and approximately 2% of non-Hodgkin lymphomas in adults worldwide.⁵ Cutaneous involvement occurs in approximately half of AITL cases and can be the first manifestation of disease.² Skin findings are largely nonspecific, ranging from simple morbilliform rashes to erythroderma, at times manifesting with purpura.

Given this variability in the presentation of AITL, early diagnosis is challenging in the absence of more specific signs and symptoms.² It can conceivably be mistaken for common entities such as viral exanthems or drug eruptions, depending on the history and context. DRESS syndrome, a T cell-mediated, delayed type-IV hypersensitivity drug reaction can present in a manner highly similar to that of AITL, with cutaneous involvement (diffuse morbilliform rash, fever, facial edema, and generalized lymphadenopathy) and variable systemic involvement. Laboratory findings of eosinophilia, atypical lymphocytes, and thrombocytopenia also might be seen in both entities.⁶ Furthermore, the AITL in our patient was accompanied by electrolyte disturbances that were concerning for syndrome of inappropriate antidiuretic hormone secretion, a rare complication of patients with DRESS syndrome complicated by encephalitis.^7,8

Our patient met 4 RegiSCAR criteria for DRESS syndrome, warranting high clinical suspicion for an offending drug.⁹ DRESS syndrome can be caused by numerous medications—most commonly anticonvulsants, sulfonamides, antibiotics, allopurinol, and NSAIDs. A review of our patient’s medication list identified NSAIDs (including salsalate), entecavir, and amoxicillin, as possible culpable medications. Notably, the only new addition to the patient’s regimen was amoxicillin, which did not fit the typical 2- to 8-week timeline for a DRESS syndrome nidus.¹⁰ Our patient’s fever began well before the antibiotic was initiated, and skin findings appeared within 1 week after the course of amoxicillin was completed. Although there is documented variability in the latency of onset of DRESS syndrome following administration of a culprit medication,¹¹ it is critical to maintain a broad differential diagnosis to allow for further diagnostic information to be obtained, especially when the medication timeline does not align with the clinical presentation.

DRESS syndrome is far more common than AITL. Similarities in their clinical presentation pose a substantial challenge and often cause a delay in the diagnosis of AITL, which is made by excisional tissue biopsy, most commonly of a lymph node, with assessment of morphology and immunophenotyping. Histologic assessment of tissue reveals a polymorphous infiltrate of variably sized atypical lymphocytes with prominent arborizing HEVs as well as expanded populations of follicular dendritic cells that can be detected by CD21 staining. Cells express CD3 and CD4, variably express BCL6 (B-cell lymphoma 6 antigen) and CD10, and also may have partial or complete loss of expression of a subset of pan T-cell antigens (CD2, CD3, CD5, and CD7).^12-18

The treatment approach to AITL mirrors that of other nodal peripheral T-cell lymphomas, including chemotherapy and consideration of autologous stem-cell transplantation. Recent prospective trials of CHOP and CHOP-like chemotherapy have reported 3-year event-free survival and overall survival rates of 50% and 68%, respectively.¹⁹ Novel chemotherapeutic targets and gene-expression profiling are being investigated as potential therapeutic avenues.²⁰

Conclusion

DRESS syndrome and AITL can have near-identical presentations. Clinicians should maintain a high index of suspicion for AITL in patients with presumed DRESS syndrome whose rash does not improve with appropriate drug withdrawal and steroid therapy or who lack a strong offending medication history. In such cases, skin and lymph node biopsies should be performed as early as possible to evaluate for AITL and so that appropriate therapy can be initiated.

Angioimmunoblastic T-cell lymphoma (AITL) is a rare and aggressive lymphoma arising from follicular T-helper cells that predominantly affects older adults and carries a 5-year overall survival rate of 32%.¹ Notably, as many as 50% of AITL patients present with a skin rash in addition to the more common but nonspecific acute-onset generalized lymphadenopathy, hepatosplenomegaly, and anemia.² At presentation, most AITL patients are already at an advanced (III/IV) stage of disease.

Formerly known as angioimmunoblastic lymphadenopathy with dysproteinemia, AITL was once considered a benign entity that carried a risk for malignant transformation. As more cases have been identified and explored, this entity has been recategorized as a frank lymphoma.³ Therefore, it is critical that AITL be diagnosed and treated as early as possible.

We present the case of a 65-year-old man with clinical features that resembled drug reaction with eosinophilia and systemic symptoms (DRESS syndrome). After extensive workup, he was found to have AITL. This atypical case highlights the importance of maintaining a flexible differential diagnosis in patients with a persistent rash that does not improve with appropriate drug withdrawal and therapy.

Case Report

A 65-year-old Filipino man whose medical history was notable for hepatitis B that had been treated with entecavir for years without issue was admitted to the internal medicine service with fever of unknown origin and malaise of approximately 6 weeks’ duration. Six days prior to admission and 5 days after completing courses of the antiviral oseltamivir phosphate and amoxicillin for an upper respiratory tract infection and sinusitis, he developed worsening of an intermittently pruritic rash of approximately 1 month's duration. The dermatology department was consulted the day of hospital admission for evaluation of the rash. Chronic home medications included entecavir, lisinopril/hydrochlorothiazide, amlodipine, atorvastatin, metformin, salsalate, and over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) as needed.

Physical examination was notable for mild erythema and scale distributed across the entire face; mild facial edema; and a blanchable, nonconfluent, macular erythema distributed across the trunk and upper and proximal lower extremities (Figure). In addition, the patient displayed conjunctival injection, pitting edema of the hands, and bilateral cervical and inguinal lymphadenopathy.

Photographs courtesy of James Contestable, MD (Camp Lejeune, North Carolina).

Laboratory tests revealed mild leukocytosis (11.6×10⁹/L, [reference range, 4.0–10.5×10⁹/L]), anemia (hemoglobin, 125 g/L (reference range, 138–170 g/L); hematocrit, 36.9%, [reference range, 40.0%–50.0%)], eosinophilia (1.07×10⁹/L [reference range, 0.00–0.70×10⁹/L)], hyponatremia, hypokalemia, and a mildly elevated creatinine level. Computed tomography and full-body positron-emission tomography (PET) scans during admission demonstrated diffuse lymphadenopathy. A skin biopsy from the left chest and a left inguinal lymph node biopsy also were performed.

Despite the lack of a clear medication trigger within the usual timeline for severe cutaneous drug-induced hypersensitivity reactions, DRESS syndrome was high on the differential diagnosis at the time of the initial presentation given the diffuse morbilliform eruption with pruritus, facial edema, eosinophilia, and lymphadenopathy.

Home medications were discontinued except for amlodipine, atorvastatin, and entecavir. The patient was treated symptomatically with topical steroids because it was believed that, if the clinical presentation represented DRESS syndrome, it was a mild variant that could be treated topically.⁴ His case was considered mild because of a lack of confirmed organ dysfunction and a mild protracted course.

After discharge following a 3-day inpatient stay, the patient was followed in the clinic weekly for 3 weeks without considerable change in the skin or laboratory findings. Discontinuation of entecavir was discussed and approved by his hepatologist.

Posthospitalization analysis of the punch biopsy specimen from the chest performed during the patient’s hospital stay revealed a superficial and deep dermal lymphoid infiltrate comprising CD3-, CD5-, and programmed cell death protein 1–positive cells with cytologic atypia in a perivascular distribution. Analysis of the lymph node biopsy specimen performed during the hospitalization showed effacement of the nodal architecture, a polymorphous lymphoid cell population with irregular nuclear contour, and abundant clear cytoplasm associated with high endothelial venules (HEVs). Cells of interest were positive for CD3, CD4, CD2, CD5, and CD7, with a subset staining positive for programmed cell death protein 1, inducible costimulator, CD10, and chemokine (C-X-C motif) ligand (CXCL) 13. CD21 demonstrated an expanded follicular dendritic cell meshwork in association with HEVs. Polymerase chain reaction revealed a clonal T-cell population. These findings of the skin and lymph node biopsies were consistent with AITL. Subsequent bone marrow biopsy with flow cytometry showed a normal CD4:CD8 ratio in T cells and no increase in natural killer cells.

Cyclophosphamide–hydroxydaunorubicin–Oncovin–prednisone (CHOP) chemotherapy was initiated; the patient completed a total of 6 cycles. He has had near resolution of the skin findings and is considered in remission based on a PET scan performed approximately 7 months after the initial presentation.

Comment

Angioimmunoblastic T-cell lymphoma is a rare peripheral T-cell lymphoma, part of a group of aggressive neoplasms that constitute approximately 15% of peripheral T-cell lymphomas and approximately 2% of non-Hodgkin lymphomas in adults worldwide.⁵ Cutaneous involvement occurs in approximately half of AITL cases and can be the first manifestation of disease.² Skin findings are largely nonspecific, ranging from simple morbilliform rashes to erythroderma, at times manifesting with purpura.

Given this variability in the presentation of AITL, early diagnosis is challenging in the absence of more specific signs and symptoms.² It can conceivably be mistaken for common entities such as viral exanthems or drug eruptions, depending on the history and context. DRESS syndrome, a T cell-mediated, delayed type-IV hypersensitivity drug reaction can present in a manner highly similar to that of AITL, with cutaneous involvement (diffuse morbilliform rash, fever, facial edema, and generalized lymphadenopathy) and variable systemic involvement. Laboratory findings of eosinophilia, atypical lymphocytes, and thrombocytopenia also might be seen in both entities.⁶ Furthermore, the AITL in our patient was accompanied by electrolyte disturbances that were concerning for syndrome of inappropriate antidiuretic hormone secretion, a rare complication of patients with DRESS syndrome complicated by encephalitis.^7,8

Our patient met 4 RegiSCAR criteria for DRESS syndrome, warranting high clinical suspicion for an offending drug.⁹ DRESS syndrome can be caused by numerous medications—most commonly anticonvulsants, sulfonamides, antibiotics, allopurinol, and NSAIDs. A review of our patient’s medication list identified NSAIDs (including salsalate), entecavir, and amoxicillin, as possible culpable medications. Notably, the only new addition to the patient’s regimen was amoxicillin, which did not fit the typical 2- to 8-week timeline for a DRESS syndrome nidus.¹⁰ Our patient’s fever began well before the antibiotic was initiated, and skin findings appeared within 1 week after the course of amoxicillin was completed. Although there is documented variability in the latency of onset of DRESS syndrome following administration of a culprit medication,¹¹ it is critical to maintain a broad differential diagnosis to allow for further diagnostic information to be obtained, especially when the medication timeline does not align with the clinical presentation.

DRESS syndrome is far more common than AITL. Similarities in their clinical presentation pose a substantial challenge and often cause a delay in the diagnosis of AITL, which is made by excisional tissue biopsy, most commonly of a lymph node, with assessment of morphology and immunophenotyping. Histologic assessment of tissue reveals a polymorphous infiltrate of variably sized atypical lymphocytes with prominent arborizing HEVs as well as expanded populations of follicular dendritic cells that can be detected by CD21 staining. Cells express CD3 and CD4, variably express BCL6 (B-cell lymphoma 6 antigen) and CD10, and also may have partial or complete loss of expression of a subset of pan T-cell antigens (CD2, CD3, CD5, and CD7).^12-18

The treatment approach to AITL mirrors that of other nodal peripheral T-cell lymphomas, including chemotherapy and consideration of autologous stem-cell transplantation. Recent prospective trials of CHOP and CHOP-like chemotherapy have reported 3-year event-free survival and overall survival rates of 50% and 68%, respectively.¹⁹ Novel chemotherapeutic targets and gene-expression profiling are being investigated as potential therapeutic avenues.²⁰

Conclusion

DRESS syndrome and AITL can have near-identical presentations. Clinicians should maintain a high index of suspicion for AITL in patients with presumed DRESS syndrome whose rash does not improve with appropriate drug withdrawal and steroid therapy or who lack a strong offending medication history. In such cases, skin and lymph node biopsies should be performed as early as possible to evaluate for AITL and so that appropriate therapy can be initiated.

Angioimmunoblastic T-cell lymphoma (AITL) is a rare and aggressive lymphoma arising from follicular T-helper cells that predominantly affects older adults and carries a 5-year overall survival rate of 32%.¹ Notably, as many as 50% of AITL patients present with a skin rash in addition to the more common but nonspecific acute-onset generalized lymphadenopathy, hepatosplenomegaly, and anemia.² At presentation, most AITL patients are already at an advanced (III/IV) stage of disease.

Formerly known as angioimmunoblastic lymphadenopathy with dysproteinemia, AITL was once considered a benign entity that carried a risk for malignant transformation. As more cases have been identified and explored, this entity has been recategorized as a frank lymphoma.³ Therefore, it is critical that AITL be diagnosed and treated as early as possible.

We present the case of a 65-year-old man with clinical features that resembled drug reaction with eosinophilia and systemic symptoms (DRESS syndrome). After extensive workup, he was found to have AITL. This atypical case highlights the importance of maintaining a flexible differential diagnosis in patients with a persistent rash that does not improve with appropriate drug withdrawal and therapy.

Case Report

A 65-year-old Filipino man whose medical history was notable for hepatitis B that had been treated with entecavir for years without issue was admitted to the internal medicine service with fever of unknown origin and malaise of approximately 6 weeks’ duration. Six days prior to admission and 5 days after completing courses of the antiviral oseltamivir phosphate and amoxicillin for an upper respiratory tract infection and sinusitis, he developed worsening of an intermittently pruritic rash of approximately 1 month's duration. The dermatology department was consulted the day of hospital admission for evaluation of the rash. Chronic home medications included entecavir, lisinopril/hydrochlorothiazide, amlodipine, atorvastatin, metformin, salsalate, and over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) as needed.

Physical examination was notable for mild erythema and scale distributed across the entire face; mild facial edema; and a blanchable, nonconfluent, macular erythema distributed across the trunk and upper and proximal lower extremities (Figure). In addition, the patient displayed conjunctival injection, pitting edema of the hands, and bilateral cervical and inguinal lymphadenopathy.

Photographs courtesy of James Contestable, MD (Camp Lejeune, North Carolina).

Laboratory tests revealed mild leukocytosis (11.6×10⁹/L, [reference range, 4.0–10.5×10⁹/L]), anemia (hemoglobin, 125 g/L (reference range, 138–170 g/L); hematocrit, 36.9%, [reference range, 40.0%–50.0%)], eosinophilia (1.07×10⁹/L [reference range, 0.00–0.70×10⁹/L)], hyponatremia, hypokalemia, and a mildly elevated creatinine level. Computed tomography and full-body positron-emission tomography (PET) scans during admission demonstrated diffuse lymphadenopathy. A skin biopsy from the left chest and a left inguinal lymph node biopsy also were performed.

Despite the lack of a clear medication trigger within the usual timeline for severe cutaneous drug-induced hypersensitivity reactions, DRESS syndrome was high on the differential diagnosis at the time of the initial presentation given the diffuse morbilliform eruption with pruritus, facial edema, eosinophilia, and lymphadenopathy.

Home medications were discontinued except for amlodipine, atorvastatin, and entecavir. The patient was treated symptomatically with topical steroids because it was believed that, if the clinical presentation represented DRESS syndrome, it was a mild variant that could be treated topically.⁴ His case was considered mild because of a lack of confirmed organ dysfunction and a mild protracted course.

After discharge following a 3-day inpatient stay, the patient was followed in the clinic weekly for 3 weeks without considerable change in the skin or laboratory findings. Discontinuation of entecavir was discussed and approved by his hepatologist.

Posthospitalization analysis of the punch biopsy specimen from the chest performed during the patient’s hospital stay revealed a superficial and deep dermal lymphoid infiltrate comprising CD3-, CD5-, and programmed cell death protein 1–positive cells with cytologic atypia in a perivascular distribution. Analysis of the lymph node biopsy specimen performed during the hospitalization showed effacement of the nodal architecture, a polymorphous lymphoid cell population with irregular nuclear contour, and abundant clear cytoplasm associated with high endothelial venules (HEVs). Cells of interest were positive for CD3, CD4, CD2, CD5, and CD7, with a subset staining positive for programmed cell death protein 1, inducible costimulator, CD10, and chemokine (C-X-C motif) ligand (CXCL) 13. CD21 demonstrated an expanded follicular dendritic cell meshwork in association with HEVs. Polymerase chain reaction revealed a clonal T-cell population. These findings of the skin and lymph node biopsies were consistent with AITL. Subsequent bone marrow biopsy with flow cytometry showed a normal CD4:CD8 ratio in T cells and no increase in natural killer cells.

Cyclophosphamide–hydroxydaunorubicin–Oncovin–prednisone (CHOP) chemotherapy was initiated; the patient completed a total of 6 cycles. He has had near resolution of the skin findings and is considered in remission based on a PET scan performed approximately 7 months after the initial presentation.

Comment

Angioimmunoblastic T-cell lymphoma is a rare peripheral T-cell lymphoma, part of a group of aggressive neoplasms that constitute approximately 15% of peripheral T-cell lymphomas and approximately 2% of non-Hodgkin lymphomas in adults worldwide.⁵ Cutaneous involvement occurs in approximately half of AITL cases and can be the first manifestation of disease.² Skin findings are largely nonspecific, ranging from simple morbilliform rashes to erythroderma, at times manifesting with purpura.

Given this variability in the presentation of AITL, early diagnosis is challenging in the absence of more specific signs and symptoms.² It can conceivably be mistaken for common entities such as viral exanthems or drug eruptions, depending on the history and context. DRESS syndrome, a T cell-mediated, delayed type-IV hypersensitivity drug reaction can present in a manner highly similar to that of AITL, with cutaneous involvement (diffuse morbilliform rash, fever, facial edema, and generalized lymphadenopathy) and variable systemic involvement. Laboratory findings of eosinophilia, atypical lymphocytes, and thrombocytopenia also might be seen in both entities.⁶ Furthermore, the AITL in our patient was accompanied by electrolyte disturbances that were concerning for syndrome of inappropriate antidiuretic hormone secretion, a rare complication of patients with DRESS syndrome complicated by encephalitis.^7,8

Our patient met 4 RegiSCAR criteria for DRESS syndrome, warranting high clinical suspicion for an offending drug.⁹ DRESS syndrome can be caused by numerous medications—most commonly anticonvulsants, sulfonamides, antibiotics, allopurinol, and NSAIDs. A review of our patient’s medication list identified NSAIDs (including salsalate), entecavir, and amoxicillin, as possible culpable medications. Notably, the only new addition to the patient’s regimen was amoxicillin, which did not fit the typical 2- to 8-week timeline for a DRESS syndrome nidus.¹⁰ Our patient’s fever began well before the antibiotic was initiated, and skin findings appeared within 1 week after the course of amoxicillin was completed. Although there is documented variability in the latency of onset of DRESS syndrome following administration of a culprit medication,¹¹ it is critical to maintain a broad differential diagnosis to allow for further diagnostic information to be obtained, especially when the medication timeline does not align with the clinical presentation.

DRESS syndrome is far more common than AITL. Similarities in their clinical presentation pose a substantial challenge and often cause a delay in the diagnosis of AITL, which is made by excisional tissue biopsy, most commonly of a lymph node, with assessment of morphology and immunophenotyping. Histologic assessment of tissue reveals a polymorphous infiltrate of variably sized atypical lymphocytes with prominent arborizing HEVs as well as expanded populations of follicular dendritic cells that can be detected by CD21 staining. Cells express CD3 and CD4, variably express BCL6 (B-cell lymphoma 6 antigen) and CD10, and also may have partial or complete loss of expression of a subset of pan T-cell antigens (CD2, CD3, CD5, and CD7).^12-18

The treatment approach to AITL mirrors that of other nodal peripheral T-cell lymphomas, including chemotherapy and consideration of autologous stem-cell transplantation. Recent prospective trials of CHOP and CHOP-like chemotherapy have reported 3-year event-free survival and overall survival rates of 50% and 68%, respectively.¹⁹ Novel chemotherapeutic targets and gene-expression profiling are being investigated as potential therapeutic avenues.²⁰

Conclusion

DRESS syndrome and AITL can have near-identical presentations. Clinicians should maintain a high index of suspicion for AITL in patients with presumed DRESS syndrome whose rash does not improve with appropriate drug withdrawal and steroid therapy or who lack a strong offending medication history. In such cases, skin and lymph node biopsies should be performed as early as possible to evaluate for AITL and so that appropriate therapy can be initiated.

Subacute combined degeneration (SCD) is an acquired neurologic complication of vitamin B12 (cobalamin) or, rarely, vitamin B9 (folate) deficiency. SCD is characterized by progressive demyelination of the dorsal and lateral spinal cord, resulting in peripheral neuropathy; gait ataxia; impaired proprioception, vibration, and fine touch; optic neuropathy; and cognitive impairment.¹ In addition to SCD, other neurologic manifestations of B12 deficiency include dementia, depression, visual symptoms due to optic atrophy, and behavioral changes.² The prevalence of SCD in the US has not been well documented, but B12 deficiency is reported at 6% in those aged < 60 years and 20% in those > 60 years^.3

Causes of B12 and B9 deficiency include advanced age, low nutritional intake (eg, vegan diet), impaired absorption (eg, inflammatory bowel disease, autoimmune pernicious anemia, gastrectomy, pancreatic disease), alcohol use, tapeworm infection, medications, and high metabolic states.^2,4 Impaired B12 absorption is common in patients taking medications, such as metformin and proton pump inhibitors (PPI), due to suppression of ileal membrane transport and intrinsic factor activity.^5-7 B-vitamin deficiency can be exacerbated by states of increased cellular turnover, such as polycythemia vera, due to elevated DNA synthesis.

Patients may experience permanent neurologic damage when the diagnosis and treatment of SCD are missed or delayed. Early diagnosis of SCD can be challenging due to lack of specific hematologic markers. In addition, many other conditions such as diabetic neuropathy, malnutrition, toxic neuropathy, sarcoidosis, HIV, multiple sclerosis, polycythemia vera, and iron deficiency anemia have similar presentations and clinical findings.⁸ Anemia and/or macrocytosis are not specific to B12 deficiency.⁴ In addition, patients with B12 deficiency may have a normal complete blood count (CBC); those with concomitant iron deficiency may have minimal or no mean corpuscular volume (MCV) elevation.⁴ In patients suspected to have B12 deficiency based on clinical presentation or laboratory findings of macrocytosis, serum methylmalonic acid (MMA) can serve as a direct measure of B12 activity, with levels > 0.75 μmol/L almost always indicating cobalamin deficiency. ⁹ On the other hand, plasma total homocysteine (tHcy) is a sensitive marker for B12 deficiency. The active form of B12, holotranscobalamin, has also emerged as a specific measure of B12 deficiency.⁹ However, in patients with SCD, measurement of these markers may be unnecessary due to the severity of their clinical symptoms. 

The diagnosis of SCD is further complicated because not all individuals who develop B12 or B9 deficiency will develop SCD. It is difficult to determine which patients will develop SCD because the minimum level of serum B12 required for normal function is unknown, and recent studies indicate that SCD may occur even at low-normal B12 and B9 levels.^2,4,10 Commonly, a serum B12 level of < 200 pg/mL is considered deficient, while a level between 200 and 300 pg/mL is considered borderline.⁴ The goal level of serum B12 is > 300 pg/mL, which is considered normal.⁴ While serologic findings of B-vitamin deficiency are only moderately specific, radiographic findings are highly sensitive and specific for SCD. According to Briani and colleagues, the most consistent finding in SCD on magnetic resonance imaging (MRI) is a “symmetrical, abnormally increased T2 signal intensity, commonly confined to posterior or posterior and lateral columns in the cervical and thoracic spinal cord.”²

We present a case of SCD in a patient with low-normal vitamin B12 levels who presented with progressive sensorimotor deficits and vision loss. The patient was subsequently diagnosed with SCD by radiologic workup. His course was complicated by worsening neurologic deficits despite B12 replacement. The progression of his clinical symptoms demonstrates the need for prompt, aggressive B12 replacement in patients diagnosed with SCD.

Case Presentation

A 63-year-old man presented for neurologic evaluation of progressive gait disturbance, paresthesia, blurred vision, and increasing falls despite use of a walker. Pertinent medical history included polycythemia vera requiring phlebotomy for approximately 9 years, alcohol use disorder (18 servings weekly), type 2 diabetes mellitus, and a remote episode of transient ischemic attack (TIA). The patient reported a 5-year history of burning pain in all extremities. A prior physician diagnosis attributed the symptoms to polyneuropathy secondary to iron deficiency anemia in the setting of chronic phlebotomy for polycythemia vera and high erythrogenesis. He was prescribed gabapentin 600 mg 3 times daily for pain control. B12 deficiency was considered an unlikely etiology due to a low-normal serum level of 305 pg/mL (reference range, 190-950 pg/mL) and normocytosis, with MCV of 88 fL (reference range, 80-100 fL). The patient also reported a 3-year history of blurred vision, which was initially attributed to be secondary to diabetic retinopathy. One week prior to presenting to our clinic, he was evaluated by ophthalmology for new-onset, bilateral central visual field defects, and he was diagnosed with nutritional optic neuropathy.

Previous cardiac evaluation failed to provide a diagnosis for syncopal episodes. MRI of the brain revealed nonspecific white matter changes consistent with chronic microvascular ischemic disease. Electromyography was limited due to pain but showed severe peripheral neuropathy. Laboratory results showed megalocytosis, low-normal serum B12 levels, and low serum folate levels (Table 2). The patient was diagnosed with polyneuropathy and was given intramuscular (IM) vitamin B12 1000 mcg once and a daily multivitamin (containing 25 mcg of B12). He was counseled on alcohol abstinence and medication adherence and was scheduled for follow-up in 3 months. He continued outpatient phlebotomy every 6 weeks for polycythemia.

At 3-month follow-up, the patient reported medication adherence, continued alcohol use, and worsening of symptoms. Falls, which now occurred 2 to 3 times weekly despite proper use of a walker, were described as sudden loss of bilateral lower extremity strength without loss of consciousness, palpitations, or other prodrome. Laboratory results showed minimal changes. Physical examination of the patient demonstrated similar deficits as on initial presentation. The patient received one additional B12 1000 mcg IM. Gabapentin was replaced with pregabalin 75 mg twice daily due to persistent uncontrolled pain and paresthesia. The patient was scheduled for a 3-month followup (6 months from initial visit) and repeat serology.

At 6-month follow-up, the patient showed continued progression of disease with significant difficulty using the walker, worsening falls, and wheelchair use required. Physical examination showed decreased sensation bilaterally up to the knees, absent bilateral patellar and Achilles reflexes, and unsteady gait. Laboratory results showed persistent subclinical B12 deficiency. MRI of the brain and spine showed high T2 signaling in a pattern highly specific for SCD. A formal diagnosis of SCD was made. The patient received an additional B12 1000 mcg IM once. Follow-up phone call with the patient 1 month later revealed no progression or improvement of symptoms.

Radiographic Findings

MRI of the cervical and thoracic spine demonstrated abnormal high T2 signal starting from C2 and extending along the course of the cervical and thoracic spinal cord (Figure). MRI in SCD classically shows symmetric, bilateral high T2 signal within the dorsal columns; on axial images, there is typically an inverted “V” sign.^2,4 There can also be abnormal cerebral white matter change; however, MRI of the brain in this patient did not show any abnormalities.2 The imaging differential for this appearance includes other metabolic deficiencies/toxicities: copper deficiency; vitamin E deficiency; methotrexateinduced myelopathy, and infectious causes: HIV vacuolar myelopathy; and neurosyphilis (tabes dorsalis).⁴

Discussion

This case demonstrates the clinical and radiographic findings of SCD and underscores the need for high-intensity dosing of B12 replacement in patients with SCD to prevent progression of the disease and development of morbidities.

Symptoms of SCD may manifest even when the vitamin levels are in low-normal levels. Its presentation is often nonspecific, thus radiologic workup is beneficial to elucidate the clinical picture. We support the use of spinal MRI in patients with clinical suspicion of SCD to help rule out other causes of myelopathy. However, an MRI is not indicated in all patients with B12 deficiency, especially those without myelopathic symptoms. Additionally, follow-up spinal MRIs are useful in monitoring the progression or improvement of SCD after B12 replacement.² It is important to note that the MRI findings in SCD are not specific to B12 deficiency; other causes may present with similar radiographic findings.⁴ Therefore, radiologic findings must be correlated with a patient’s clinical presentation.

B12 replacement improves and may resolve clinical symptoms and abnormal radiographic findings of SCD. The treatment duration of B12 deficiency depends on the underlying etiology. Reversible causes, such as metformin use > 4 months, PPI use > 12 months, and dietary deficiency, require treatment until appropriate levels are reached and symptoms are resolved.^4,11 The need for chronic metformin and PPI use should also be reassessed regularly. In patients who require long-term metformin use, IM administration of B12 1000 mcg annually should be considered, which will ensure adequate storage for more than 1 year.^12,13 In patients who require long-term PPI use, the risk and benefits of continued use should be measured, and if needed, the lowest possible effective PPI dose is recommended.¹⁴ Irreversible causes of B12 deficiency, such as advanced age, prior gastrectomy, chronic pancreatitis, or autoimmune pernicious anemia, require lifelong supplementation of B12.^4,11

In general, oral vitamin B12 replacement at 1000 to 2000 mcg daily may be as effective as parenteral replacement in patients with mild to moderate deficiency or neurologic symptoms.¹¹ On the other hand, patients with SCD often require parenteral replacement of B12 due to the severity of their deficiency or neurologic symptoms, need for more rapid improvement in symptoms, and prevention of irreversible neurological deficits. ^4,11 Appropriate B12 replacement in SCD requires intensive initial therapy which may involve IM B12 1000 mcg every other day for 2 weeks and additional IM supplementation every 2 to 3 months afterward until resolution of deficiency.^4,14 IM replacement may also be considered in patients who are nonadherent to oral replacement or have an underlying gastrointestinal condition that impairs enteral absorption.^4,11

B12 deficiency is frequently undertreated and can lead to progression of disease with significant morbidity. The need for highintensity dosing of B12 replacement is crucial in patients with SCD. Failure to respond to treatment, as shown from the lack of improvement of serum markers or symptoms, likely suggests undertreatment, treatment nonadherence, iron deficiency anemia, an unidentified malabsorption syndrome, or other diagnoses. In our case, significant undertreatment, compounded by his suspected iron deficiency anemia secondary to his polycythemia vera and chronic phlebotomies, are the most likel etiologies for his lack of clinical improvement.

Multiple factors may affect the prognosis of SCD. Males aged < 50 years with absence of anemia, spinal cord atrophy, Romberg sign, Babinski sign, or sensory deficits on examination have increased likelihood of eventual recovery of signs and symptoms of SCD; those with less spinal cord involvement (< 7 cord segments), contrast enhancement, and spinal cord edema also have improved outcomes.^4,15

Conclusion

SCD is a rare but serious complication of chronic vitamin B12 deficiency that presents with a variety of neurological findings and may be easily confused with other illnesses. The condition is easily overlooked or misdiagnosed; thus, it is crucial to differentiate B12 deficiency from other common causes of neurologic symptoms. Specific findings on MRI are useful to support the clinical diagnosis of SCD and guide clinical decisions. Given the prevalence of B12 deficiency in the older adult population, clinicians should remain alert to the possibility of these conditions in patients who present with progressive neuropathy. Once a patient is diagnosed with SCD secondary to a B12 deficiency, appropriate B12 replacement is critical. Appropriate B12 replacement is aggressive and involves IM B12 1000 mcg every other day for 2 to 3 weeks, followed by additional IM administration every 2 months before transitioning to oral therapy. As seen in this case, failure to adequately replenish B12 can lead to progression or lack of resolution of SCD symptoms.

Subacute combined degeneration (SCD) is an acquired neurologic complication of vitamin B12 (cobalamin) or, rarely, vitamin B9 (folate) deficiency. SCD is characterized by progressive demyelination of the dorsal and lateral spinal cord, resulting in peripheral neuropathy; gait ataxia; impaired proprioception, vibration, and fine touch; optic neuropathy; and cognitive impairment.¹ In addition to SCD, other neurologic manifestations of B12 deficiency include dementia, depression, visual symptoms due to optic atrophy, and behavioral changes.² The prevalence of SCD in the US has not been well documented, but B12 deficiency is reported at 6% in those aged < 60 years and 20% in those > 60 years^.3

Causes of B12 and B9 deficiency include advanced age, low nutritional intake (eg, vegan diet), impaired absorption (eg, inflammatory bowel disease, autoimmune pernicious anemia, gastrectomy, pancreatic disease), alcohol use, tapeworm infection, medications, and high metabolic states.^2,4 Impaired B12 absorption is common in patients taking medications, such as metformin and proton pump inhibitors (PPI), due to suppression of ileal membrane transport and intrinsic factor activity.^5-7 B-vitamin deficiency can be exacerbated by states of increased cellular turnover, such as polycythemia vera, due to elevated DNA synthesis.

Patients may experience permanent neurologic damage when the diagnosis and treatment of SCD are missed or delayed. Early diagnosis of SCD can be challenging due to lack of specific hematologic markers. In addition, many other conditions such as diabetic neuropathy, malnutrition, toxic neuropathy, sarcoidosis, HIV, multiple sclerosis, polycythemia vera, and iron deficiency anemia have similar presentations and clinical findings.⁸ Anemia and/or macrocytosis are not specific to B12 deficiency.⁴ In addition, patients with B12 deficiency may have a normal complete blood count (CBC); those with concomitant iron deficiency may have minimal or no mean corpuscular volume (MCV) elevation.⁴ In patients suspected to have B12 deficiency based on clinical presentation or laboratory findings of macrocytosis, serum methylmalonic acid (MMA) can serve as a direct measure of B12 activity, with levels > 0.75 μmol/L almost always indicating cobalamin deficiency. ⁹ On the other hand, plasma total homocysteine (tHcy) is a sensitive marker for B12 deficiency. The active form of B12, holotranscobalamin, has also emerged as a specific measure of B12 deficiency.⁹ However, in patients with SCD, measurement of these markers may be unnecessary due to the severity of their clinical symptoms. 

The diagnosis of SCD is further complicated because not all individuals who develop B12 or B9 deficiency will develop SCD. It is difficult to determine which patients will develop SCD because the minimum level of serum B12 required for normal function is unknown, and recent studies indicate that SCD may occur even at low-normal B12 and B9 levels.^2,4,10 Commonly, a serum B12 level of < 200 pg/mL is considered deficient, while a level between 200 and 300 pg/mL is considered borderline.⁴ The goal level of serum B12 is > 300 pg/mL, which is considered normal.⁴ While serologic findings of B-vitamin deficiency are only moderately specific, radiographic findings are highly sensitive and specific for SCD. According to Briani and colleagues, the most consistent finding in SCD on magnetic resonance imaging (MRI) is a “symmetrical, abnormally increased T2 signal intensity, commonly confined to posterior or posterior and lateral columns in the cervical and thoracic spinal cord.”²

We present a case of SCD in a patient with low-normal vitamin B12 levels who presented with progressive sensorimotor deficits and vision loss. The patient was subsequently diagnosed with SCD by radiologic workup. His course was complicated by worsening neurologic deficits despite B12 replacement. The progression of his clinical symptoms demonstrates the need for prompt, aggressive B12 replacement in patients diagnosed with SCD.

Case Presentation

A 63-year-old man presented for neurologic evaluation of progressive gait disturbance, paresthesia, blurred vision, and increasing falls despite use of a walker. Pertinent medical history included polycythemia vera requiring phlebotomy for approximately 9 years, alcohol use disorder (18 servings weekly), type 2 diabetes mellitus, and a remote episode of transient ischemic attack (TIA). The patient reported a 5-year history of burning pain in all extremities. A prior physician diagnosis attributed the symptoms to polyneuropathy secondary to iron deficiency anemia in the setting of chronic phlebotomy for polycythemia vera and high erythrogenesis. He was prescribed gabapentin 600 mg 3 times daily for pain control. B12 deficiency was considered an unlikely etiology due to a low-normal serum level of 305 pg/mL (reference range, 190-950 pg/mL) and normocytosis, with MCV of 88 fL (reference range, 80-100 fL). The patient also reported a 3-year history of blurred vision, which was initially attributed to be secondary to diabetic retinopathy. One week prior to presenting to our clinic, he was evaluated by ophthalmology for new-onset, bilateral central visual field defects, and he was diagnosed with nutritional optic neuropathy.

Previous cardiac evaluation failed to provide a diagnosis for syncopal episodes. MRI of the brain revealed nonspecific white matter changes consistent with chronic microvascular ischemic disease. Electromyography was limited due to pain but showed severe peripheral neuropathy. Laboratory results showed megalocytosis, low-normal serum B12 levels, and low serum folate levels (Table 2). The patient was diagnosed with polyneuropathy and was given intramuscular (IM) vitamin B12 1000 mcg once and a daily multivitamin (containing 25 mcg of B12). He was counseled on alcohol abstinence and medication adherence and was scheduled for follow-up in 3 months. He continued outpatient phlebotomy every 6 weeks for polycythemia.

At 3-month follow-up, the patient reported medication adherence, continued alcohol use, and worsening of symptoms. Falls, which now occurred 2 to 3 times weekly despite proper use of a walker, were described as sudden loss of bilateral lower extremity strength without loss of consciousness, palpitations, or other prodrome. Laboratory results showed minimal changes. Physical examination of the patient demonstrated similar deficits as on initial presentation. The patient received one additional B12 1000 mcg IM. Gabapentin was replaced with pregabalin 75 mg twice daily due to persistent uncontrolled pain and paresthesia. The patient was scheduled for a 3-month followup (6 months from initial visit) and repeat serology.

At 6-month follow-up, the patient showed continued progression of disease with significant difficulty using the walker, worsening falls, and wheelchair use required. Physical examination showed decreased sensation bilaterally up to the knees, absent bilateral patellar and Achilles reflexes, and unsteady gait. Laboratory results showed persistent subclinical B12 deficiency. MRI of the brain and spine showed high T2 signaling in a pattern highly specific for SCD. A formal diagnosis of SCD was made. The patient received an additional B12 1000 mcg IM once. Follow-up phone call with the patient 1 month later revealed no progression or improvement of symptoms.

Radiographic Findings

MRI of the cervical and thoracic spine demonstrated abnormal high T2 signal starting from C2 and extending along the course of the cervical and thoracic spinal cord (Figure). MRI in SCD classically shows symmetric, bilateral high T2 signal within the dorsal columns; on axial images, there is typically an inverted “V” sign.^2,4 There can also be abnormal cerebral white matter change; however, MRI of the brain in this patient did not show any abnormalities.2 The imaging differential for this appearance includes other metabolic deficiencies/toxicities: copper deficiency; vitamin E deficiency; methotrexateinduced myelopathy, and infectious causes: HIV vacuolar myelopathy; and neurosyphilis (tabes dorsalis).⁴

Discussion

This case demonstrates the clinical and radiographic findings of SCD and underscores the need for high-intensity dosing of B12 replacement in patients with SCD to prevent progression of the disease and development of morbidities.

Symptoms of SCD may manifest even when the vitamin levels are in low-normal levels. Its presentation is often nonspecific, thus radiologic workup is beneficial to elucidate the clinical picture. We support the use of spinal MRI in patients with clinical suspicion of SCD to help rule out other causes of myelopathy. However, an MRI is not indicated in all patients with B12 deficiency, especially those without myelopathic symptoms. Additionally, follow-up spinal MRIs are useful in monitoring the progression or improvement of SCD after B12 replacement.² It is important to note that the MRI findings in SCD are not specific to B12 deficiency; other causes may present with similar radiographic findings.⁴ Therefore, radiologic findings must be correlated with a patient’s clinical presentation.

B12 replacement improves and may resolve clinical symptoms and abnormal radiographic findings of SCD. The treatment duration of B12 deficiency depends on the underlying etiology. Reversible causes, such as metformin use > 4 months, PPI use > 12 months, and dietary deficiency, require treatment until appropriate levels are reached and symptoms are resolved.^4,11 The need for chronic metformin and PPI use should also be reassessed regularly. In patients who require long-term metformin use, IM administration of B12 1000 mcg annually should be considered, which will ensure adequate storage for more than 1 year.^12,13 In patients who require long-term PPI use, the risk and benefits of continued use should be measured, and if needed, the lowest possible effective PPI dose is recommended.¹⁴ Irreversible causes of B12 deficiency, such as advanced age, prior gastrectomy, chronic pancreatitis, or autoimmune pernicious anemia, require lifelong supplementation of B12.^4,11

In general, oral vitamin B12 replacement at 1000 to 2000 mcg daily may be as effective as parenteral replacement in patients with mild to moderate deficiency or neurologic symptoms.¹¹ On the other hand, patients with SCD often require parenteral replacement of B12 due to the severity of their deficiency or neurologic symptoms, need for more rapid improvement in symptoms, and prevention of irreversible neurological deficits. ^4,11 Appropriate B12 replacement in SCD requires intensive initial therapy which may involve IM B12 1000 mcg every other day for 2 weeks and additional IM supplementation every 2 to 3 months afterward until resolution of deficiency.^4,14 IM replacement may also be considered in patients who are nonadherent to oral replacement or have an underlying gastrointestinal condition that impairs enteral absorption.^4,11

B12 deficiency is frequently undertreated and can lead to progression of disease with significant morbidity. The need for highintensity dosing of B12 replacement is crucial in patients with SCD. Failure to respond to treatment, as shown from the lack of improvement of serum markers or symptoms, likely suggests undertreatment, treatment nonadherence, iron deficiency anemia, an unidentified malabsorption syndrome, or other diagnoses. In our case, significant undertreatment, compounded by his suspected iron deficiency anemia secondary to his polycythemia vera and chronic phlebotomies, are the most likel etiologies for his lack of clinical improvement.

Multiple factors may affect the prognosis of SCD. Males aged < 50 years with absence of anemia, spinal cord atrophy, Romberg sign, Babinski sign, or sensory deficits on examination have increased likelihood of eventual recovery of signs and symptoms of SCD; those with less spinal cord involvement (< 7 cord segments), contrast enhancement, and spinal cord edema also have improved outcomes.^4,15

Conclusion

SCD is a rare but serious complication of chronic vitamin B12 deficiency that presents with a variety of neurological findings and may be easily confused with other illnesses. The condition is easily overlooked or misdiagnosed; thus, it is crucial to differentiate B12 deficiency from other common causes of neurologic symptoms. Specific findings on MRI are useful to support the clinical diagnosis of SCD and guide clinical decisions. Given the prevalence of B12 deficiency in the older adult population, clinicians should remain alert to the possibility of these conditions in patients who present with progressive neuropathy. Once a patient is diagnosed with SCD secondary to a B12 deficiency, appropriate B12 replacement is critical. Appropriate B12 replacement is aggressive and involves IM B12 1000 mcg every other day for 2 to 3 weeks, followed by additional IM administration every 2 months before transitioning to oral therapy. As seen in this case, failure to adequately replenish B12 can lead to progression or lack of resolution of SCD symptoms.

Subacute combined degeneration (SCD) is an acquired neurologic complication of vitamin B12 (cobalamin) or, rarely, vitamin B9 (folate) deficiency. SCD is characterized by progressive demyelination of the dorsal and lateral spinal cord, resulting in peripheral neuropathy; gait ataxia; impaired proprioception, vibration, and fine touch; optic neuropathy; and cognitive impairment.¹ In addition to SCD, other neurologic manifestations of B12 deficiency include dementia, depression, visual symptoms due to optic atrophy, and behavioral changes.² The prevalence of SCD in the US has not been well documented, but B12 deficiency is reported at 6% in those aged < 60 years and 20% in those > 60 years^.3

Causes of B12 and B9 deficiency include advanced age, low nutritional intake (eg, vegan diet), impaired absorption (eg, inflammatory bowel disease, autoimmune pernicious anemia, gastrectomy, pancreatic disease), alcohol use, tapeworm infection, medications, and high metabolic states.^2,4 Impaired B12 absorption is common in patients taking medications, such as metformin and proton pump inhibitors (PPI), due to suppression of ileal membrane transport and intrinsic factor activity.^5-7 B-vitamin deficiency can be exacerbated by states of increased cellular turnover, such as polycythemia vera, due to elevated DNA synthesis.

Patients may experience permanent neurologic damage when the diagnosis and treatment of SCD are missed or delayed. Early diagnosis of SCD can be challenging due to lack of specific hematologic markers. In addition, many other conditions such as diabetic neuropathy, malnutrition, toxic neuropathy, sarcoidosis, HIV, multiple sclerosis, polycythemia vera, and iron deficiency anemia have similar presentations and clinical findings.⁸ Anemia and/or macrocytosis are not specific to B12 deficiency.⁴ In addition, patients with B12 deficiency may have a normal complete blood count (CBC); those with concomitant iron deficiency may have minimal or no mean corpuscular volume (MCV) elevation.⁴ In patients suspected to have B12 deficiency based on clinical presentation or laboratory findings of macrocytosis, serum methylmalonic acid (MMA) can serve as a direct measure of B12 activity, with levels > 0.75 μmol/L almost always indicating cobalamin deficiency. ⁹ On the other hand, plasma total homocysteine (tHcy) is a sensitive marker for B12 deficiency. The active form of B12, holotranscobalamin, has also emerged as a specific measure of B12 deficiency.⁹ However, in patients with SCD, measurement of these markers may be unnecessary due to the severity of their clinical symptoms. 

The diagnosis of SCD is further complicated because not all individuals who develop B12 or B9 deficiency will develop SCD. It is difficult to determine which patients will develop SCD because the minimum level of serum B12 required for normal function is unknown, and recent studies indicate that SCD may occur even at low-normal B12 and B9 levels.^2,4,10 Commonly, a serum B12 level of < 200 pg/mL is considered deficient, while a level between 200 and 300 pg/mL is considered borderline.⁴ The goal level of serum B12 is > 300 pg/mL, which is considered normal.⁴ While serologic findings of B-vitamin deficiency are only moderately specific, radiographic findings are highly sensitive and specific for SCD. According to Briani and colleagues, the most consistent finding in SCD on magnetic resonance imaging (MRI) is a “symmetrical, abnormally increased T2 signal intensity, commonly confined to posterior or posterior and lateral columns in the cervical and thoracic spinal cord.”²

We present a case of SCD in a patient with low-normal vitamin B12 levels who presented with progressive sensorimotor deficits and vision loss. The patient was subsequently diagnosed with SCD by radiologic workup. His course was complicated by worsening neurologic deficits despite B12 replacement. The progression of his clinical symptoms demonstrates the need for prompt, aggressive B12 replacement in patients diagnosed with SCD.

Case Presentation

A 63-year-old man presented for neurologic evaluation of progressive gait disturbance, paresthesia, blurred vision, and increasing falls despite use of a walker. Pertinent medical history included polycythemia vera requiring phlebotomy for approximately 9 years, alcohol use disorder (18 servings weekly), type 2 diabetes mellitus, and a remote episode of transient ischemic attack (TIA). The patient reported a 5-year history of burning pain in all extremities. A prior physician diagnosis attributed the symptoms to polyneuropathy secondary to iron deficiency anemia in the setting of chronic phlebotomy for polycythemia vera and high erythrogenesis. He was prescribed gabapentin 600 mg 3 times daily for pain control. B12 deficiency was considered an unlikely etiology due to a low-normal serum level of 305 pg/mL (reference range, 190-950 pg/mL) and normocytosis, with MCV of 88 fL (reference range, 80-100 fL). The patient also reported a 3-year history of blurred vision, which was initially attributed to be secondary to diabetic retinopathy. One week prior to presenting to our clinic, he was evaluated by ophthalmology for new-onset, bilateral central visual field defects, and he was diagnosed with nutritional optic neuropathy.

Previous cardiac evaluation failed to provide a diagnosis for syncopal episodes. MRI of the brain revealed nonspecific white matter changes consistent with chronic microvascular ischemic disease. Electromyography was limited due to pain but showed severe peripheral neuropathy. Laboratory results showed megalocytosis, low-normal serum B12 levels, and low serum folate levels (Table 2). The patient was diagnosed with polyneuropathy and was given intramuscular (IM) vitamin B12 1000 mcg once and a daily multivitamin (containing 25 mcg of B12). He was counseled on alcohol abstinence and medication adherence and was scheduled for follow-up in 3 months. He continued outpatient phlebotomy every 6 weeks for polycythemia.

At 3-month follow-up, the patient reported medication adherence, continued alcohol use, and worsening of symptoms. Falls, which now occurred 2 to 3 times weekly despite proper use of a walker, were described as sudden loss of bilateral lower extremity strength without loss of consciousness, palpitations, or other prodrome. Laboratory results showed minimal changes. Physical examination of the patient demonstrated similar deficits as on initial presentation. The patient received one additional B12 1000 mcg IM. Gabapentin was replaced with pregabalin 75 mg twice daily due to persistent uncontrolled pain and paresthesia. The patient was scheduled for a 3-month followup (6 months from initial visit) and repeat serology.

At 6-month follow-up, the patient showed continued progression of disease with significant difficulty using the walker, worsening falls, and wheelchair use required. Physical examination showed decreased sensation bilaterally up to the knees, absent bilateral patellar and Achilles reflexes, and unsteady gait. Laboratory results showed persistent subclinical B12 deficiency. MRI of the brain and spine showed high T2 signaling in a pattern highly specific for SCD. A formal diagnosis of SCD was made. The patient received an additional B12 1000 mcg IM once. Follow-up phone call with the patient 1 month later revealed no progression or improvement of symptoms.

Radiographic Findings

MRI of the cervical and thoracic spine demonstrated abnormal high T2 signal starting from C2 and extending along the course of the cervical and thoracic spinal cord (Figure). MRI in SCD classically shows symmetric, bilateral high T2 signal within the dorsal columns; on axial images, there is typically an inverted “V” sign.^2,4 There can also be abnormal cerebral white matter change; however, MRI of the brain in this patient did not show any abnormalities.2 The imaging differential for this appearance includes other metabolic deficiencies/toxicities: copper deficiency; vitamin E deficiency; methotrexateinduced myelopathy, and infectious causes: HIV vacuolar myelopathy; and neurosyphilis (tabes dorsalis).⁴

Discussion

This case demonstrates the clinical and radiographic findings of SCD and underscores the need for high-intensity dosing of B12 replacement in patients with SCD to prevent progression of the disease and development of morbidities.

Symptoms of SCD may manifest even when the vitamin levels are in low-normal levels. Its presentation is often nonspecific, thus radiologic workup is beneficial to elucidate the clinical picture. We support the use of spinal MRI in patients with clinical suspicion of SCD to help rule out other causes of myelopathy. However, an MRI is not indicated in all patients with B12 deficiency, especially those without myelopathic symptoms. Additionally, follow-up spinal MRIs are useful in monitoring the progression or improvement of SCD after B12 replacement.² It is important to note that the MRI findings in SCD are not specific to B12 deficiency; other causes may present with similar radiographic findings.⁴ Therefore, radiologic findings must be correlated with a patient’s clinical presentation.

B12 replacement improves and may resolve clinical symptoms and abnormal radiographic findings of SCD. The treatment duration of B12 deficiency depends on the underlying etiology. Reversible causes, such as metformin use > 4 months, PPI use > 12 months, and dietary deficiency, require treatment until appropriate levels are reached and symptoms are resolved.^4,11 The need for chronic metformin and PPI use should also be reassessed regularly. In patients who require long-term metformin use, IM administration of B12 1000 mcg annually should be considered, which will ensure adequate storage for more than 1 year.^12,13 In patients who require long-term PPI use, the risk and benefits of continued use should be measured, and if needed, the lowest possible effective PPI dose is recommended.¹⁴ Irreversible causes of B12 deficiency, such as advanced age, prior gastrectomy, chronic pancreatitis, or autoimmune pernicious anemia, require lifelong supplementation of B12.^4,11

In general, oral vitamin B12 replacement at 1000 to 2000 mcg daily may be as effective as parenteral replacement in patients with mild to moderate deficiency or neurologic symptoms.¹¹ On the other hand, patients with SCD often require parenteral replacement of B12 due to the severity of their deficiency or neurologic symptoms, need for more rapid improvement in symptoms, and prevention of irreversible neurological deficits. ^4,11 Appropriate B12 replacement in SCD requires intensive initial therapy which may involve IM B12 1000 mcg every other day for 2 weeks and additional IM supplementation every 2 to 3 months afterward until resolution of deficiency.^4,14 IM replacement may also be considered in patients who are nonadherent to oral replacement or have an underlying gastrointestinal condition that impairs enteral absorption.^4,11

B12 deficiency is frequently undertreated and can lead to progression of disease with significant morbidity. The need for highintensity dosing of B12 replacement is crucial in patients with SCD. Failure to respond to treatment, as shown from the lack of improvement of serum markers or symptoms, likely suggests undertreatment, treatment nonadherence, iron deficiency anemia, an unidentified malabsorption syndrome, or other diagnoses. In our case, significant undertreatment, compounded by his suspected iron deficiency anemia secondary to his polycythemia vera and chronic phlebotomies, are the most likel etiologies for his lack of clinical improvement.

Multiple factors may affect the prognosis of SCD. Males aged < 50 years with absence of anemia, spinal cord atrophy, Romberg sign, Babinski sign, or sensory deficits on examination have increased likelihood of eventual recovery of signs and symptoms of SCD; those with less spinal cord involvement (< 7 cord segments), contrast enhancement, and spinal cord edema also have improved outcomes.^4,15

Conclusion

SCD is a rare but serious complication of chronic vitamin B12 deficiency that presents with a variety of neurological findings and may be easily confused with other illnesses. The condition is easily overlooked or misdiagnosed; thus, it is crucial to differentiate B12 deficiency from other common causes of neurologic symptoms. Specific findings on MRI are useful to support the clinical diagnosis of SCD and guide clinical decisions. Given the prevalence of B12 deficiency in the older adult population, clinicians should remain alert to the possibility of these conditions in patients who present with progressive neuropathy. Once a patient is diagnosed with SCD secondary to a B12 deficiency, appropriate B12 replacement is critical. Appropriate B12 replacement is aggressive and involves IM B12 1000 mcg every other day for 2 to 3 weeks, followed by additional IM administration every 2 months before transitioning to oral therapy. As seen in this case, failure to adequately replenish B12 can lead to progression or lack of resolution of SCD symptoms.

The COVID-19 pandemic has resulted in notable morbidity and mortality worldwide. In December 2020, the US Food and Drug Administration issued an Emergency Use Authorization for 2 messenger RNA (mRNA) vaccines—produced by Pfizer-BioNTech and Moderna—for the prevention of COVID-19. Phase 3 trials of the vaccine developed by Moderna showed 94.1% efficacy at preventing COVID-19 after 2 doses.¹

Common cutaneous adverse effects of the Moderna COVID-19 Vaccine include injection-site reactions, such as pain, induration, and erythema. Less frequently reported dermatologic adverse effects include diffuse bullous rash and hypersensitivity reactions.¹ We report a case of reactivation of a BCG vaccination scar after the first dose of the Moderna COVID-19 Vaccine.

Case Report

A 48-year-old Asian man who was otherwise healthy presented with erythema, induration, and mild pruritus on the deltoid muscle of the left arm, near the scar from an earlier BCG vaccine, which he received at approximately 5 years of age when living in Taiwan. The patient received the first dose of the Moderna COVID-19 Vaccine approximately 5 to 7 cm distant from the BCG vaccination scar. One to 2 days after inoculation, the patient endorsed tenderness at the site of COVID-19 vaccination but denied systemic symptoms. He had never been given a diagnosis of COVID-19. His SARS-CoV-2 antibody status was unknown.

Eight days later, the patient noticed a well-defined, erythematous, indurated plaque with mild itchiness overlying and around the BCG vaccination scar that did not involve the COVID-19 vaccination site. The following day, the redness and induration became worse (Figure).

The patient was otherwise well. Vital signs were normal; there was no lymphadenopathy. The rash resolved without treatment over the next 4 days.

Comment

The BCG vaccine is an intradermal live attenuated virus vaccine used to prevent certain forms of tuberculosis and potentially other Mycobacterium infections. Although the vaccine is not routinely administered in the United States, it is part of the vaccination schedule in most countries, administered most often to newborns and infants. Administration of the BCG vaccine commonly results in mild localized erythema, swelling, and pain at the injection site. Most inoculated patients also develop an ulcer that heals with the characteristic BCG vaccination scar.^2,3

There is evidence that the BCG vaccine can enhance the innate immune system response and might decrease the rate of infection by unrelated pathogens, including viruses.⁴ Several epidemiologic studies have suggested that the BCG vaccine might offer some protection against COVID-19, possibly due to a resemblance of the amino acid sequences of BCG and SARS-CoV-2, which might provoke cross-reactive T cells.^5,6 Further studies are underway to determine whether the BCG vaccine is truly protective against COVID-19.

BCG vaccination scar reactivation presents as redness, swelling, or ulceration at the BCG injection site months to years after inoculation. Although erythema and induration of the BCG scar are not included in the diagnostic criteria of Kawasaki disease, likely due to variable vaccine requirements in different countries, these findings are largely recognized as specific for Kawasaki disease and present in approximately half of affected patients who received the BCG vaccine.²

Heat Shock Proteins—Heat shock proteins (HSPs) are produced by cells in response to stressors. The proposed mechanism of BCG vaccination scar reactivation is a cross-reaction between human homologue HSP 63 and Mycobacterium HSP 65, leading to hyperactivity of the immune system against BCG.⁷ There also are reports of reactivation of a BCG vaccination scar from measles infection and influenza vaccination.^2,8,9 Most prior reports of BCG vaccination scar reactivation have been in pediatric patients; our patient is an adult who received the BCG vaccine more than 40 years ago.

Mechanism of Reactivation—The mechanism of BCG vaccination scar reactivation in our patient, who received the Moderna COVID-19 Vaccine, is unclear. Possible mechanisms include (1) release of HSP mediated by the COVID-19 vaccine, leading to an immune response at the BCG vaccine scar, or (2) another immune-mediated cross-reaction between BCG and the Moderna COVID-19 Vaccine mRNA nanoparticle or encoded spike protein antigen. It has been hypothesized that the BCG vaccine might offer some protection against COVID-19; this remains uncertain and is under further investigation.¹⁰ A recent retrospective cohort study showed that a BCG vaccination booster may decrease COVID-19 infection rates in higher-risk populations.¹¹

Conclusion

We present a case of BCG vaccine scar reactivation occurring after a dose of the Moderna COVID-19 Vaccine, a likely underreported, self-limiting, cutaneous adverse effect of this mRNA vaccine.

The COVID-19 pandemic has resulted in notable morbidity and mortality worldwide. In December 2020, the US Food and Drug Administration issued an Emergency Use Authorization for 2 messenger RNA (mRNA) vaccines—produced by Pfizer-BioNTech and Moderna—for the prevention of COVID-19. Phase 3 trials of the vaccine developed by Moderna showed 94.1% efficacy at preventing COVID-19 after 2 doses.¹

Common cutaneous adverse effects of the Moderna COVID-19 Vaccine include injection-site reactions, such as pain, induration, and erythema. Less frequently reported dermatologic adverse effects include diffuse bullous rash and hypersensitivity reactions.¹ We report a case of reactivation of a BCG vaccination scar after the first dose of the Moderna COVID-19 Vaccine.

Case Report

A 48-year-old Asian man who was otherwise healthy presented with erythema, induration, and mild pruritus on the deltoid muscle of the left arm, near the scar from an earlier BCG vaccine, which he received at approximately 5 years of age when living in Taiwan. The patient received the first dose of the Moderna COVID-19 Vaccine approximately 5 to 7 cm distant from the BCG vaccination scar. One to 2 days after inoculation, the patient endorsed tenderness at the site of COVID-19 vaccination but denied systemic symptoms. He had never been given a diagnosis of COVID-19. His SARS-CoV-2 antibody status was unknown.

Eight days later, the patient noticed a well-defined, erythematous, indurated plaque with mild itchiness overlying and around the BCG vaccination scar that did not involve the COVID-19 vaccination site. The following day, the redness and induration became worse (Figure).

The patient was otherwise well. Vital signs were normal; there was no lymphadenopathy. The rash resolved without treatment over the next 4 days.

Comment

The BCG vaccine is an intradermal live attenuated virus vaccine used to prevent certain forms of tuberculosis and potentially other Mycobacterium infections. Although the vaccine is not routinely administered in the United States, it is part of the vaccination schedule in most countries, administered most often to newborns and infants. Administration of the BCG vaccine commonly results in mild localized erythema, swelling, and pain at the injection site. Most inoculated patients also develop an ulcer that heals with the characteristic BCG vaccination scar.^2,3

There is evidence that the BCG vaccine can enhance the innate immune system response and might decrease the rate of infection by unrelated pathogens, including viruses.⁴ Several epidemiologic studies have suggested that the BCG vaccine might offer some protection against COVID-19, possibly due to a resemblance of the amino acid sequences of BCG and SARS-CoV-2, which might provoke cross-reactive T cells.^5,6 Further studies are underway to determine whether the BCG vaccine is truly protective against COVID-19.

BCG vaccination scar reactivation presents as redness, swelling, or ulceration at the BCG injection site months to years after inoculation. Although erythema and induration of the BCG scar are not included in the diagnostic criteria of Kawasaki disease, likely due to variable vaccine requirements in different countries, these findings are largely recognized as specific for Kawasaki disease and present in approximately half of affected patients who received the BCG vaccine.²

Heat Shock Proteins—Heat shock proteins (HSPs) are produced by cells in response to stressors. The proposed mechanism of BCG vaccination scar reactivation is a cross-reaction between human homologue HSP 63 and Mycobacterium HSP 65, leading to hyperactivity of the immune system against BCG.⁷ There also are reports of reactivation of a BCG vaccination scar from measles infection and influenza vaccination.^2,8,9 Most prior reports of BCG vaccination scar reactivation have been in pediatric patients; our patient is an adult who received the BCG vaccine more than 40 years ago.

Mechanism of Reactivation—The mechanism of BCG vaccination scar reactivation in our patient, who received the Moderna COVID-19 Vaccine, is unclear. Possible mechanisms include (1) release of HSP mediated by the COVID-19 vaccine, leading to an immune response at the BCG vaccine scar, or (2) another immune-mediated cross-reaction between BCG and the Moderna COVID-19 Vaccine mRNA nanoparticle or encoded spike protein antigen. It has been hypothesized that the BCG vaccine might offer some protection against COVID-19; this remains uncertain and is under further investigation.¹⁰ A recent retrospective cohort study showed that a BCG vaccination booster may decrease COVID-19 infection rates in higher-risk populations.¹¹

Conclusion

We present a case of BCG vaccine scar reactivation occurring after a dose of the Moderna COVID-19 Vaccine, a likely underreported, self-limiting, cutaneous adverse effect of this mRNA vaccine.

The COVID-19 pandemic has resulted in notable morbidity and mortality worldwide. In December 2020, the US Food and Drug Administration issued an Emergency Use Authorization for 2 messenger RNA (mRNA) vaccines—produced by Pfizer-BioNTech and Moderna—for the prevention of COVID-19. Phase 3 trials of the vaccine developed by Moderna showed 94.1% efficacy at preventing COVID-19 after 2 doses.¹

Common cutaneous adverse effects of the Moderna COVID-19 Vaccine include injection-site reactions, such as pain, induration, and erythema. Less frequently reported dermatologic adverse effects include diffuse bullous rash and hypersensitivity reactions.¹ We report a case of reactivation of a BCG vaccination scar after the first dose of the Moderna COVID-19 Vaccine.

Case Report

A 48-year-old Asian man who was otherwise healthy presented with erythema, induration, and mild pruritus on the deltoid muscle of the left arm, near the scar from an earlier BCG vaccine, which he received at approximately 5 years of age when living in Taiwan. The patient received the first dose of the Moderna COVID-19 Vaccine approximately 5 to 7 cm distant from the BCG vaccination scar. One to 2 days after inoculation, the patient endorsed tenderness at the site of COVID-19 vaccination but denied systemic symptoms. He had never been given a diagnosis of COVID-19. His SARS-CoV-2 antibody status was unknown.

Eight days later, the patient noticed a well-defined, erythematous, indurated plaque with mild itchiness overlying and around the BCG vaccination scar that did not involve the COVID-19 vaccination site. The following day, the redness and induration became worse (Figure).

The patient was otherwise well. Vital signs were normal; there was no lymphadenopathy. The rash resolved without treatment over the next 4 days.

Comment

The BCG vaccine is an intradermal live attenuated virus vaccine used to prevent certain forms of tuberculosis and potentially other Mycobacterium infections. Although the vaccine is not routinely administered in the United States, it is part of the vaccination schedule in most countries, administered most often to newborns and infants. Administration of the BCG vaccine commonly results in mild localized erythema, swelling, and pain at the injection site. Most inoculated patients also develop an ulcer that heals with the characteristic BCG vaccination scar.^2,3

There is evidence that the BCG vaccine can enhance the innate immune system response and might decrease the rate of infection by unrelated pathogens, including viruses.⁴ Several epidemiologic studies have suggested that the BCG vaccine might offer some protection against COVID-19, possibly due to a resemblance of the amino acid sequences of BCG and SARS-CoV-2, which might provoke cross-reactive T cells.^5,6 Further studies are underway to determine whether the BCG vaccine is truly protective against COVID-19.

BCG vaccination scar reactivation presents as redness, swelling, or ulceration at the BCG injection site months to years after inoculation. Although erythema and induration of the BCG scar are not included in the diagnostic criteria of Kawasaki disease, likely due to variable vaccine requirements in different countries, these findings are largely recognized as specific for Kawasaki disease and present in approximately half of affected patients who received the BCG vaccine.²

Heat Shock Proteins—Heat shock proteins (HSPs) are produced by cells in response to stressors. The proposed mechanism of BCG vaccination scar reactivation is a cross-reaction between human homologue HSP 63 and Mycobacterium HSP 65, leading to hyperactivity of the immune system against BCG.⁷ There also are reports of reactivation of a BCG vaccination scar from measles infection and influenza vaccination.^2,8,9 Most prior reports of BCG vaccination scar reactivation have been in pediatric patients; our patient is an adult who received the BCG vaccine more than 40 years ago.

Mechanism of Reactivation—The mechanism of BCG vaccination scar reactivation in our patient, who received the Moderna COVID-19 Vaccine, is unclear. Possible mechanisms include (1) release of HSP mediated by the COVID-19 vaccine, leading to an immune response at the BCG vaccine scar, or (2) another immune-mediated cross-reaction between BCG and the Moderna COVID-19 Vaccine mRNA nanoparticle or encoded spike protein antigen. It has been hypothesized that the BCG vaccine might offer some protection against COVID-19; this remains uncertain and is under further investigation.¹⁰ A recent retrospective cohort study showed that a BCG vaccination booster may decrease COVID-19 infection rates in higher-risk populations.¹¹

Conclusion

We present a case of BCG vaccine scar reactivation occurring after a dose of the Moderna COVID-19 Vaccine, a likely underreported, self-limiting, cutaneous adverse effect of this mRNA vaccine.

THE CASE

A previously healthy 3-year-old girl presented to the emergency department with 4 days of fever and 2 days of right-side neck pain. The maximum temperature at home was 103 °F. The patient was irritable and vomited once. There were no other apparent or reported symptoms.

The neck exam was notable for nonfluctuant, swollen, and tender lymph nodes on the right side. Her sclera and conjunctiva were clear, and her oropharynx was unremarkable. Lab work revealed leukocytosis, with a white blood cell (WBC) count of 15.5 × 10³/µL (normal range, 4.0-10.0 × 10³/µL). She was given one 20 cc/kg normal saline bolus, started on intravenous clindamycin for presumed cervical lymphadenitis, and admitted to the hospital.

On Day 2, the patient developed a fine maculopapular rash on her chest, abdomen, and back. She had spiking fevers—as high as 102.2 °F—despite being on antibiotics for more than 24 hours. The erythrocyte sedimentation rate (ESR) was 39 mm/h (0-20 mm/h), and C-reactive protein (CRP) was 71.4 mg/L (0.0-4.9 mg/L). Due to concern for abscess, a neck ultrasound was performed; it showed a chain of enlarged lymph nodes in the right neck (largest, 2.3 × 1.1 × 1.4 cm) and no abscess.

On Day 3, clindamycin was switched to intravenous ampicillin/sulbactam because a nasal swab for methicillin-resistant Staphylococcus aureus was negative. A swab for respiratory viral infections was also negative. The patient then developed notable facial swelling, bilateral bulbar conjunctival injection with limbic sparing, and swelling of her hands and feet.

THE DIAGNOSIS

By the end of Day 3, the patient’s lab studies demonstrated microcytic anemia and low albumin (2.5 g/dL), but no transaminitis, thrombocytosis, or sterile pyuria. An electrocardiogram was unremarkable. A pediatric echocardiogram revealed hyperemic coronaries, indicating inflammation. The coronary arteries were measured in the upper limits of normal, and the patient’s Z-scores were < 2.5. (A Z-score < 2 indicates no involvement, 2 to < 2.5 indicates dilation, and ≥ 2.5 indicates aneurysm abnormality.¹) An ultrasound of the right upper quadrant revealed an enlarged/elongated gallbladder. The patient therefore met clinical criteria for Kawasaki disease.

DISCUSSION

Kawasaki disease is a self-limited vasculitis of childhood and the leading cause of acquired heart disease in children in developed countries.¹ The annual incidence of Kawasaki disease in North America is about 25 cases per 100,000 children < 5 years of age.¹ In the United States, incidence is highest in Asian and Pacific Islander populations (30 per 100,000) and is particularly high among those of Japanese ancestry (~200 per 100,000).² Disease prevalence is also noteworthy in Non-Hispanic African American (17 per 100,000) and Hispanic (16 per 100,000) populations.²

Diagnosis of Kawasaki disease requires presence of fever lasting at least 5 days and at least 4 of the following: bilateral bulbar conjunctival injection, oral mucous membrane changes (erythematous or cracked lips, erythematous pharynx, strawberry tongue), peripheral extremity changes (erythema of palms or soles, edema of hands or feet, and/or periungual desquamation), diffuse maculopapular rash, and cervical lymphadenopathy (≥ 1.5 cm, often unilateral). If ≥ 4 criteria are met, Kawasaki disease can be diagnosed on the fourth day of illness.¹

Continue to: Laboratory findings suggesting...

Laboratory findings suggesting ­Kawasaki disease include a WBC count ≥ 15,000/mcL, normocytic, normochromic anemia, platelets ≥ 450,000/mcL after 7 days of illness, sterile pyuria (≥ 10 WBCs/high-power field), serum alanine aminotransferase level > 50 U/L, and serum albumin ≤ 3 g/dL.

Cardiac abnormalities are not included in the diagnostic criteria for Kawasaki disease but provide evidence in cases of incomplete Kawasaki disease if ≥ 4 criteria are not met and there is strong clinical suspicion.¹ Incomplete Kawasaki disease should be considered in a patient with a CRP level ≥ 3 mg/dL and/or ESR ≥ 40 mm/h, ≥ 3 supplemental laboratory criteria, or a positive echocardiogram.¹

Ultrasound imaging may reveal cervical lymph nodes resembling a “cluster of grapes.”³ The case patient’s imaging showed a “chain of enlarged lymph nodes.” She likely had gallbladder “hydrops” due to its increased longitudinal and horizontal diameter and lack of other anatomic changes.⁴

Prompt treatment is essential

Treatment for complete and incomplete Kawasaki disease is a single high dose of intravenous immunoglobulin (IVIG) along with aspirin. Patients meeting criteria should be treated as soon as the diagnosis is established.⁵ A single high dose of IVIG (2 g/kg), administered over 10 to 12 hours, should be initiated within 5 to 10 days of disease onset. Administering IVIG in the acute phase of Kawasaki disease reduces the prevalence of coronary artery abnormalities.⁶ Corticosteroids may be used as adjunctive therapy for patients with high risk of IVIG resistance.^1,7-9

Our patient was not deemed to be at high risk for IVIG resistance (Non-Japanese patient, age at fever onset > 6 months, absence of coronary artery aneurysm⁹) and was administered IVIG on Day 4. She was also given moderate-dose aspirin, then later transitioned to low-dose aspirin. The patient’s fevers improved, she was less irritable, and she had periods of playfulness. Physical exam then showed erythematous and cracked lips with peeling skin.

Continue to: The patient was discharged...

Untreated children with Kawasaki disease have a 25% chance of developing coronary artery aneurysms.

The patient was discharged home on Day 8, after her fever resolved, with instructions to continue low-dose aspirin and to obtain a repeat echocardiogram, gallbladder ultrasound, and lab work in 2 weeks. At her follow-up appointment, periungual desquamation was noted, and ultrasound showed continued enlarged/elongated gallbladder. A repeat echocardiogram was not available. Overall, the patient recovered from Kawasaki disease after therapeutic intervention.

THE TAKEAWAY

Kawasaki disease can be relatively rare in North American populations, but it is important for physicians to be able to recognize and treat it. Untreated children have a 25% chance of developing coronary artery aneurysms.^1,10,11 Early treatment with IVIG can decrease risk to 5%, resulting in an excellent medium- to long-term prognosis for patients.¹⁰ Thorough physical examination and an appropriate degree of clinical suspicion was key in this case of Kawasaki disease.

CORRESPONDENCE
Taisha Doo, MD, 1401 Madison Street, Suite #100, Seattle, WA 98104; [email protected]

THE CASE

A previously healthy 3-year-old girl presented to the emergency department with 4 days of fever and 2 days of right-side neck pain. The maximum temperature at home was 103 °F. The patient was irritable and vomited once. There were no other apparent or reported symptoms.

The neck exam was notable for nonfluctuant, swollen, and tender lymph nodes on the right side. Her sclera and conjunctiva were clear, and her oropharynx was unremarkable. Lab work revealed leukocytosis, with a white blood cell (WBC) count of 15.5 × 10³/µL (normal range, 4.0-10.0 × 10³/µL). She was given one 20 cc/kg normal saline bolus, started on intravenous clindamycin for presumed cervical lymphadenitis, and admitted to the hospital.

On Day 2, the patient developed a fine maculopapular rash on her chest, abdomen, and back. She had spiking fevers—as high as 102.2 °F—despite being on antibiotics for more than 24 hours. The erythrocyte sedimentation rate (ESR) was 39 mm/h (0-20 mm/h), and C-reactive protein (CRP) was 71.4 mg/L (0.0-4.9 mg/L). Due to concern for abscess, a neck ultrasound was performed; it showed a chain of enlarged lymph nodes in the right neck (largest, 2.3 × 1.1 × 1.4 cm) and no abscess.

On Day 3, clindamycin was switched to intravenous ampicillin/sulbactam because a nasal swab for methicillin-resistant Staphylococcus aureus was negative. A swab for respiratory viral infections was also negative. The patient then developed notable facial swelling, bilateral bulbar conjunctival injection with limbic sparing, and swelling of her hands and feet.

THE DIAGNOSIS

By the end of Day 3, the patient’s lab studies demonstrated microcytic anemia and low albumin (2.5 g/dL), but no transaminitis, thrombocytosis, or sterile pyuria. An electrocardiogram was unremarkable. A pediatric echocardiogram revealed hyperemic coronaries, indicating inflammation. The coronary arteries were measured in the upper limits of normal, and the patient’s Z-scores were < 2.5. (A Z-score < 2 indicates no involvement, 2 to < 2.5 indicates dilation, and ≥ 2.5 indicates aneurysm abnormality.¹) An ultrasound of the right upper quadrant revealed an enlarged/elongated gallbladder. The patient therefore met clinical criteria for Kawasaki disease.

DISCUSSION

Kawasaki disease is a self-limited vasculitis of childhood and the leading cause of acquired heart disease in children in developed countries.¹ The annual incidence of Kawasaki disease in North America is about 25 cases per 100,000 children < 5 years of age.¹ In the United States, incidence is highest in Asian and Pacific Islander populations (30 per 100,000) and is particularly high among those of Japanese ancestry (~200 per 100,000).² Disease prevalence is also noteworthy in Non-Hispanic African American (17 per 100,000) and Hispanic (16 per 100,000) populations.²

Diagnosis of Kawasaki disease requires presence of fever lasting at least 5 days and at least 4 of the following: bilateral bulbar conjunctival injection, oral mucous membrane changes (erythematous or cracked lips, erythematous pharynx, strawberry tongue), peripheral extremity changes (erythema of palms or soles, edema of hands or feet, and/or periungual desquamation), diffuse maculopapular rash, and cervical lymphadenopathy (≥ 1.5 cm, often unilateral). If ≥ 4 criteria are met, Kawasaki disease can be diagnosed on the fourth day of illness.¹

Continue to: Laboratory findings suggesting...

Laboratory findings suggesting ­Kawasaki disease include a WBC count ≥ 15,000/mcL, normocytic, normochromic anemia, platelets ≥ 450,000/mcL after 7 days of illness, sterile pyuria (≥ 10 WBCs/high-power field), serum alanine aminotransferase level > 50 U/L, and serum albumin ≤ 3 g/dL.

Cardiac abnormalities are not included in the diagnostic criteria for Kawasaki disease but provide evidence in cases of incomplete Kawasaki disease if ≥ 4 criteria are not met and there is strong clinical suspicion.¹ Incomplete Kawasaki disease should be considered in a patient with a CRP level ≥ 3 mg/dL and/or ESR ≥ 40 mm/h, ≥ 3 supplemental laboratory criteria, or a positive echocardiogram.¹

Ultrasound imaging may reveal cervical lymph nodes resembling a “cluster of grapes.”³ The case patient’s imaging showed a “chain of enlarged lymph nodes.” She likely had gallbladder “hydrops” due to its increased longitudinal and horizontal diameter and lack of other anatomic changes.⁴

Prompt treatment is essential

Treatment for complete and incomplete Kawasaki disease is a single high dose of intravenous immunoglobulin (IVIG) along with aspirin. Patients meeting criteria should be treated as soon as the diagnosis is established.⁵ A single high dose of IVIG (2 g/kg), administered over 10 to 12 hours, should be initiated within 5 to 10 days of disease onset. Administering IVIG in the acute phase of Kawasaki disease reduces the prevalence of coronary artery abnormalities.⁶ Corticosteroids may be used as adjunctive therapy for patients with high risk of IVIG resistance.^1,7-9

Our patient was not deemed to be at high risk for IVIG resistance (Non-Japanese patient, age at fever onset > 6 months, absence of coronary artery aneurysm⁹) and was administered IVIG on Day 4. She was also given moderate-dose aspirin, then later transitioned to low-dose aspirin. The patient’s fevers improved, she was less irritable, and she had periods of playfulness. Physical exam then showed erythematous and cracked lips with peeling skin.

Continue to: The patient was discharged...

Untreated children with Kawasaki disease have a 25% chance of developing coronary artery aneurysms.

The patient was discharged home on Day 8, after her fever resolved, with instructions to continue low-dose aspirin and to obtain a repeat echocardiogram, gallbladder ultrasound, and lab work in 2 weeks. At her follow-up appointment, periungual desquamation was noted, and ultrasound showed continued enlarged/elongated gallbladder. A repeat echocardiogram was not available. Overall, the patient recovered from Kawasaki disease after therapeutic intervention.

THE TAKEAWAY

Kawasaki disease can be relatively rare in North American populations, but it is important for physicians to be able to recognize and treat it. Untreated children have a 25% chance of developing coronary artery aneurysms.^1,10,11 Early treatment with IVIG can decrease risk to 5%, resulting in an excellent medium- to long-term prognosis for patients.¹⁰ Thorough physical examination and an appropriate degree of clinical suspicion was key in this case of Kawasaki disease.

CORRESPONDENCE
Taisha Doo, MD, 1401 Madison Street, Suite #100, Seattle, WA 98104; [email protected]

THE CASE

A previously healthy 3-year-old girl presented to the emergency department with 4 days of fever and 2 days of right-side neck pain. The maximum temperature at home was 103 °F. The patient was irritable and vomited once. There were no other apparent or reported symptoms.

The neck exam was notable for nonfluctuant, swollen, and tender lymph nodes on the right side. Her sclera and conjunctiva were clear, and her oropharynx was unremarkable. Lab work revealed leukocytosis, with a white blood cell (WBC) count of 15.5 × 10³/µL (normal range, 4.0-10.0 × 10³/µL). She was given one 20 cc/kg normal saline bolus, started on intravenous clindamycin for presumed cervical lymphadenitis, and admitted to the hospital.

On Day 2, the patient developed a fine maculopapular rash on her chest, abdomen, and back. She had spiking fevers—as high as 102.2 °F—despite being on antibiotics for more than 24 hours. The erythrocyte sedimentation rate (ESR) was 39 mm/h (0-20 mm/h), and C-reactive protein (CRP) was 71.4 mg/L (0.0-4.9 mg/L). Due to concern for abscess, a neck ultrasound was performed; it showed a chain of enlarged lymph nodes in the right neck (largest, 2.3 × 1.1 × 1.4 cm) and no abscess.

On Day 3, clindamycin was switched to intravenous ampicillin/sulbactam because a nasal swab for methicillin-resistant Staphylococcus aureus was negative. A swab for respiratory viral infections was also negative. The patient then developed notable facial swelling, bilateral bulbar conjunctival injection with limbic sparing, and swelling of her hands and feet.

THE DIAGNOSIS

By the end of Day 3, the patient’s lab studies demonstrated microcytic anemia and low albumin (2.5 g/dL), but no transaminitis, thrombocytosis, or sterile pyuria. An electrocardiogram was unremarkable. A pediatric echocardiogram revealed hyperemic coronaries, indicating inflammation. The coronary arteries were measured in the upper limits of normal, and the patient’s Z-scores were < 2.5. (A Z-score < 2 indicates no involvement, 2 to < 2.5 indicates dilation, and ≥ 2.5 indicates aneurysm abnormality.¹) An ultrasound of the right upper quadrant revealed an enlarged/elongated gallbladder. The patient therefore met clinical criteria for Kawasaki disease.

DISCUSSION

Kawasaki disease is a self-limited vasculitis of childhood and the leading cause of acquired heart disease in children in developed countries.¹ The annual incidence of Kawasaki disease in North America is about 25 cases per 100,000 children < 5 years of age.¹ In the United States, incidence is highest in Asian and Pacific Islander populations (30 per 100,000) and is particularly high among those of Japanese ancestry (~200 per 100,000).² Disease prevalence is also noteworthy in Non-Hispanic African American (17 per 100,000) and Hispanic (16 per 100,000) populations.²

Diagnosis of Kawasaki disease requires presence of fever lasting at least 5 days and at least 4 of the following: bilateral bulbar conjunctival injection, oral mucous membrane changes (erythematous or cracked lips, erythematous pharynx, strawberry tongue), peripheral extremity changes (erythema of palms or soles, edema of hands or feet, and/or periungual desquamation), diffuse maculopapular rash, and cervical lymphadenopathy (≥ 1.5 cm, often unilateral). If ≥ 4 criteria are met, Kawasaki disease can be diagnosed on the fourth day of illness.¹

Continue to: Laboratory findings suggesting...

Laboratory findings suggesting ­Kawasaki disease include a WBC count ≥ 15,000/mcL, normocytic, normochromic anemia, platelets ≥ 450,000/mcL after 7 days of illness, sterile pyuria (≥ 10 WBCs/high-power field), serum alanine aminotransferase level > 50 U/L, and serum albumin ≤ 3 g/dL.

Cardiac abnormalities are not included in the diagnostic criteria for Kawasaki disease but provide evidence in cases of incomplete Kawasaki disease if ≥ 4 criteria are not met and there is strong clinical suspicion.¹ Incomplete Kawasaki disease should be considered in a patient with a CRP level ≥ 3 mg/dL and/or ESR ≥ 40 mm/h, ≥ 3 supplemental laboratory criteria, or a positive echocardiogram.¹

Ultrasound imaging may reveal cervical lymph nodes resembling a “cluster of grapes.”³ The case patient’s imaging showed a “chain of enlarged lymph nodes.” She likely had gallbladder “hydrops” due to its increased longitudinal and horizontal diameter and lack of other anatomic changes.⁴

Prompt treatment is essential

Treatment for complete and incomplete Kawasaki disease is a single high dose of intravenous immunoglobulin (IVIG) along with aspirin. Patients meeting criteria should be treated as soon as the diagnosis is established.⁵ A single high dose of IVIG (2 g/kg), administered over 10 to 12 hours, should be initiated within 5 to 10 days of disease onset. Administering IVIG in the acute phase of Kawasaki disease reduces the prevalence of coronary artery abnormalities.⁶ Corticosteroids may be used as adjunctive therapy for patients with high risk of IVIG resistance.^1,7-9

Our patient was not deemed to be at high risk for IVIG resistance (Non-Japanese patient, age at fever onset > 6 months, absence of coronary artery aneurysm⁹) and was administered IVIG on Day 4. She was also given moderate-dose aspirin, then later transitioned to low-dose aspirin. The patient’s fevers improved, she was less irritable, and she had periods of playfulness. Physical exam then showed erythematous and cracked lips with peeling skin.

Continue to: The patient was discharged...

Untreated children with Kawasaki disease have a 25% chance of developing coronary artery aneurysms.

The patient was discharged home on Day 8, after her fever resolved, with instructions to continue low-dose aspirin and to obtain a repeat echocardiogram, gallbladder ultrasound, and lab work in 2 weeks. At her follow-up appointment, periungual desquamation was noted, and ultrasound showed continued enlarged/elongated gallbladder. A repeat echocardiogram was not available. Overall, the patient recovered from Kawasaki disease after therapeutic intervention.

THE TAKEAWAY

Kawasaki disease can be relatively rare in North American populations, but it is important for physicians to be able to recognize and treat it. Untreated children have a 25% chance of developing coronary artery aneurysms.^1,10,11 Early treatment with IVIG can decrease risk to 5%, resulting in an excellent medium- to long-term prognosis for patients.¹⁰ Thorough physical examination and an appropriate degree of clinical suspicion was key in this case of Kawasaki disease.

CORRESPONDENCE
Taisha Doo, MD, 1401 Madison Street, Suite #100, Seattle, WA 98104; [email protected]