Shari R. Lipner, MD, PhD

Practice Gap

The term nail biopsy (NB) may refer to a punch, excisional, shave, or longitudinal biopsy of the nail matrix and/or nail bed.¹ Nail surgeries, including NBs, are performed relatively infrequently. In a study using data from the Medicare Provider Utilization and Payment Database 2012-2017, only 1.01% of Mohs surgeons and 0.28% of general dermatologists in the United States performed NBs. Thirty-one states had no dermatologist-performed NBs, while 3 states had no nail biopsies performed by any physician, podiatrist, nurse practitioner, or physician assistant, indicating that there is a shortage of dermatology clinicians performing nail surgeries.²

Dermatologists may not be performing NBs due to unfamiliarity with nail unit anatomy and lack of formal NB training during residency.³ In a survey of 240 dermatology residents in the United States, 58% reported performing fewer than 10 nail procedures during residency, with 25% observing only.⁴ Of those surveyed, 1% had no exposure to nail procedures during 3 years of residency. Furthermore, when asked to assess their competency in nail surgery on a scale of not competent, competent, and very competent, approximately 30% responded that they were not competent.⁴ Without sufficient education on procedures involving the nail unit, residents may be reluctant to incorporate nail surgery into their clinical practice.

Due to their complexity, NBs require the use of several specialized surgical instruments that are not used for other dermatologic procedures, and residents and attending physicians who have limited nail training may be unfamiliar with these tools. To address this educational gap, we sought to create a guide that details the surgical instruments used for the nail matrix tangential excision (shave) biopsy technique—the most common technique used in our nail specialty clinic. This guide is intended for educational use by dermatologists who wish to incorporate NB as part of their practice.

Tools and Technique

As a major referral center, our New York City–based nail specialty clinic performs a large volume of NBs, many of them performed for clinically concerning longitudinal melanonychias for which a nail matrix shave biopsy most often is performed. We utilize a standardized tray consisting of 12 surgical instruments that are needed to successfully perform a NB from start to finish (Figure). In addition to standard surgical tray items, such as sutures and tissue scissors, additional specialized instruments are necessary for NB procedures, including a nail elevator, an English nail splitter, and skin hook.

After the initial incisions are made at 45° angles to the proximal nail fold surrounding the longitudinal band, the nail elevator is used to separate the proximal nail plate from the underlying nail bed. The English nail splitter is used to create a transverse split separating the proximal from the distal nail plate, and the proximal nail plate then is retracted using a clamp. The skin hook is used to retract the proximal nail fold to expose the pigment in the nail matrix, which is biopsied using the #15 blade and sent for histopathology. The proximal nail fold and retracted nail plate then are put back in place, and absorbable sutures are used to repair the defect. In certain cases, a 3-mm punch biopsy may be used to sample the nail plate and/or the surrounding soft tissue.

Practice Implications

A guide to surgical tools used during NB procedures, including less commonly encountered tools such as a nail elevator and English nail splitter, helps to close the educational gap of NB procedures among dermatology trainees and attending physicians. In conjunction with practical training with cadavers and models, a guide to surgical tools can be reviewed by trainees before hands-on exposure to nail surgery in a clinical setting. By increasing awareness of the tools needed to complete the procedure from start to finish, dermatologists may feel more prepared and confident in their ability to perform NBs, ultimately allowing for more rapid diagnosis of nail malignancies.

Practice Gap

The term nail biopsy (NB) may refer to a punch, excisional, shave, or longitudinal biopsy of the nail matrix and/or nail bed.¹ Nail surgeries, including NBs, are performed relatively infrequently. In a study using data from the Medicare Provider Utilization and Payment Database 2012-2017, only 1.01% of Mohs surgeons and 0.28% of general dermatologists in the United States performed NBs. Thirty-one states had no dermatologist-performed NBs, while 3 states had no nail biopsies performed by any physician, podiatrist, nurse practitioner, or physician assistant, indicating that there is a shortage of dermatology clinicians performing nail surgeries.²

Dermatologists may not be performing NBs due to unfamiliarity with nail unit anatomy and lack of formal NB training during residency.³ In a survey of 240 dermatology residents in the United States, 58% reported performing fewer than 10 nail procedures during residency, with 25% observing only.⁴ Of those surveyed, 1% had no exposure to nail procedures during 3 years of residency. Furthermore, when asked to assess their competency in nail surgery on a scale of not competent, competent, and very competent, approximately 30% responded that they were not competent.⁴ Without sufficient education on procedures involving the nail unit, residents may be reluctant to incorporate nail surgery into their clinical practice.

Due to their complexity, NBs require the use of several specialized surgical instruments that are not used for other dermatologic procedures, and residents and attending physicians who have limited nail training may be unfamiliar with these tools. To address this educational gap, we sought to create a guide that details the surgical instruments used for the nail matrix tangential excision (shave) biopsy technique—the most common technique used in our nail specialty clinic. This guide is intended for educational use by dermatologists who wish to incorporate NB as part of their practice.

Tools and Technique

As a major referral center, our New York City–based nail specialty clinic performs a large volume of NBs, many of them performed for clinically concerning longitudinal melanonychias for which a nail matrix shave biopsy most often is performed. We utilize a standardized tray consisting of 12 surgical instruments that are needed to successfully perform a NB from start to finish (Figure). In addition to standard surgical tray items, such as sutures and tissue scissors, additional specialized instruments are necessary for NB procedures, including a nail elevator, an English nail splitter, and skin hook.

After the initial incisions are made at 45° angles to the proximal nail fold surrounding the longitudinal band, the nail elevator is used to separate the proximal nail plate from the underlying nail bed. The English nail splitter is used to create a transverse split separating the proximal from the distal nail plate, and the proximal nail plate then is retracted using a clamp. The skin hook is used to retract the proximal nail fold to expose the pigment in the nail matrix, which is biopsied using the #15 blade and sent for histopathology. The proximal nail fold and retracted nail plate then are put back in place, and absorbable sutures are used to repair the defect. In certain cases, a 3-mm punch biopsy may be used to sample the nail plate and/or the surrounding soft tissue.

Practice Implications

A guide to surgical tools used during NB procedures, including less commonly encountered tools such as a nail elevator and English nail splitter, helps to close the educational gap of NB procedures among dermatology trainees and attending physicians. In conjunction with practical training with cadavers and models, a guide to surgical tools can be reviewed by trainees before hands-on exposure to nail surgery in a clinical setting. By increasing awareness of the tools needed to complete the procedure from start to finish, dermatologists may feel more prepared and confident in their ability to perform NBs, ultimately allowing for more rapid diagnosis of nail malignancies.

Practice Gap

The term nail biopsy (NB) may refer to a punch, excisional, shave, or longitudinal biopsy of the nail matrix and/or nail bed.¹ Nail surgeries, including NBs, are performed relatively infrequently. In a study using data from the Medicare Provider Utilization and Payment Database 2012-2017, only 1.01% of Mohs surgeons and 0.28% of general dermatologists in the United States performed NBs. Thirty-one states had no dermatologist-performed NBs, while 3 states had no nail biopsies performed by any physician, podiatrist, nurse practitioner, or physician assistant, indicating that there is a shortage of dermatology clinicians performing nail surgeries.²

Dermatologists may not be performing NBs due to unfamiliarity with nail unit anatomy and lack of formal NB training during residency.³ In a survey of 240 dermatology residents in the United States, 58% reported performing fewer than 10 nail procedures during residency, with 25% observing only.⁴ Of those surveyed, 1% had no exposure to nail procedures during 3 years of residency. Furthermore, when asked to assess their competency in nail surgery on a scale of not competent, competent, and very competent, approximately 30% responded that they were not competent.⁴ Without sufficient education on procedures involving the nail unit, residents may be reluctant to incorporate nail surgery into their clinical practice.

Due to their complexity, NBs require the use of several specialized surgical instruments that are not used for other dermatologic procedures, and residents and attending physicians who have limited nail training may be unfamiliar with these tools. To address this educational gap, we sought to create a guide that details the surgical instruments used for the nail matrix tangential excision (shave) biopsy technique—the most common technique used in our nail specialty clinic. This guide is intended for educational use by dermatologists who wish to incorporate NB as part of their practice.

Tools and Technique

As a major referral center, our New York City–based nail specialty clinic performs a large volume of NBs, many of them performed for clinically concerning longitudinal melanonychias for which a nail matrix shave biopsy most often is performed. We utilize a standardized tray consisting of 12 surgical instruments that are needed to successfully perform a NB from start to finish (Figure). In addition to standard surgical tray items, such as sutures and tissue scissors, additional specialized instruments are necessary for NB procedures, including a nail elevator, an English nail splitter, and skin hook.

After the initial incisions are made at 45° angles to the proximal nail fold surrounding the longitudinal band, the nail elevator is used to separate the proximal nail plate from the underlying nail bed. The English nail splitter is used to create a transverse split separating the proximal from the distal nail plate, and the proximal nail plate then is retracted using a clamp. The skin hook is used to retract the proximal nail fold to expose the pigment in the nail matrix, which is biopsied using the #15 blade and sent for histopathology. The proximal nail fold and retracted nail plate then are put back in place, and absorbable sutures are used to repair the defect. In certain cases, a 3-mm punch biopsy may be used to sample the nail plate and/or the surrounding soft tissue.

Practice Implications

A guide to surgical tools used during NB procedures, including less commonly encountered tools such as a nail elevator and English nail splitter, helps to close the educational gap of NB procedures among dermatology trainees and attending physicians. In conjunction with practical training with cadavers and models, a guide to surgical tools can be reviewed by trainees before hands-on exposure to nail surgery in a clinical setting. By increasing awareness of the tools needed to complete the procedure from start to finish, dermatologists may feel more prepared and confident in their ability to perform NBs, ultimately allowing for more rapid diagnosis of nail malignancies.

To the Editor:

Melasma (also known as chloasma) is characterized by symmetric hyperpigmented patches affecting sun-exposed areas. Women commonly develop this condition during pregnancy, suggesting a connection between melasma and increased female sex hormone levels.¹ Other hypothesized risk factors include sun exposure, genetic susceptibility, estrogen and/or progesterone therapy, and thyroid abnormalities but have not been corroborated.² Treatment options are limited because the pathogenesis is poorly understood; thus, we aimed to analyze melasma risk factors using a national database with a nested case-control approach.

We conducted a matched case-control study using the Registered Tier dataset (version 7) from the National Institute of Health’s All of Us Research Program (https://allofus.nih.gov/), which is available to authorized users through the program’s Researcher Workbench and includes more than 413,000 total participants enrolled from May 1, 2018, through July 1, 2022. Cases included patients 18 years and older with a diagnosis of melasma (International Classification of Diseases, Tenth Revision, Clinical Modification code L81.1 [Chloasma]; concept ID 4264234 [Chloasma]; and Systematized Nomenclature of Medicine [SNOMED] code 36209000 [Chloasma]), and controls without a diagnosis of melasma were matched in a 1:10 ratio based on age, sex, and self-reported race. Concept IDs and SNOMED codes were used to identify individuals in each cohort with a diagnosis of alcohol dependence (concept IDs 433753, 435243, 4218106; SNOMED codes 15167005, 66590003, 7200002), depression (concept ID 440383; SNOMED code 35489007), hypothyroidism (concept ID 140673; SNOMED code 40930008), hyperthyroidism (concept ID 4142479; SNOMED code 34486009), anxiety (concept IDs 441542, 442077, 434613; SNOMED codes 48694002, 197480006, 21897009), tobacco dependence (concept IDs 37109023, 437264, 4099811; SNOMED codes 16077091000119107, 89765005, 191887008), or obesity (concept IDs 433736 and 434005; SNOMED codes 414916001 and 238136002), or with a history of radiation therapy (concept IDs 4085340, 4311117, 4061844, 4029715; SNOMED codes 24803000, 85983004, 200861004, 108290001) or hormonal medications containing estrogen and/or progesterone, including oral medications and implants (concept IDs 21602445, 40254009, 21602514, 21603814, 19049228, 21602529, 1549080, 1551673, 1549254, 21602472, 21602446, 21602450, 21602515, 21602566, 21602473, 21602567, 21602488, 21602585, 1596779, 1586808, 21602524). In our case cohort, diagnoses and exposures to treatments were only considered for analysis if they occurred prior to melasma diagnosis.

Multivariate logistic regression was performed to calculate odds ratios and P values between melasma and each comorbidity or exposure to the treatments specified. Statistical significance was set at P<.05.

We identified 744 melasma cases (mean age, 55.20 years; 95.43% female; 12.10% Black) and 7440 controls with similar demographics (ie, age, sex, race/ethnicity) between groups (all P>.05 [Table 1]). Patients with a melasma diagnosis were more likely to have a pre-existing diagnosis of depression (OR, 1.87; 95% CI, 1.51-2.31 [P<.001]) or hypothyroidism (OR, 1.31; 95% CI, 1.04-1.65 [P<.05]), or a history of radiation therapy (OR, 19.08; 95% CI, 10.20-35.69 [P<.001]) and/or estrogen and/or progesterone therapy (OR, 2.01; 95% CI, 1.69-2.40 [P<.001]) prior to melasma diagnosis. A diagnosis of anxiety prior to melasma diagnosis trended toward an association with melasma (P=.067). Pre-existing alcohol dependence, obesity, and hyperthyroidism were not associated with melasma (P=.98, P=.28, and P=.29, respectively). A diagnosis of tobacco dependence was associated with a decreased melasma risk (OR, 0.53, 95% CI, 0.37-0.76)[P<.001])(Table 2).

Our study results suggest that pre-existing depression was a risk factor for subsequent melasma diagnosis. Depression may exacerbate stress, leading to increased activation of the hypothalamic-pituitary-adrenal axis as well as increased levels of cortisol and adrenocorticotropic hormone, which subsequently act on melanocytes to increase melanogenesis.³ A retrospective study of 254 participants, including 127 with melasma, showed that increased melasma severity was associated with higher rates of depression (P=.002)²; however, the risk for melasma following a depression diagnosis has not been reported.

Our results also showed that hypothyroidism was associated with an increased risk for melasma. On a cellular level, hypothyroidism can cause systemic inflammation, potentailly leading to increased stress and melanogenesis via activation of the hypothalamic-pituitary-adrenal axis.⁴ These findings are similar to a systematic review and meta-analysis reporting increased thyroid-stimulating hormone, anti–thyroid peroxidase, and antithyroglobulin antibody levels associated with increased melasma risk (mean difference between cases and controls, 0.33 [95% CI, 0.18-0.47]; pooled association, P=.020; mean difference between cases and controls, 0.28 [95% CI, 0.01-0.55], respectively).⁵

Patients in our cohort who had a history of radiation therapy were 19 times more likely to develop melasma, similar to findings of a survey-based study of 421 breast cancer survivors in which 336 (79.81%) reported hyperpigmentation in irradiated areas.⁶ Patients in our cohort who had a history of estrogen and/or progesterone therapy were 2 times more likely to develop melasma, similar to a case-control study of 207 patients with melasma and 207 controls that showed combined oral contraceptives increased risk for melasma (OR, 1.23 [95% CI, 1.08-1.41; P<.01).³

Tobacco use is not a well-known protective factor against melasma. Prior studies have indicated that tobacco smoking activates melanocytes via the Wnt/β-Catenin pathway, leading to hyperpigmentation.⁷ Although exposure to cigarette smoke decreases angiogenesis and would more likely lead to hyperpigmentation, nicotine exposure has been shown to increase angiogenesis, which could lead to increased blood flow and partially explain the protection against melasma demonstrated in our cohort.⁸ Future studies are needed to explore this relationship.

Limitations of our study include lack of information about melasma severity and information about prior melasma treatment in our cohort as well as possible misdiagnosis reported in the dataset.

Our results demonstrated that pre-existing depression and hypothyroidism as well as a history of radiation or estrogen and/or progesterone therapies are potential risk factors for melasma. Therefore, we recommend that patients with melasma be screened for depression and thyroid dysfunction, and patients undergoing radiation therapy or starting estrogen and/or progesterone therapy should be counseled on their increased risk for melasma. Future studies are needed to determine whether treatment of comorbidities such as hypothyroidism and depression improve melasma severity. The decreased risk for melasma associated with tobacco use also requires further investigation.

Acknowledgments—The All of Us Research Program is supported by the National Institutes of Health, Office of the Director: Regional Medical Centers: 1 OT2 OD026549; 1 OT2 OD026554; 1 OT2 OD026557; 1 OT2 OD026556; 1 OT2 OD026550; 1 OT2 OD 026552; 1 OT2 OD026553; 1 OT2 OD026548; 1 OT2 OD026551; 1 OT2 OD026555; IAA #: AOD 16037; Federally Qualified Health Centers: HHSN 263201600085U; Data and Research Center: 5 U2C OD023196; Biobank: 1 U24 OD023121; The Participant Center: U24 OD023176; Participant Technology Systems Center: 1 U24 OD023163; Communications and Engagement: 3 OT2 OD023205; 3 OT2 OD023206; and Community Partners: 1 OT2 OD025277; 3 OT2 OD025315; 1 OT2 OD025337; 1 OT2 OD025276.

In addition, the All of Us Research Program would not be possible without the partnership of its participants, who we gratefully acknowledge for their contributions and without whom this research would not have been possible. We also thank the All of Us Research Program for making the participant data examined in this study available to us.

To the Editor:

Melasma (also known as chloasma) is characterized by symmetric hyperpigmented patches affecting sun-exposed areas. Women commonly develop this condition during pregnancy, suggesting a connection between melasma and increased female sex hormone levels.¹ Other hypothesized risk factors include sun exposure, genetic susceptibility, estrogen and/or progesterone therapy, and thyroid abnormalities but have not been corroborated.² Treatment options are limited because the pathogenesis is poorly understood; thus, we aimed to analyze melasma risk factors using a national database with a nested case-control approach.

We conducted a matched case-control study using the Registered Tier dataset (version 7) from the National Institute of Health’s All of Us Research Program (https://allofus.nih.gov/), which is available to authorized users through the program’s Researcher Workbench and includes more than 413,000 total participants enrolled from May 1, 2018, through July 1, 2022. Cases included patients 18 years and older with a diagnosis of melasma (International Classification of Diseases, Tenth Revision, Clinical Modification code L81.1 [Chloasma]; concept ID 4264234 [Chloasma]; and Systematized Nomenclature of Medicine [SNOMED] code 36209000 [Chloasma]), and controls without a diagnosis of melasma were matched in a 1:10 ratio based on age, sex, and self-reported race. Concept IDs and SNOMED codes were used to identify individuals in each cohort with a diagnosis of alcohol dependence (concept IDs 433753, 435243, 4218106; SNOMED codes 15167005, 66590003, 7200002), depression (concept ID 440383; SNOMED code 35489007), hypothyroidism (concept ID 140673; SNOMED code 40930008), hyperthyroidism (concept ID 4142479; SNOMED code 34486009), anxiety (concept IDs 441542, 442077, 434613; SNOMED codes 48694002, 197480006, 21897009), tobacco dependence (concept IDs 37109023, 437264, 4099811; SNOMED codes 16077091000119107, 89765005, 191887008), or obesity (concept IDs 433736 and 434005; SNOMED codes 414916001 and 238136002), or with a history of radiation therapy (concept IDs 4085340, 4311117, 4061844, 4029715; SNOMED codes 24803000, 85983004, 200861004, 108290001) or hormonal medications containing estrogen and/or progesterone, including oral medications and implants (concept IDs 21602445, 40254009, 21602514, 21603814, 19049228, 21602529, 1549080, 1551673, 1549254, 21602472, 21602446, 21602450, 21602515, 21602566, 21602473, 21602567, 21602488, 21602585, 1596779, 1586808, 21602524). In our case cohort, diagnoses and exposures to treatments were only considered for analysis if they occurred prior to melasma diagnosis.

Multivariate logistic regression was performed to calculate odds ratios and P values between melasma and each comorbidity or exposure to the treatments specified. Statistical significance was set at P<.05.

We identified 744 melasma cases (mean age, 55.20 years; 95.43% female; 12.10% Black) and 7440 controls with similar demographics (ie, age, sex, race/ethnicity) between groups (all P>.05 [Table 1]). Patients with a melasma diagnosis were more likely to have a pre-existing diagnosis of depression (OR, 1.87; 95% CI, 1.51-2.31 [P<.001]) or hypothyroidism (OR, 1.31; 95% CI, 1.04-1.65 [P<.05]), or a history of radiation therapy (OR, 19.08; 95% CI, 10.20-35.69 [P<.001]) and/or estrogen and/or progesterone therapy (OR, 2.01; 95% CI, 1.69-2.40 [P<.001]) prior to melasma diagnosis. A diagnosis of anxiety prior to melasma diagnosis trended toward an association with melasma (P=.067). Pre-existing alcohol dependence, obesity, and hyperthyroidism were not associated with melasma (P=.98, P=.28, and P=.29, respectively). A diagnosis of tobacco dependence was associated with a decreased melasma risk (OR, 0.53, 95% CI, 0.37-0.76)[P<.001])(Table 2).

Our study results suggest that pre-existing depression was a risk factor for subsequent melasma diagnosis. Depression may exacerbate stress, leading to increased activation of the hypothalamic-pituitary-adrenal axis as well as increased levels of cortisol and adrenocorticotropic hormone, which subsequently act on melanocytes to increase melanogenesis.³ A retrospective study of 254 participants, including 127 with melasma, showed that increased melasma severity was associated with higher rates of depression (P=.002)²; however, the risk for melasma following a depression diagnosis has not been reported.

Our results also showed that hypothyroidism was associated with an increased risk for melasma. On a cellular level, hypothyroidism can cause systemic inflammation, potentailly leading to increased stress and melanogenesis via activation of the hypothalamic-pituitary-adrenal axis.⁴ These findings are similar to a systematic review and meta-analysis reporting increased thyroid-stimulating hormone, anti–thyroid peroxidase, and antithyroglobulin antibody levels associated with increased melasma risk (mean difference between cases and controls, 0.33 [95% CI, 0.18-0.47]; pooled association, P=.020; mean difference between cases and controls, 0.28 [95% CI, 0.01-0.55], respectively).⁵

Patients in our cohort who had a history of radiation therapy were 19 times more likely to develop melasma, similar to findings of a survey-based study of 421 breast cancer survivors in which 336 (79.81%) reported hyperpigmentation in irradiated areas.⁶ Patients in our cohort who had a history of estrogen and/or progesterone therapy were 2 times more likely to develop melasma, similar to a case-control study of 207 patients with melasma and 207 controls that showed combined oral contraceptives increased risk for melasma (OR, 1.23 [95% CI, 1.08-1.41; P<.01).³

Tobacco use is not a well-known protective factor against melasma. Prior studies have indicated that tobacco smoking activates melanocytes via the Wnt/β-Catenin pathway, leading to hyperpigmentation.⁷ Although exposure to cigarette smoke decreases angiogenesis and would more likely lead to hyperpigmentation, nicotine exposure has been shown to increase angiogenesis, which could lead to increased blood flow and partially explain the protection against melasma demonstrated in our cohort.⁸ Future studies are needed to explore this relationship.

Limitations of our study include lack of information about melasma severity and information about prior melasma treatment in our cohort as well as possible misdiagnosis reported in the dataset.

Our results demonstrated that pre-existing depression and hypothyroidism as well as a history of radiation or estrogen and/or progesterone therapies are potential risk factors for melasma. Therefore, we recommend that patients with melasma be screened for depression and thyroid dysfunction, and patients undergoing radiation therapy or starting estrogen and/or progesterone therapy should be counseled on their increased risk for melasma. Future studies are needed to determine whether treatment of comorbidities such as hypothyroidism and depression improve melasma severity. The decreased risk for melasma associated with tobacco use also requires further investigation.

Acknowledgments—The All of Us Research Program is supported by the National Institutes of Health, Office of the Director: Regional Medical Centers: 1 OT2 OD026549; 1 OT2 OD026554; 1 OT2 OD026557; 1 OT2 OD026556; 1 OT2 OD026550; 1 OT2 OD 026552; 1 OT2 OD026553; 1 OT2 OD026548; 1 OT2 OD026551; 1 OT2 OD026555; IAA #: AOD 16037; Federally Qualified Health Centers: HHSN 263201600085U; Data and Research Center: 5 U2C OD023196; Biobank: 1 U24 OD023121; The Participant Center: U24 OD023176; Participant Technology Systems Center: 1 U24 OD023163; Communications and Engagement: 3 OT2 OD023205; 3 OT2 OD023206; and Community Partners: 1 OT2 OD025277; 3 OT2 OD025315; 1 OT2 OD025337; 1 OT2 OD025276.

In addition, the All of Us Research Program would not be possible without the partnership of its participants, who we gratefully acknowledge for their contributions and without whom this research would not have been possible. We also thank the All of Us Research Program for making the participant data examined in this study available to us.

To the Editor:

Melasma (also known as chloasma) is characterized by symmetric hyperpigmented patches affecting sun-exposed areas. Women commonly develop this condition during pregnancy, suggesting a connection between melasma and increased female sex hormone levels.¹ Other hypothesized risk factors include sun exposure, genetic susceptibility, estrogen and/or progesterone therapy, and thyroid abnormalities but have not been corroborated.² Treatment options are limited because the pathogenesis is poorly understood; thus, we aimed to analyze melasma risk factors using a national database with a nested case-control approach.

We conducted a matched case-control study using the Registered Tier dataset (version 7) from the National Institute of Health’s All of Us Research Program (https://allofus.nih.gov/), which is available to authorized users through the program’s Researcher Workbench and includes more than 413,000 total participants enrolled from May 1, 2018, through July 1, 2022. Cases included patients 18 years and older with a diagnosis of melasma (International Classification of Diseases, Tenth Revision, Clinical Modification code L81.1 [Chloasma]; concept ID 4264234 [Chloasma]; and Systematized Nomenclature of Medicine [SNOMED] code 36209000 [Chloasma]), and controls without a diagnosis of melasma were matched in a 1:10 ratio based on age, sex, and self-reported race. Concept IDs and SNOMED codes were used to identify individuals in each cohort with a diagnosis of alcohol dependence (concept IDs 433753, 435243, 4218106; SNOMED codes 15167005, 66590003, 7200002), depression (concept ID 440383; SNOMED code 35489007), hypothyroidism (concept ID 140673; SNOMED code 40930008), hyperthyroidism (concept ID 4142479; SNOMED code 34486009), anxiety (concept IDs 441542, 442077, 434613; SNOMED codes 48694002, 197480006, 21897009), tobacco dependence (concept IDs 37109023, 437264, 4099811; SNOMED codes 16077091000119107, 89765005, 191887008), or obesity (concept IDs 433736 and 434005; SNOMED codes 414916001 and 238136002), or with a history of radiation therapy (concept IDs 4085340, 4311117, 4061844, 4029715; SNOMED codes 24803000, 85983004, 200861004, 108290001) or hormonal medications containing estrogen and/or progesterone, including oral medications and implants (concept IDs 21602445, 40254009, 21602514, 21603814, 19049228, 21602529, 1549080, 1551673, 1549254, 21602472, 21602446, 21602450, 21602515, 21602566, 21602473, 21602567, 21602488, 21602585, 1596779, 1586808, 21602524). In our case cohort, diagnoses and exposures to treatments were only considered for analysis if they occurred prior to melasma diagnosis.

Multivariate logistic regression was performed to calculate odds ratios and P values between melasma and each comorbidity or exposure to the treatments specified. Statistical significance was set at P<.05.

We identified 744 melasma cases (mean age, 55.20 years; 95.43% female; 12.10% Black) and 7440 controls with similar demographics (ie, age, sex, race/ethnicity) between groups (all P>.05 [Table 1]). Patients with a melasma diagnosis were more likely to have a pre-existing diagnosis of depression (OR, 1.87; 95% CI, 1.51-2.31 [P<.001]) or hypothyroidism (OR, 1.31; 95% CI, 1.04-1.65 [P<.05]), or a history of radiation therapy (OR, 19.08; 95% CI, 10.20-35.69 [P<.001]) and/or estrogen and/or progesterone therapy (OR, 2.01; 95% CI, 1.69-2.40 [P<.001]) prior to melasma diagnosis. A diagnosis of anxiety prior to melasma diagnosis trended toward an association with melasma (P=.067). Pre-existing alcohol dependence, obesity, and hyperthyroidism were not associated with melasma (P=.98, P=.28, and P=.29, respectively). A diagnosis of tobacco dependence was associated with a decreased melasma risk (OR, 0.53, 95% CI, 0.37-0.76)[P<.001])(Table 2).

Our study results suggest that pre-existing depression was a risk factor for subsequent melasma diagnosis. Depression may exacerbate stress, leading to increased activation of the hypothalamic-pituitary-adrenal axis as well as increased levels of cortisol and adrenocorticotropic hormone, which subsequently act on melanocytes to increase melanogenesis.³ A retrospective study of 254 participants, including 127 with melasma, showed that increased melasma severity was associated with higher rates of depression (P=.002)²; however, the risk for melasma following a depression diagnosis has not been reported.

Our results also showed that hypothyroidism was associated with an increased risk for melasma. On a cellular level, hypothyroidism can cause systemic inflammation, potentailly leading to increased stress and melanogenesis via activation of the hypothalamic-pituitary-adrenal axis.⁴ These findings are similar to a systematic review and meta-analysis reporting increased thyroid-stimulating hormone, anti–thyroid peroxidase, and antithyroglobulin antibody levels associated with increased melasma risk (mean difference between cases and controls, 0.33 [95% CI, 0.18-0.47]; pooled association, P=.020; mean difference between cases and controls, 0.28 [95% CI, 0.01-0.55], respectively).⁵

Patients in our cohort who had a history of radiation therapy were 19 times more likely to develop melasma, similar to findings of a survey-based study of 421 breast cancer survivors in which 336 (79.81%) reported hyperpigmentation in irradiated areas.⁶ Patients in our cohort who had a history of estrogen and/or progesterone therapy were 2 times more likely to develop melasma, similar to a case-control study of 207 patients with melasma and 207 controls that showed combined oral contraceptives increased risk for melasma (OR, 1.23 [95% CI, 1.08-1.41; P<.01).³

Tobacco use is not a well-known protective factor against melasma. Prior studies have indicated that tobacco smoking activates melanocytes via the Wnt/β-Catenin pathway, leading to hyperpigmentation.⁷ Although exposure to cigarette smoke decreases angiogenesis and would more likely lead to hyperpigmentation, nicotine exposure has been shown to increase angiogenesis, which could lead to increased blood flow and partially explain the protection against melasma demonstrated in our cohort.⁸ Future studies are needed to explore this relationship.

Limitations of our study include lack of information about melasma severity and information about prior melasma treatment in our cohort as well as possible misdiagnosis reported in the dataset.

Our results demonstrated that pre-existing depression and hypothyroidism as well as a history of radiation or estrogen and/or progesterone therapies are potential risk factors for melasma. Therefore, we recommend that patients with melasma be screened for depression and thyroid dysfunction, and patients undergoing radiation therapy or starting estrogen and/or progesterone therapy should be counseled on their increased risk for melasma. Future studies are needed to determine whether treatment of comorbidities such as hypothyroidism and depression improve melasma severity. The decreased risk for melasma associated with tobacco use also requires further investigation.

Acknowledgments—The All of Us Research Program is supported by the National Institutes of Health, Office of the Director: Regional Medical Centers: 1 OT2 OD026549; 1 OT2 OD026554; 1 OT2 OD026557; 1 OT2 OD026556; 1 OT2 OD026550; 1 OT2 OD 026552; 1 OT2 OD026553; 1 OT2 OD026548; 1 OT2 OD026551; 1 OT2 OD026555; IAA #: AOD 16037; Federally Qualified Health Centers: HHSN 263201600085U; Data and Research Center: 5 U2C OD023196; Biobank: 1 U24 OD023121; The Participant Center: U24 OD023176; Participant Technology Systems Center: 1 U24 OD023163; Communications and Engagement: 3 OT2 OD023205; 3 OT2 OD023206; and Community Partners: 1 OT2 OD025277; 3 OT2 OD025315; 1 OT2 OD025337; 1 OT2 OD025276.

In addition, the All of Us Research Program would not be possible without the partnership of its participants, who we gratefully acknowledge for their contributions and without whom this research would not have been possible. We also thank the All of Us Research Program for making the participant data examined in this study available to us.

Telemedicine interest, which was relatively quiescent prior to the COVID-19 pandemic, has surged in popularity in the past few years.¹ It can now be utilized seamlessly in dermatology practices to deliver exceptional patient care while reducing costs and travel time and offering dermatologists flexibility and improved work-life balance. Teledermatology applications include synchronous, asynchronous, and hybrid platforms.² For synchronous teledermatology, patient visits are carried out in real time with audio and video technology.³ For asynchronous teledermatology—also known as the store-and-forward model—the dermatologist receives the patient’s history and photographs and then renders an assessment and treatment plan.² Hybrid teledermatology uses real-time audio and video conferencing for history taking, assessment and treatment plan, and patient education, with photographs sent asynchronously.³ Telemedicine may not be initially intuitive or easy to integrate into clinical practice, but with time and effort, it will complement your dermatology practice, making it run more efficiently.

Patient Satisfaction With Teledermatology

Studies generally have shown very high patient satisfaction rates and shorter wait times with teledermatology vs in-person visits; for example, in a systematic review of 15 teledermatology studies including 7781 patients, more than 80% of participants reported high satisfaction with their telemedicine visit, with up to 92% reporting that they would choose to do a televisit again.⁴ In a retrospective analysis of 615 Zocdoc physicians, 65% of whom were dermatologists, mean wait times were 2.4 days for virtual appointments compared with 11.7 days for in-person appointments.⁵ Similarly, in a retrospective single-institution study, mean wait times for televisits were 14.3 days compared with 34.7 days for in-person referrals.⁶

Follow-Up Visits for Nail Disorders Via Teledermatology

Teledermatology may be particularly well suited for treating patients with nail disorders. In a prospective observational study, Onyeka et al⁷ accessed 813 images from 63 dermatology patients via teledermatology over a 6-month period to assess distance, focus, brightness, background, and image quality; of them, 83% were rated as high quality. Notably, images of nail disorders, skin growths, or pigmentation disorders were rated as having better image quality than images of inflammatory skin conditions (odds ratio [OR], 4.2-12.9 [P<.005]).⁷ In a retrospective study of 107 telemedicine visits for nail disorders during the COVID-19 pandemic, patients with longitudinal melanonychia were recommended for in-person visits for physical examination and dermoscopy, as were patients with suspected onychomycosis, who required nail plate sampling for diagnostic confirmation; however, approximately half of visits did not require in-person follow-up, including those patients with confirmed onychomycosis.⁸ Onychomycosis patients could be examined for clinical improvement and counseled on medication compliance via telemedicine. Other patients who did not require in-person follow-ups were those with traumatic nail disorders such as subungual hematoma and retronychia as well as those with body‐focused repetitive behaviors, including habit-tic nail deformity, onychophagia, and onychotillomania.⁸

Patients undergoing nail biopsies to rule out malignancies or to diagnose inflammatory nail disorders also may be managed via telemedicine. Patients for whom nail biopsies are recommended often are anxious about the procedure, which may be due to portrayal of nail trauma in the media⁹ or lack of accurate information on nail biopsies online.¹⁰ Therefore, counseling via telemedicine about the details of the procedure in a patient-friendly way (eg, showing an animated video and narrating it¹¹) can allay anxiety without the inconvenience, cost, and time missed from work associated with traveling to an in-person visit. In addition, postoperative counseling ideally is performed via telemedicine because complications following nail procedures are uncommon. In a retrospective study of 502 patients who underwent a nail biopsy at a single academic center, only 14 developed surgical site infections within 8 days on average (range, 5–13 days), with a higher infection risk in patients with type 2 ­diabetes mellitus (P<.0003).¹²

Advantages and Limitations

There are many benefits to incorporating telemedicine into dermatology practices, including reduced overhead costs, convenience and time saved for patients, and flexibility and improved work-life balance for dermatologists. In addition, because the number of in-person visits seen generally is fixed due to space constraints and work-hour restrictions, delegating follow-up visits to telemedicine can free up in-person slots for new patients and those needing procedures. However, there also are some inherent limitations to telemedicine: technology access, vision or hearing difficulties or low digital health literacy, or language barriers. In the prospective observational study by Onyeka et al⁷ analyzing 813 teledermatology images, patients aged 65 to 74 years sent in more clinically useful images (OR, 7.9) and images that were more often in focus (OR, 2.6) compared with patients older than 85 years.

Final Thoughts

Incorporation of telemedicine into dermatologic practice is a valuable tool for triaging patients with acute issues, improving patient care and health care access, making practices more efficient, and improving dermatologist flexibility and work-life balance. Further development of teledermatology to provide access to underserved populations prioritizing dermatologist reimbursement and progress on technologic innovations will make teledermatology even more useful in the coming years.

Telemedicine interest, which was relatively quiescent prior to the COVID-19 pandemic, has surged in popularity in the past few years.¹ It can now be utilized seamlessly in dermatology practices to deliver exceptional patient care while reducing costs and travel time and offering dermatologists flexibility and improved work-life balance. Teledermatology applications include synchronous, asynchronous, and hybrid platforms.² For synchronous teledermatology, patient visits are carried out in real time with audio and video technology.³ For asynchronous teledermatology—also known as the store-and-forward model—the dermatologist receives the patient’s history and photographs and then renders an assessment and treatment plan.² Hybrid teledermatology uses real-time audio and video conferencing for history taking, assessment and treatment plan, and patient education, with photographs sent asynchronously.³ Telemedicine may not be initially intuitive or easy to integrate into clinical practice, but with time and effort, it will complement your dermatology practice, making it run more efficiently.

Patient Satisfaction With Teledermatology

Studies generally have shown very high patient satisfaction rates and shorter wait times with teledermatology vs in-person visits; for example, in a systematic review of 15 teledermatology studies including 7781 patients, more than 80% of participants reported high satisfaction with their telemedicine visit, with up to 92% reporting that they would choose to do a televisit again.⁴ In a retrospective analysis of 615 Zocdoc physicians, 65% of whom were dermatologists, mean wait times were 2.4 days for virtual appointments compared with 11.7 days for in-person appointments.⁵ Similarly, in a retrospective single-institution study, mean wait times for televisits were 14.3 days compared with 34.7 days for in-person referrals.⁶

Follow-Up Visits for Nail Disorders Via Teledermatology

Teledermatology may be particularly well suited for treating patients with nail disorders. In a prospective observational study, Onyeka et al⁷ accessed 813 images from 63 dermatology patients via teledermatology over a 6-month period to assess distance, focus, brightness, background, and image quality; of them, 83% were rated as high quality. Notably, images of nail disorders, skin growths, or pigmentation disorders were rated as having better image quality than images of inflammatory skin conditions (odds ratio [OR], 4.2-12.9 [P<.005]).⁷ In a retrospective study of 107 telemedicine visits for nail disorders during the COVID-19 pandemic, patients with longitudinal melanonychia were recommended for in-person visits for physical examination and dermoscopy, as were patients with suspected onychomycosis, who required nail plate sampling for diagnostic confirmation; however, approximately half of visits did not require in-person follow-up, including those patients with confirmed onychomycosis.⁸ Onychomycosis patients could be examined for clinical improvement and counseled on medication compliance via telemedicine. Other patients who did not require in-person follow-ups were those with traumatic nail disorders such as subungual hematoma and retronychia as well as those with body‐focused repetitive behaviors, including habit-tic nail deformity, onychophagia, and onychotillomania.⁸

Patients undergoing nail biopsies to rule out malignancies or to diagnose inflammatory nail disorders also may be managed via telemedicine. Patients for whom nail biopsies are recommended often are anxious about the procedure, which may be due to portrayal of nail trauma in the media⁹ or lack of accurate information on nail biopsies online.¹⁰ Therefore, counseling via telemedicine about the details of the procedure in a patient-friendly way (eg, showing an animated video and narrating it¹¹) can allay anxiety without the inconvenience, cost, and time missed from work associated with traveling to an in-person visit. In addition, postoperative counseling ideally is performed via telemedicine because complications following nail procedures are uncommon. In a retrospective study of 502 patients who underwent a nail biopsy at a single academic center, only 14 developed surgical site infections within 8 days on average (range, 5–13 days), with a higher infection risk in patients with type 2 ­diabetes mellitus (P<.0003).¹²

Advantages and Limitations

There are many benefits to incorporating telemedicine into dermatology practices, including reduced overhead costs, convenience and time saved for patients, and flexibility and improved work-life balance for dermatologists. In addition, because the number of in-person visits seen generally is fixed due to space constraints and work-hour restrictions, delegating follow-up visits to telemedicine can free up in-person slots for new patients and those needing procedures. However, there also are some inherent limitations to telemedicine: technology access, vision or hearing difficulties or low digital health literacy, or language barriers. In the prospective observational study by Onyeka et al⁷ analyzing 813 teledermatology images, patients aged 65 to 74 years sent in more clinically useful images (OR, 7.9) and images that were more often in focus (OR, 2.6) compared with patients older than 85 years.

Final Thoughts

Incorporation of telemedicine into dermatologic practice is a valuable tool for triaging patients with acute issues, improving patient care and health care access, making practices more efficient, and improving dermatologist flexibility and work-life balance. Further development of teledermatology to provide access to underserved populations prioritizing dermatologist reimbursement and progress on technologic innovations will make teledermatology even more useful in the coming years.

Telemedicine interest, which was relatively quiescent prior to the COVID-19 pandemic, has surged in popularity in the past few years.¹ It can now be utilized seamlessly in dermatology practices to deliver exceptional patient care while reducing costs and travel time and offering dermatologists flexibility and improved work-life balance. Teledermatology applications include synchronous, asynchronous, and hybrid platforms.² For synchronous teledermatology, patient visits are carried out in real time with audio and video technology.³ For asynchronous teledermatology—also known as the store-and-forward model—the dermatologist receives the patient’s history and photographs and then renders an assessment and treatment plan.² Hybrid teledermatology uses real-time audio and video conferencing for history taking, assessment and treatment plan, and patient education, with photographs sent asynchronously.³ Telemedicine may not be initially intuitive or easy to integrate into clinical practice, but with time and effort, it will complement your dermatology practice, making it run more efficiently.

Patient Satisfaction With Teledermatology

Studies generally have shown very high patient satisfaction rates and shorter wait times with teledermatology vs in-person visits; for example, in a systematic review of 15 teledermatology studies including 7781 patients, more than 80% of participants reported high satisfaction with their telemedicine visit, with up to 92% reporting that they would choose to do a televisit again.⁴ In a retrospective analysis of 615 Zocdoc physicians, 65% of whom were dermatologists, mean wait times were 2.4 days for virtual appointments compared with 11.7 days for in-person appointments.⁵ Similarly, in a retrospective single-institution study, mean wait times for televisits were 14.3 days compared with 34.7 days for in-person referrals.⁶

Follow-Up Visits for Nail Disorders Via Teledermatology

Teledermatology may be particularly well suited for treating patients with nail disorders. In a prospective observational study, Onyeka et al⁷ accessed 813 images from 63 dermatology patients via teledermatology over a 6-month period to assess distance, focus, brightness, background, and image quality; of them, 83% were rated as high quality. Notably, images of nail disorders, skin growths, or pigmentation disorders were rated as having better image quality than images of inflammatory skin conditions (odds ratio [OR], 4.2-12.9 [P<.005]).⁷ In a retrospective study of 107 telemedicine visits for nail disorders during the COVID-19 pandemic, patients with longitudinal melanonychia were recommended for in-person visits for physical examination and dermoscopy, as were patients with suspected onychomycosis, who required nail plate sampling for diagnostic confirmation; however, approximately half of visits did not require in-person follow-up, including those patients with confirmed onychomycosis.⁸ Onychomycosis patients could be examined for clinical improvement and counseled on medication compliance via telemedicine. Other patients who did not require in-person follow-ups were those with traumatic nail disorders such as subungual hematoma and retronychia as well as those with body‐focused repetitive behaviors, including habit-tic nail deformity, onychophagia, and onychotillomania.⁸

Patients undergoing nail biopsies to rule out malignancies or to diagnose inflammatory nail disorders also may be managed via telemedicine. Patients for whom nail biopsies are recommended often are anxious about the procedure, which may be due to portrayal of nail trauma in the media⁹ or lack of accurate information on nail biopsies online.¹⁰ Therefore, counseling via telemedicine about the details of the procedure in a patient-friendly way (eg, showing an animated video and narrating it¹¹) can allay anxiety without the inconvenience, cost, and time missed from work associated with traveling to an in-person visit. In addition, postoperative counseling ideally is performed via telemedicine because complications following nail procedures are uncommon. In a retrospective study of 502 patients who underwent a nail biopsy at a single academic center, only 14 developed surgical site infections within 8 days on average (range, 5–13 days), with a higher infection risk in patients with type 2 ­diabetes mellitus (P<.0003).¹²

Advantages and Limitations

There are many benefits to incorporating telemedicine into dermatology practices, including reduced overhead costs, convenience and time saved for patients, and flexibility and improved work-life balance for dermatologists. In addition, because the number of in-person visits seen generally is fixed due to space constraints and work-hour restrictions, delegating follow-up visits to telemedicine can free up in-person slots for new patients and those needing procedures. However, there also are some inherent limitations to telemedicine: technology access, vision or hearing difficulties or low digital health literacy, or language barriers. In the prospective observational study by Onyeka et al⁷ analyzing 813 teledermatology images, patients aged 65 to 74 years sent in more clinically useful images (OR, 7.9) and images that were more often in focus (OR, 2.6) compared with patients older than 85 years.

Final Thoughts

Incorporation of telemedicine into dermatologic practice is a valuable tool for triaging patients with acute issues, improving patient care and health care access, making practices more efficient, and improving dermatologist flexibility and work-life balance. Further development of teledermatology to provide access to underserved populations prioritizing dermatologist reimbursement and progress on technologic innovations will make teledermatology even more useful in the coming years.

Nail disorders are common among pediatric patients but often are underdiagnosed or misdiagnosed because of their unique disease manifestations. These conditions may severely impact quality of life. There are few nail disease clinical trials that include children. Consequently, most treatment recommendations are based on case series and expert consensus recommendations. We review inflammatory and infectious nail disorders in pediatric patients. By describing characteristics, clinical manifestations, and management approaches for these conditions, we aim to provide guidance to dermatologists in their diagnosis and treatment.

INFLAMMATORY NAIL DISORDERS

Nail Psoriasis

Nail involvement in children with psoriasis is common, with prevalence estimates ranging from 17% to 39.2%.¹ Nail matrix psoriasis may manifest with pitting (large irregular pits) and leukonychia as well as chromonychia and nail plate crumbling. Onycholysis, oil drop spots (salmon patches), and subungual hyperkeratosis can be seen in nail bed psoriasis. Nail pitting is the most frequently observed clinical finding (Figure 1).^2,3 In a cross-sectional multicenter study of 313 children with cutaneous psoriasis in France, nail findings were present in 101 patients (32.3%). There were associations between nail findings and presence of psoriatic arthritis (P=.03), palmoplantar psoriasis (P<.001), and severity of psoriatic disease, defined as use of systemic treatment with phototherapy (psoralen plus UVA, UVB), traditional systemic treatment (acitretin, methotrexate, cyclosporine), or a biologic (P=.003).⁴

Topical steroids and vitamin D analogues may be used with or without occlusion and may be efficacious.⁵ Several case reports describe systemic treatments for psoriasis in children, including methotrexate, acitretin, and apremilast (approved for children 6 years and older for plaque psoriasis by the US Food and Drug Administration [FDA]).² There are 5 biologic drugs currently approved for the treatment of pediatric psoriasis—adalimumab, etanercept, ustekinumab, secukinumab, ixekizumab—and 6 drugs currently undergoing phase 3 studies—brodalumab, guselkumab, risankizumab, tildrakizumab, certolizumab pegol, and deucravacitinib (Table 1).^6-15 Adalimumab is specifically approved for moderate to severe nail psoriasis in adults 18 years and older.

Intralesional steroid injections are sometimes useful in the management of nail matrix psoriasis; however, appropriate patient selection is critical due to the pain associated with the procedure. In a prospective study of 16 children (age range, 9–17 years) with nail psoriasis treated with intralesional triamcinolone (ILTAC) 2.5 to 5 mg/mL every 4 to 8 weeks for a minimum of 3 to 6 months, 9 patients achieved resolution and 6 had improvement of clinical findings.¹⁶ Local adverse events were mild, including injection-site pain (66%), subungual hematoma (n=1), Beau lines (n=1), proximal nail fold hypopigmentation (n=2), and proximal nail fold atrophy (n=2). Because the proximal nail fold in children is thinner than in adults, there may be an increased risk for nail fold hypopigmentation and atrophy in children. Therefore, a maximum ILTAC concentration of 2.5 mg/mL with 0.2 mL maximum volume per nail per session is recommended for children younger than 15 years.¹⁶

Nail Lichen Planus

Nail lichen planus (NLP) is uncommon in children, with few biopsy-proven cases documented in the literature.¹⁷ Common clinical findings are onychorrhexis, nail plate thinning, fissuring, splitting, and atrophy with koilonychia.⁵ Although pterygium development (irreversible nail matrix scarring) is uncommon in pediatric patients, NLP can be progressive and may cause irreversible destruction of the nail matrix and subsequent nail loss, warranting therapeutic intervention.¹⁸

Treatment of NLP may be difficult, as there are no options that work in all patients. Current literature supports the use of systemic corticosteroids or ILTAC for the treatment of NLP; however, recurrence rates can be high. According to an expert consensus paper on NLP treatment, ILTAC may be injected in a concentration of 2.5, 5, or 10 mg/mL according to disease severity.¹⁹ In severe or resistant cases, intramuscular (IM) triamcinolone may be considered, especially if more than 3 nails are affected. A dosage of 0.5 to 1 mg/kg/mo for at least 3 to 6 months is recommended for both children and adults, with 1 mg/kg/mo recommended in the active treatment phase (first 2–3 months).¹⁹ In a retrospective review of 5 pediatric patients with NLP treated with IM triamcinolone 0.5 mg/kg/mo, 3 patients had resolution and 2 improved with treatment.²⁰ In a prospective study of 10 children with NLP, IM triamcinolone at a dosage of 0.5 to 1 mg/kg every 30 days for 3 to 6 months resulted in resolution of nail findings in 9 patients.¹⁷ In a prospective study of 14 pediatric patients with NLP treated with 2.5 to 5 mg/mL of ILTAC, 10 achieved resolution and 3 improved.¹⁶

Intralesional triamcinolone injections may be better suited for teenagers compared to younger children who may be more apprehensive of needles. To minimize pain, it is recommended to inject ILTAC slowly at room temperature, with use of “talkesthesia” and vibration devices, 1% lidocaine, or ethyl chloride spray.¹⁸

Trachyonychia

Trachyonychia is characterized by the presence of sandpaperlike nails. It manifests with brittle thin nails with longitudinal ridging, onychoschizia, and thickened hyperkeratotic cuticles. Trachyonychia typically involves multiple nails, with a peak age of onset between 3 and 12 years.^21,22 There are 2 variants: the opaque type with rough longitudinal ridging, and the shiny variant with opalescent nails and pits that reflect light. The opaque variant is more common and is associated with psoriasis, whereas the shiny variant is less common and is associated with alopecia areata.²³ Although most cases are idiopathic, some are associated with psoriasis and alopecia areata, as previously noted, as well as atopic dermatitis (AD) and lichen planus.^22,24

Fortunately, trachyonychia does not lead to permanent nail damage or pterygium, making treatment primarily focused on addressing functional and cosmetic concerns.²⁴ Spontaneous resolution occurs in approximately 50% of patients. In a prospective study of 11 patients with idiopathic trachyonychia, there was partial improvement in 5 of 9 patients treated with topical steroids, 1 with only petrolatum, and 1 with vitamin supplements. Complete resolution was reported in 1 patient treated with topical steroids.²⁵ Because trachyonychia often is self-resolving, no treatment is required and a conservative approach is strongly recommended.²⁶ Treatment options include topical corticosteroids, tazarotene, and 5-fluorouracil. Intralesional triamcinolone, systemic cyclosporine, retinoids, systemic corticosteroids, and tofacitinib have been described in case reports, though none of these have been shown to be 100% efficacious.²⁴

Nail Lichen Striatus

Lichen striatus involving the nail is uncommon and is characterized by onycholysis, longitudinal ridging, ­splitting, and fraying, as well as what appears to be a subungual tumor. It can encompass the entire nail or may be isolated to a portion of the nail (Figure 2). Usually, a Blaschko-linear array of flesh-colored papules on the more proximal digit directly adjacent to the nail dystrophy will be seen, though nail findings can occur in ­isolation.^27-29 The underlying pathophysiology is not clear; however, one hypothesis is that a triggering event, such as trauma, induces the expression of antigens that elicit a self-limiting immune-mediated response by CD8 T lymphocytes.³⁰

Generally, nail lichen striatus spontaneously resolves in 1 to 2 years without treatment. In a prospective study of 5 patients with nail lichen striatus, the median time to resolution was 22.6 months (range, 10–30 months).³¹ Topical steroids may be used for pruritus. In one case report, a 3-year-old boy with nail lichen striatus of 4 months’ duration was treated with tacrolimus ointment 0.03% daily for 3 months.²⁸

Nail AD

Nail changes with AD may be more common in adults than children or are underreported. In a study of 777 adults with AD, nail dystrophy was present in 124 patients (16%), whereas in a study of 250 pediatric patients with AD (aged 0-2 years), nail dystrophy was present in only 4 patients.^32,33

Periungual inflammation from AD causes the nail changes.³⁴ In a cross-sectional study of 24 pediatric patients with nail dystrophy due to AD, transverse grooves (Beau lines) were present in 25% (6/24), nail pitting in 16.7% (4/24), koilonychia in 16.7% (4/24), trachyonychia in 12.5% (3/24), leukonychia in 12.5% (3/24), brachyonychia in 8.3% (2/24), melanonychia in 8.3% (2/24), onychomadesis in 8.3% (2/24), onychoschizia in 8.3% (2/24), and onycholysis in 8.3% (2/24). There was an association between disease severity and presence of toenail dystrophy (P=.03).³⁵

Topical steroids with or without occlusion can be used to treat nail changes. Although there is limited literature describing the treatment of nail AD in children, a 61-year-old man with nail changes associated with AD achieved resolution with 3 months of treatment with dupilumab.³⁶ Anecdotally, most patients will improve with usual cutaneous AD management.

INFECTIOUS NAIL DISORDERS

Viral Infections

Hand, Foot, and Mouth Disease—Hand, foot, and mouth disease (HFMD) is a common childhood viral infection caused by various enteroviruses, most commonly coxsackievirus A16, with the A6 variant causing more severe disease. Fever and painful vesicles involving the oral mucosa as well as palms and soles give the disease its name. Nail changes are common. In a prospective study involving 130 patients with laboratory-confirmed coxsackievirus CA6 serotype infection, 37% developed onychomadesis vs only 5% of 145 cases with non-CA6 enterovirus infection who developed nail findings. There was an association between CA6 infection and presence of nail changes (P<.001).³⁷

Findings ranging from transverse grooves (Beau lines) to complete nail shedding (onychomadesis)(Figure 3) may be seen.^38,39 Nail findings in HFMD are due to transient inhibition of nail growth and present approximately 3 to 6 weeks after infection.⁴⁰ Onychomadesis is seen in 30% to 68% of patients with HFMD.^37,41,42 Nail findings in HFMD spontaneously resolve with nail growth (2–3 mm per month for fingernails and 1 mm per month for toenails) and do not require specific treatment. Although the appearance of nail changes associated with HFMD can be disturbing, dermatologists can reassure children and their parents that the nails will resolve with the next cycle of growth.

Kawasaki Disease—Kawasaki disease (KD) is a vasculitis primarily affecting children and infants. Although the specific pathogen and pathophysiology is not entirely clear, clinical observations have suggested an infectious cause, most likely a virus.⁴³ In Japan, more than 15,000 cases of KD are documented annually, while approximately 4200 cases are seen in the United States.⁴⁴ In a prospective study from 1984 to 1990, 4 of 26 (15.4%) patients with KD presented with nail manifestations during the late acute phase or early convalescent phase of disease. There were no significant associations between nail dystrophy and severity of KD, such as coronary artery aneurysm.⁴⁵

Nail changes reported in children with KD include onychomadesis, onycholysis, orange-brown chromonychia, splinter hemorrhages, Beau lines, and pincer nails. In a review of nail changes associated with KD from 1980 to 2021, orange-brown transverse chromonychia, which may evolve into transverse leukonychia, was the most common nail finding reported, occurring in 17 of 31 (54.8%) patients.⁴⁴ It has been hypothesized that nail changes may result from blood flow disturbance due to the underlying vasculitis.⁴⁶ Nail changes appear several weeks after the onset of fever and are self-limited. Resolution occurs with nail growth, with no treatment required.

FUNGAL INFECTIONS

Onychomycosis

Onychomycosis is a fungal infection of the nails that occurs in 0.2% to 5.5% of pediatric patients, and its prevalence may be increasing, which may be due to environmental factors or increased rates of diabetes mellitus and obesity in the pediatric population.⁴⁷ Onychomycosis represents 15.5% of nail dystrophies in pediatric patients.⁴⁸ Some dermatologists treat presumptive onychomycosis without confirmation; however, we do not recommend that approach. Because the differential is broad and the duration of treatment is long, mycologic examination (potassium hydroxide preparation, fungal culture, polymerase chain reaction, and/or histopathology) should be obtained to confirm onychomycosis prior to initiation of antifungal management. Family members of affected individuals should be evaluated and treated, if indicated, for onychomycosis and tinea pedis, as household transmission is common.

Currently, there are 2 topical FDA-approved treatments for pediatric onychomycosis in children 6 years and older (Table 2).^49,50 There is a discussion of the need for confirmatory testing for onychomycosis in children, particularly when systemic treatment is prescribed. In a retrospective review of 269 pediatric patients with onychomycosis prescribed terbinafine, 53.5% (n=144) underwent laboratory monitoring of liver function and complete blood cell counts, and 12.5% had grade 1 laboratory abnormalities either prior to (12/144 [8.3%]) or during (6/144 [4.2%]) therapy.⁵¹ Baseline transaminase monitoring is recommended, though subsequent routine laboratory monitoring in healthy children may have limited utility with associated increased costs, incidental findings, and patient discomfort and likely is not needed.⁵¹

Pediatric onychomycosis responds better to topical therapy than adult disease, and pediatric patients do not always require systemic treatment.⁵² Ciclopirox is not FDA approved for the treatment of pediatric onychomycosis, but in a 32-week clinical trial of ciclopirox lacquer 8% use in 40 patients, 77% (27/35) of treated patients achieved mycologic cure. Overall, 71% of treated patients (25/35) vs 22% (2/9) of controls achieved efficacy (defined as investigator global assessment score of 2 or lower).⁵² In an open-label, single-arm clinical trial assessing tavaborole solution 5% applied once daily for 48 weeks for the treatment of toenail onychomycosis in pediatric patients (aged 6–17 years), 36.2% (20/55) of patients achieved mycologic cure, and 8.5% (5/55) achieved complete cure at week 52 with mild or minimal adverse effects.⁵³ In an open-label, phase 4 study of the safety and efficacy of efinaconazole solution 10% applied once daily for 48 weeks in pediatric patients (aged 6 to 16 years) (n=60), 65% (35/60) achieved mycologic cure, 42% (25/60) achieved clinical cure, and 40% (24/60) achieved complete cure at 52 weeks. The most common adverse effects of efina­conazole were local and included ingrown toenail (1/60), application-site dermatitis (1/60), application-site vesicles (1/60), and application-site pain (1/60).⁵⁴

In a systematic review of systemic antifungals for onychomycosis in 151 pediatric patients, itraconazole, fluconazole, griseofulvin, and terbinafine resulted in complete cure rates similar to those of the adult population, with excellent safety profiles.⁵⁵ Depending on the situation, initiation of treatment with topical medications followed by addition of systemic antifungal agents only if needed may be an appropriate course of action.

BACTERIAL INFECTIONS

Acute Paronychia

Acute paronychia is a nail-fold infection that develops after the protective nail barrier has been compromised.⁵⁶ In children, thumb-sucking, nail-biting, frequent oral manipulation of the digits, and poor skin hygiene are risk factors. Acute paronychia also may develop in association with congenital malalignment of the great toenails.⁵⁷

Clinical manifestations include localized pain, erythema, and nail fold edema (Figure 4). Purulent material and abscess formation may ensue. Staphylococcus aureus as well as methicillin-resistant S aureus and Streptococcus pyogenes are classically the most common causes of acute paronychia. Treatment of paronychia is based on severity. In mild cases, warm soaks with topical antibiotics are indicated. Oral antibiotics should be prescribed for more severe presentations. If there is no improvement after 48 hours, surgical drainage is required to facilitate healing.⁵⁶

FINAL THOUGHTS

Inflammatory and infectious nail disorders in children are relatively common and may impact the physical and emotional well-being of young patients. By understanding the distinctive features of these nail disorders in pediatric patients, dermatologists can provide anticipatory guidance and informed treatment options to children and their parents. Further research is needed to expand our understanding of pediatric nail disorders and create targeted therapeutic interventions, particularly for NLP and psoriasis.

Nail disorders are common among pediatric patients but often are underdiagnosed or misdiagnosed because of their unique disease manifestations. These conditions may severely impact quality of life. There are few nail disease clinical trials that include children. Consequently, most treatment recommendations are based on case series and expert consensus recommendations. We review inflammatory and infectious nail disorders in pediatric patients. By describing characteristics, clinical manifestations, and management approaches for these conditions, we aim to provide guidance to dermatologists in their diagnosis and treatment.

INFLAMMATORY NAIL DISORDERS

Nail Psoriasis

Nail involvement in children with psoriasis is common, with prevalence estimates ranging from 17% to 39.2%.¹ Nail matrix psoriasis may manifest with pitting (large irregular pits) and leukonychia as well as chromonychia and nail plate crumbling. Onycholysis, oil drop spots (salmon patches), and subungual hyperkeratosis can be seen in nail bed psoriasis. Nail pitting is the most frequently observed clinical finding (Figure 1).^2,3 In a cross-sectional multicenter study of 313 children with cutaneous psoriasis in France, nail findings were present in 101 patients (32.3%). There were associations between nail findings and presence of psoriatic arthritis (P=.03), palmoplantar psoriasis (P<.001), and severity of psoriatic disease, defined as use of systemic treatment with phototherapy (psoralen plus UVA, UVB), traditional systemic treatment (acitretin, methotrexate, cyclosporine), or a biologic (P=.003).⁴

Topical steroids and vitamin D analogues may be used with or without occlusion and may be efficacious.⁵ Several case reports describe systemic treatments for psoriasis in children, including methotrexate, acitretin, and apremilast (approved for children 6 years and older for plaque psoriasis by the US Food and Drug Administration [FDA]).² There are 5 biologic drugs currently approved for the treatment of pediatric psoriasis—adalimumab, etanercept, ustekinumab, secukinumab, ixekizumab—and 6 drugs currently undergoing phase 3 studies—brodalumab, guselkumab, risankizumab, tildrakizumab, certolizumab pegol, and deucravacitinib (Table 1).^6-15 Adalimumab is specifically approved for moderate to severe nail psoriasis in adults 18 years and older.

Intralesional steroid injections are sometimes useful in the management of nail matrix psoriasis; however, appropriate patient selection is critical due to the pain associated with the procedure. In a prospective study of 16 children (age range, 9–17 years) with nail psoriasis treated with intralesional triamcinolone (ILTAC) 2.5 to 5 mg/mL every 4 to 8 weeks for a minimum of 3 to 6 months, 9 patients achieved resolution and 6 had improvement of clinical findings.¹⁶ Local adverse events were mild, including injection-site pain (66%), subungual hematoma (n=1), Beau lines (n=1), proximal nail fold hypopigmentation (n=2), and proximal nail fold atrophy (n=2). Because the proximal nail fold in children is thinner than in adults, there may be an increased risk for nail fold hypopigmentation and atrophy in children. Therefore, a maximum ILTAC concentration of 2.5 mg/mL with 0.2 mL maximum volume per nail per session is recommended for children younger than 15 years.¹⁶

Nail Lichen Planus

Nail lichen planus (NLP) is uncommon in children, with few biopsy-proven cases documented in the literature.¹⁷ Common clinical findings are onychorrhexis, nail plate thinning, fissuring, splitting, and atrophy with koilonychia.⁵ Although pterygium development (irreversible nail matrix scarring) is uncommon in pediatric patients, NLP can be progressive and may cause irreversible destruction of the nail matrix and subsequent nail loss, warranting therapeutic intervention.¹⁸

Treatment of NLP may be difficult, as there are no options that work in all patients. Current literature supports the use of systemic corticosteroids or ILTAC for the treatment of NLP; however, recurrence rates can be high. According to an expert consensus paper on NLP treatment, ILTAC may be injected in a concentration of 2.5, 5, or 10 mg/mL according to disease severity.¹⁹ In severe or resistant cases, intramuscular (IM) triamcinolone may be considered, especially if more than 3 nails are affected. A dosage of 0.5 to 1 mg/kg/mo for at least 3 to 6 months is recommended for both children and adults, with 1 mg/kg/mo recommended in the active treatment phase (first 2–3 months).¹⁹ In a retrospective review of 5 pediatric patients with NLP treated with IM triamcinolone 0.5 mg/kg/mo, 3 patients had resolution and 2 improved with treatment.²⁰ In a prospective study of 10 children with NLP, IM triamcinolone at a dosage of 0.5 to 1 mg/kg every 30 days for 3 to 6 months resulted in resolution of nail findings in 9 patients.¹⁷ In a prospective study of 14 pediatric patients with NLP treated with 2.5 to 5 mg/mL of ILTAC, 10 achieved resolution and 3 improved.¹⁶

Intralesional triamcinolone injections may be better suited for teenagers compared to younger children who may be more apprehensive of needles. To minimize pain, it is recommended to inject ILTAC slowly at room temperature, with use of “talkesthesia” and vibration devices, 1% lidocaine, or ethyl chloride spray.¹⁸

Trachyonychia

Trachyonychia is characterized by the presence of sandpaperlike nails. It manifests with brittle thin nails with longitudinal ridging, onychoschizia, and thickened hyperkeratotic cuticles. Trachyonychia typically involves multiple nails, with a peak age of onset between 3 and 12 years.^21,22 There are 2 variants: the opaque type with rough longitudinal ridging, and the shiny variant with opalescent nails and pits that reflect light. The opaque variant is more common and is associated with psoriasis, whereas the shiny variant is less common and is associated with alopecia areata.²³ Although most cases are idiopathic, some are associated with psoriasis and alopecia areata, as previously noted, as well as atopic dermatitis (AD) and lichen planus.^22,24

Fortunately, trachyonychia does not lead to permanent nail damage or pterygium, making treatment primarily focused on addressing functional and cosmetic concerns.²⁴ Spontaneous resolution occurs in approximately 50% of patients. In a prospective study of 11 patients with idiopathic trachyonychia, there was partial improvement in 5 of 9 patients treated with topical steroids, 1 with only petrolatum, and 1 with vitamin supplements. Complete resolution was reported in 1 patient treated with topical steroids.²⁵ Because trachyonychia often is self-resolving, no treatment is required and a conservative approach is strongly recommended.²⁶ Treatment options include topical corticosteroids, tazarotene, and 5-fluorouracil. Intralesional triamcinolone, systemic cyclosporine, retinoids, systemic corticosteroids, and tofacitinib have been described in case reports, though none of these have been shown to be 100% efficacious.²⁴

Nail Lichen Striatus

Lichen striatus involving the nail is uncommon and is characterized by onycholysis, longitudinal ridging, ­splitting, and fraying, as well as what appears to be a subungual tumor. It can encompass the entire nail or may be isolated to a portion of the nail (Figure 2). Usually, a Blaschko-linear array of flesh-colored papules on the more proximal digit directly adjacent to the nail dystrophy will be seen, though nail findings can occur in ­isolation.^27-29 The underlying pathophysiology is not clear; however, one hypothesis is that a triggering event, such as trauma, induces the expression of antigens that elicit a self-limiting immune-mediated response by CD8 T lymphocytes.³⁰

Generally, nail lichen striatus spontaneously resolves in 1 to 2 years without treatment. In a prospective study of 5 patients with nail lichen striatus, the median time to resolution was 22.6 months (range, 10–30 months).³¹ Topical steroids may be used for pruritus. In one case report, a 3-year-old boy with nail lichen striatus of 4 months’ duration was treated with tacrolimus ointment 0.03% daily for 3 months.²⁸

Nail AD

Nail changes with AD may be more common in adults than children or are underreported. In a study of 777 adults with AD, nail dystrophy was present in 124 patients (16%), whereas in a study of 250 pediatric patients with AD (aged 0-2 years), nail dystrophy was present in only 4 patients.^32,33

Periungual inflammation from AD causes the nail changes.³⁴ In a cross-sectional study of 24 pediatric patients with nail dystrophy due to AD, transverse grooves (Beau lines) were present in 25% (6/24), nail pitting in 16.7% (4/24), koilonychia in 16.7% (4/24), trachyonychia in 12.5% (3/24), leukonychia in 12.5% (3/24), brachyonychia in 8.3% (2/24), melanonychia in 8.3% (2/24), onychomadesis in 8.3% (2/24), onychoschizia in 8.3% (2/24), and onycholysis in 8.3% (2/24). There was an association between disease severity and presence of toenail dystrophy (P=.03).³⁵

Topical steroids with or without occlusion can be used to treat nail changes. Although there is limited literature describing the treatment of nail AD in children, a 61-year-old man with nail changes associated with AD achieved resolution with 3 months of treatment with dupilumab.³⁶ Anecdotally, most patients will improve with usual cutaneous AD management.

INFECTIOUS NAIL DISORDERS

Viral Infections

Hand, Foot, and Mouth Disease—Hand, foot, and mouth disease (HFMD) is a common childhood viral infection caused by various enteroviruses, most commonly coxsackievirus A16, with the A6 variant causing more severe disease. Fever and painful vesicles involving the oral mucosa as well as palms and soles give the disease its name. Nail changes are common. In a prospective study involving 130 patients with laboratory-confirmed coxsackievirus CA6 serotype infection, 37% developed onychomadesis vs only 5% of 145 cases with non-CA6 enterovirus infection who developed nail findings. There was an association between CA6 infection and presence of nail changes (P<.001).³⁷

Findings ranging from transverse grooves (Beau lines) to complete nail shedding (onychomadesis)(Figure 3) may be seen.^38,39 Nail findings in HFMD are due to transient inhibition of nail growth and present approximately 3 to 6 weeks after infection.⁴⁰ Onychomadesis is seen in 30% to 68% of patients with HFMD.^37,41,42 Nail findings in HFMD spontaneously resolve with nail growth (2–3 mm per month for fingernails and 1 mm per month for toenails) and do not require specific treatment. Although the appearance of nail changes associated with HFMD can be disturbing, dermatologists can reassure children and their parents that the nails will resolve with the next cycle of growth.

Kawasaki Disease—Kawasaki disease (KD) is a vasculitis primarily affecting children and infants. Although the specific pathogen and pathophysiology is not entirely clear, clinical observations have suggested an infectious cause, most likely a virus.⁴³ In Japan, more than 15,000 cases of KD are documented annually, while approximately 4200 cases are seen in the United States.⁴⁴ In a prospective study from 1984 to 1990, 4 of 26 (15.4%) patients with KD presented with nail manifestations during the late acute phase or early convalescent phase of disease. There were no significant associations between nail dystrophy and severity of KD, such as coronary artery aneurysm.⁴⁵

Nail changes reported in children with KD include onychomadesis, onycholysis, orange-brown chromonychia, splinter hemorrhages, Beau lines, and pincer nails. In a review of nail changes associated with KD from 1980 to 2021, orange-brown transverse chromonychia, which may evolve into transverse leukonychia, was the most common nail finding reported, occurring in 17 of 31 (54.8%) patients.⁴⁴ It has been hypothesized that nail changes may result from blood flow disturbance due to the underlying vasculitis.⁴⁶ Nail changes appear several weeks after the onset of fever and are self-limited. Resolution occurs with nail growth, with no treatment required.

FUNGAL INFECTIONS

Onychomycosis

Onychomycosis is a fungal infection of the nails that occurs in 0.2% to 5.5% of pediatric patients, and its prevalence may be increasing, which may be due to environmental factors or increased rates of diabetes mellitus and obesity in the pediatric population.⁴⁷ Onychomycosis represents 15.5% of nail dystrophies in pediatric patients.⁴⁸ Some dermatologists treat presumptive onychomycosis without confirmation; however, we do not recommend that approach. Because the differential is broad and the duration of treatment is long, mycologic examination (potassium hydroxide preparation, fungal culture, polymerase chain reaction, and/or histopathology) should be obtained to confirm onychomycosis prior to initiation of antifungal management. Family members of affected individuals should be evaluated and treated, if indicated, for onychomycosis and tinea pedis, as household transmission is common.

Currently, there are 2 topical FDA-approved treatments for pediatric onychomycosis in children 6 years and older (Table 2).^49,50 There is a discussion of the need for confirmatory testing for onychomycosis in children, particularly when systemic treatment is prescribed. In a retrospective review of 269 pediatric patients with onychomycosis prescribed terbinafine, 53.5% (n=144) underwent laboratory monitoring of liver function and complete blood cell counts, and 12.5% had grade 1 laboratory abnormalities either prior to (12/144 [8.3%]) or during (6/144 [4.2%]) therapy.⁵¹ Baseline transaminase monitoring is recommended, though subsequent routine laboratory monitoring in healthy children may have limited utility with associated increased costs, incidental findings, and patient discomfort and likely is not needed.⁵¹

Pediatric onychomycosis responds better to topical therapy than adult disease, and pediatric patients do not always require systemic treatment.⁵² Ciclopirox is not FDA approved for the treatment of pediatric onychomycosis, but in a 32-week clinical trial of ciclopirox lacquer 8% use in 40 patients, 77% (27/35) of treated patients achieved mycologic cure. Overall, 71% of treated patients (25/35) vs 22% (2/9) of controls achieved efficacy (defined as investigator global assessment score of 2 or lower).⁵² In an open-label, single-arm clinical trial assessing tavaborole solution 5% applied once daily for 48 weeks for the treatment of toenail onychomycosis in pediatric patients (aged 6–17 years), 36.2% (20/55) of patients achieved mycologic cure, and 8.5% (5/55) achieved complete cure at week 52 with mild or minimal adverse effects.⁵³ In an open-label, phase 4 study of the safety and efficacy of efinaconazole solution 10% applied once daily for 48 weeks in pediatric patients (aged 6 to 16 years) (n=60), 65% (35/60) achieved mycologic cure, 42% (25/60) achieved clinical cure, and 40% (24/60) achieved complete cure at 52 weeks. The most common adverse effects of efina­conazole were local and included ingrown toenail (1/60), application-site dermatitis (1/60), application-site vesicles (1/60), and application-site pain (1/60).⁵⁴

In a systematic review of systemic antifungals for onychomycosis in 151 pediatric patients, itraconazole, fluconazole, griseofulvin, and terbinafine resulted in complete cure rates similar to those of the adult population, with excellent safety profiles.⁵⁵ Depending on the situation, initiation of treatment with topical medications followed by addition of systemic antifungal agents only if needed may be an appropriate course of action.

BACTERIAL INFECTIONS

Acute Paronychia

Acute paronychia is a nail-fold infection that develops after the protective nail barrier has been compromised.⁵⁶ In children, thumb-sucking, nail-biting, frequent oral manipulation of the digits, and poor skin hygiene are risk factors. Acute paronychia also may develop in association with congenital malalignment of the great toenails.⁵⁷

Clinical manifestations include localized pain, erythema, and nail fold edema (Figure 4). Purulent material and abscess formation may ensue. Staphylococcus aureus as well as methicillin-resistant S aureus and Streptococcus pyogenes are classically the most common causes of acute paronychia. Treatment of paronychia is based on severity. In mild cases, warm soaks with topical antibiotics are indicated. Oral antibiotics should be prescribed for more severe presentations. If there is no improvement after 48 hours, surgical drainage is required to facilitate healing.⁵⁶

FINAL THOUGHTS

Inflammatory and infectious nail disorders in children are relatively common and may impact the physical and emotional well-being of young patients. By understanding the distinctive features of these nail disorders in pediatric patients, dermatologists can provide anticipatory guidance and informed treatment options to children and their parents. Further research is needed to expand our understanding of pediatric nail disorders and create targeted therapeutic interventions, particularly for NLP and psoriasis.

Nail disorders are common among pediatric patients but often are underdiagnosed or misdiagnosed because of their unique disease manifestations. These conditions may severely impact quality of life. There are few nail disease clinical trials that include children. Consequently, most treatment recommendations are based on case series and expert consensus recommendations. We review inflammatory and infectious nail disorders in pediatric patients. By describing characteristics, clinical manifestations, and management approaches for these conditions, we aim to provide guidance to dermatologists in their diagnosis and treatment.

INFLAMMATORY NAIL DISORDERS

Nail Psoriasis

Nail involvement in children with psoriasis is common, with prevalence estimates ranging from 17% to 39.2%.¹ Nail matrix psoriasis may manifest with pitting (large irregular pits) and leukonychia as well as chromonychia and nail plate crumbling. Onycholysis, oil drop spots (salmon patches), and subungual hyperkeratosis can be seen in nail bed psoriasis. Nail pitting is the most frequently observed clinical finding (Figure 1).^2,3 In a cross-sectional multicenter study of 313 children with cutaneous psoriasis in France, nail findings were present in 101 patients (32.3%). There were associations between nail findings and presence of psoriatic arthritis (P=.03), palmoplantar psoriasis (P<.001), and severity of psoriatic disease, defined as use of systemic treatment with phototherapy (psoralen plus UVA, UVB), traditional systemic treatment (acitretin, methotrexate, cyclosporine), or a biologic (P=.003).⁴

Topical steroids and vitamin D analogues may be used with or without occlusion and may be efficacious.⁵ Several case reports describe systemic treatments for psoriasis in children, including methotrexate, acitretin, and apremilast (approved for children 6 years and older for plaque psoriasis by the US Food and Drug Administration [FDA]).² There are 5 biologic drugs currently approved for the treatment of pediatric psoriasis—adalimumab, etanercept, ustekinumab, secukinumab, ixekizumab—and 6 drugs currently undergoing phase 3 studies—brodalumab, guselkumab, risankizumab, tildrakizumab, certolizumab pegol, and deucravacitinib (Table 1).^6-15 Adalimumab is specifically approved for moderate to severe nail psoriasis in adults 18 years and older.

Intralesional steroid injections are sometimes useful in the management of nail matrix psoriasis; however, appropriate patient selection is critical due to the pain associated with the procedure. In a prospective study of 16 children (age range, 9–17 years) with nail psoriasis treated with intralesional triamcinolone (ILTAC) 2.5 to 5 mg/mL every 4 to 8 weeks for a minimum of 3 to 6 months, 9 patients achieved resolution and 6 had improvement of clinical findings.¹⁶ Local adverse events were mild, including injection-site pain (66%), subungual hematoma (n=1), Beau lines (n=1), proximal nail fold hypopigmentation (n=2), and proximal nail fold atrophy (n=2). Because the proximal nail fold in children is thinner than in adults, there may be an increased risk for nail fold hypopigmentation and atrophy in children. Therefore, a maximum ILTAC concentration of 2.5 mg/mL with 0.2 mL maximum volume per nail per session is recommended for children younger than 15 years.¹⁶

Nail Lichen Planus

Nail lichen planus (NLP) is uncommon in children, with few biopsy-proven cases documented in the literature.¹⁷ Common clinical findings are onychorrhexis, nail plate thinning, fissuring, splitting, and atrophy with koilonychia.⁵ Although pterygium development (irreversible nail matrix scarring) is uncommon in pediatric patients, NLP can be progressive and may cause irreversible destruction of the nail matrix and subsequent nail loss, warranting therapeutic intervention.¹⁸

Treatment of NLP may be difficult, as there are no options that work in all patients. Current literature supports the use of systemic corticosteroids or ILTAC for the treatment of NLP; however, recurrence rates can be high. According to an expert consensus paper on NLP treatment, ILTAC may be injected in a concentration of 2.5, 5, or 10 mg/mL according to disease severity.¹⁹ In severe or resistant cases, intramuscular (IM) triamcinolone may be considered, especially if more than 3 nails are affected. A dosage of 0.5 to 1 mg/kg/mo for at least 3 to 6 months is recommended for both children and adults, with 1 mg/kg/mo recommended in the active treatment phase (first 2–3 months).¹⁹ In a retrospective review of 5 pediatric patients with NLP treated with IM triamcinolone 0.5 mg/kg/mo, 3 patients had resolution and 2 improved with treatment.²⁰ In a prospective study of 10 children with NLP, IM triamcinolone at a dosage of 0.5 to 1 mg/kg every 30 days for 3 to 6 months resulted in resolution of nail findings in 9 patients.¹⁷ In a prospective study of 14 pediatric patients with NLP treated with 2.5 to 5 mg/mL of ILTAC, 10 achieved resolution and 3 improved.¹⁶

Intralesional triamcinolone injections may be better suited for teenagers compared to younger children who may be more apprehensive of needles. To minimize pain, it is recommended to inject ILTAC slowly at room temperature, with use of “talkesthesia” and vibration devices, 1% lidocaine, or ethyl chloride spray.¹⁸

Trachyonychia

Trachyonychia is characterized by the presence of sandpaperlike nails. It manifests with brittle thin nails with longitudinal ridging, onychoschizia, and thickened hyperkeratotic cuticles. Trachyonychia typically involves multiple nails, with a peak age of onset between 3 and 12 years.^21,22 There are 2 variants: the opaque type with rough longitudinal ridging, and the shiny variant with opalescent nails and pits that reflect light. The opaque variant is more common and is associated with psoriasis, whereas the shiny variant is less common and is associated with alopecia areata.²³ Although most cases are idiopathic, some are associated with psoriasis and alopecia areata, as previously noted, as well as atopic dermatitis (AD) and lichen planus.^22,24

Fortunately, trachyonychia does not lead to permanent nail damage or pterygium, making treatment primarily focused on addressing functional and cosmetic concerns.²⁴ Spontaneous resolution occurs in approximately 50% of patients. In a prospective study of 11 patients with idiopathic trachyonychia, there was partial improvement in 5 of 9 patients treated with topical steroids, 1 with only petrolatum, and 1 with vitamin supplements. Complete resolution was reported in 1 patient treated with topical steroids.²⁵ Because trachyonychia often is self-resolving, no treatment is required and a conservative approach is strongly recommended.²⁶ Treatment options include topical corticosteroids, tazarotene, and 5-fluorouracil. Intralesional triamcinolone, systemic cyclosporine, retinoids, systemic corticosteroids, and tofacitinib have been described in case reports, though none of these have been shown to be 100% efficacious.²⁴

Nail Lichen Striatus

Lichen striatus involving the nail is uncommon and is characterized by onycholysis, longitudinal ridging, ­splitting, and fraying, as well as what appears to be a subungual tumor. It can encompass the entire nail or may be isolated to a portion of the nail (Figure 2). Usually, a Blaschko-linear array of flesh-colored papules on the more proximal digit directly adjacent to the nail dystrophy will be seen, though nail findings can occur in ­isolation.^27-29 The underlying pathophysiology is not clear; however, one hypothesis is that a triggering event, such as trauma, induces the expression of antigens that elicit a self-limiting immune-mediated response by CD8 T lymphocytes.³⁰

Generally, nail lichen striatus spontaneously resolves in 1 to 2 years without treatment. In a prospective study of 5 patients with nail lichen striatus, the median time to resolution was 22.6 months (range, 10–30 months).³¹ Topical steroids may be used for pruritus. In one case report, a 3-year-old boy with nail lichen striatus of 4 months’ duration was treated with tacrolimus ointment 0.03% daily for 3 months.²⁸

Nail AD

Nail changes with AD may be more common in adults than children or are underreported. In a study of 777 adults with AD, nail dystrophy was present in 124 patients (16%), whereas in a study of 250 pediatric patients with AD (aged 0-2 years), nail dystrophy was present in only 4 patients.^32,33

Periungual inflammation from AD causes the nail changes.³⁴ In a cross-sectional study of 24 pediatric patients with nail dystrophy due to AD, transverse grooves (Beau lines) were present in 25% (6/24), nail pitting in 16.7% (4/24), koilonychia in 16.7% (4/24), trachyonychia in 12.5% (3/24), leukonychia in 12.5% (3/24), brachyonychia in 8.3% (2/24), melanonychia in 8.3% (2/24), onychomadesis in 8.3% (2/24), onychoschizia in 8.3% (2/24), and onycholysis in 8.3% (2/24). There was an association between disease severity and presence of toenail dystrophy (P=.03).³⁵

Topical steroids with or without occlusion can be used to treat nail changes. Although there is limited literature describing the treatment of nail AD in children, a 61-year-old man with nail changes associated with AD achieved resolution with 3 months of treatment with dupilumab.³⁶ Anecdotally, most patients will improve with usual cutaneous AD management.

INFECTIOUS NAIL DISORDERS

Viral Infections

Hand, Foot, and Mouth Disease—Hand, foot, and mouth disease (HFMD) is a common childhood viral infection caused by various enteroviruses, most commonly coxsackievirus A16, with the A6 variant causing more severe disease. Fever and painful vesicles involving the oral mucosa as well as palms and soles give the disease its name. Nail changes are common. In a prospective study involving 130 patients with laboratory-confirmed coxsackievirus CA6 serotype infection, 37% developed onychomadesis vs only 5% of 145 cases with non-CA6 enterovirus infection who developed nail findings. There was an association between CA6 infection and presence of nail changes (P<.001).³⁷

Findings ranging from transverse grooves (Beau lines) to complete nail shedding (onychomadesis)(Figure 3) may be seen.^38,39 Nail findings in HFMD are due to transient inhibition of nail growth and present approximately 3 to 6 weeks after infection.⁴⁰ Onychomadesis is seen in 30% to 68% of patients with HFMD.^37,41,42 Nail findings in HFMD spontaneously resolve with nail growth (2–3 mm per month for fingernails and 1 mm per month for toenails) and do not require specific treatment. Although the appearance of nail changes associated with HFMD can be disturbing, dermatologists can reassure children and their parents that the nails will resolve with the next cycle of growth.

Kawasaki Disease—Kawasaki disease (KD) is a vasculitis primarily affecting children and infants. Although the specific pathogen and pathophysiology is not entirely clear, clinical observations have suggested an infectious cause, most likely a virus.⁴³ In Japan, more than 15,000 cases of KD are documented annually, while approximately 4200 cases are seen in the United States.⁴⁴ In a prospective study from 1984 to 1990, 4 of 26 (15.4%) patients with KD presented with nail manifestations during the late acute phase or early convalescent phase of disease. There were no significant associations between nail dystrophy and severity of KD, such as coronary artery aneurysm.⁴⁵

Nail changes reported in children with KD include onychomadesis, onycholysis, orange-brown chromonychia, splinter hemorrhages, Beau lines, and pincer nails. In a review of nail changes associated with KD from 1980 to 2021, orange-brown transverse chromonychia, which may evolve into transverse leukonychia, was the most common nail finding reported, occurring in 17 of 31 (54.8%) patients.⁴⁴ It has been hypothesized that nail changes may result from blood flow disturbance due to the underlying vasculitis.⁴⁶ Nail changes appear several weeks after the onset of fever and are self-limited. Resolution occurs with nail growth, with no treatment required.

FUNGAL INFECTIONS

Onychomycosis

Onychomycosis is a fungal infection of the nails that occurs in 0.2% to 5.5% of pediatric patients, and its prevalence may be increasing, which may be due to environmental factors or increased rates of diabetes mellitus and obesity in the pediatric population.⁴⁷ Onychomycosis represents 15.5% of nail dystrophies in pediatric patients.⁴⁸ Some dermatologists treat presumptive onychomycosis without confirmation; however, we do not recommend that approach. Because the differential is broad and the duration of treatment is long, mycologic examination (potassium hydroxide preparation, fungal culture, polymerase chain reaction, and/or histopathology) should be obtained to confirm onychomycosis prior to initiation of antifungal management. Family members of affected individuals should be evaluated and treated, if indicated, for onychomycosis and tinea pedis, as household transmission is common.

Currently, there are 2 topical FDA-approved treatments for pediatric onychomycosis in children 6 years and older (Table 2).^49,50 There is a discussion of the need for confirmatory testing for onychomycosis in children, particularly when systemic treatment is prescribed. In a retrospective review of 269 pediatric patients with onychomycosis prescribed terbinafine, 53.5% (n=144) underwent laboratory monitoring of liver function and complete blood cell counts, and 12.5% had grade 1 laboratory abnormalities either prior to (12/144 [8.3%]) or during (6/144 [4.2%]) therapy.⁵¹ Baseline transaminase monitoring is recommended, though subsequent routine laboratory monitoring in healthy children may have limited utility with associated increased costs, incidental findings, and patient discomfort and likely is not needed.⁵¹

Pediatric onychomycosis responds better to topical therapy than adult disease, and pediatric patients do not always require systemic treatment.⁵² Ciclopirox is not FDA approved for the treatment of pediatric onychomycosis, but in a 32-week clinical trial of ciclopirox lacquer 8% use in 40 patients, 77% (27/35) of treated patients achieved mycologic cure. Overall, 71% of treated patients (25/35) vs 22% (2/9) of controls achieved efficacy (defined as investigator global assessment score of 2 or lower).⁵² In an open-label, single-arm clinical trial assessing tavaborole solution 5% applied once daily for 48 weeks for the treatment of toenail onychomycosis in pediatric patients (aged 6–17 years), 36.2% (20/55) of patients achieved mycologic cure, and 8.5% (5/55) achieved complete cure at week 52 with mild or minimal adverse effects.⁵³ In an open-label, phase 4 study of the safety and efficacy of efinaconazole solution 10% applied once daily for 48 weeks in pediatric patients (aged 6 to 16 years) (n=60), 65% (35/60) achieved mycologic cure, 42% (25/60) achieved clinical cure, and 40% (24/60) achieved complete cure at 52 weeks. The most common adverse effects of efina­conazole were local and included ingrown toenail (1/60), application-site dermatitis (1/60), application-site vesicles (1/60), and application-site pain (1/60).⁵⁴

In a systematic review of systemic antifungals for onychomycosis in 151 pediatric patients, itraconazole, fluconazole, griseofulvin, and terbinafine resulted in complete cure rates similar to those of the adult population, with excellent safety profiles.⁵⁵ Depending on the situation, initiation of treatment with topical medications followed by addition of systemic antifungal agents only if needed may be an appropriate course of action.

BACTERIAL INFECTIONS

Acute Paronychia

Acute paronychia is a nail-fold infection that develops after the protective nail barrier has been compromised.⁵⁶ In children, thumb-sucking, nail-biting, frequent oral manipulation of the digits, and poor skin hygiene are risk factors. Acute paronychia also may develop in association with congenital malalignment of the great toenails.⁵⁷

Clinical manifestations include localized pain, erythema, and nail fold edema (Figure 4). Purulent material and abscess formation may ensue. Staphylococcus aureus as well as methicillin-resistant S aureus and Streptococcus pyogenes are classically the most common causes of acute paronychia. Treatment of paronychia is based on severity. In mild cases, warm soaks with topical antibiotics are indicated. Oral antibiotics should be prescribed for more severe presentations. If there is no improvement after 48 hours, surgical drainage is required to facilitate healing.⁵⁶

FINAL THOUGHTS

Inflammatory and infectious nail disorders in children are relatively common and may impact the physical and emotional well-being of young patients. By understanding the distinctive features of these nail disorders in pediatric patients, dermatologists can provide anticipatory guidance and informed treatment options to children and their parents. Further research is needed to expand our understanding of pediatric nail disorders and create targeted therapeutic interventions, particularly for NLP and psoriasis.

Practice Gap

Lichen planus (LP)—a chronic inflammatory disorder affecting the nails—is prevalent in 10% to 15% of patients and is more common in the fingernails than toenails. Clinical manifestation includes longitudinal ridges, nail plate atrophy, and splitting, which all contribute to cosmetic disfigurement and difficulty with functionality. Quality of life and daily activities may be impacted profoundly.¹ First-line therapies include intralesional and systemic corticosteroids; however, efficacy is limited and recurrence is common.^1,2 Lichen planus is one of the few conditions that may cause permanent and debilitating nail loss.

Tools

A resin nail can be used to improve cosmetic appearance and functionality in patients with recalcitrant nail LP. The composite resin creates a flexible nonporous nail and allows the underlying natural nail to grow. Application of resin nails has been used for toenail onychodystrophies to improve cosmesis and functionality but has not been reported for fingernails. The resin typically lasts 6 to 8 weeks on toenails.

The Technique

Application of a resin nail involves several steps (see video online). First, the affected nail should be debrided and a bonding agent applied. Next, multiple layers of resin are applied until the patient’s desired thickness is achieved (typically 2 layers), followed by a sealing agent. Finally, the nail is cured with UV light. We recommend applying sunscreen to the hand(s) prior to curing with UV light. The liquid resin allows the nail to be customized to the patient’s desired length and shape. The overall procedure takes approximately 20 minutes for a single nail.

We applied resin nail to the thumbnail of a 46-year-old woman with recalcitrant isolated nail LP of 7 years’ duration (Figure). She previously had difficulties performing everyday activities, and the resin improved her functionality. She also was pleased with the cosmetic appearance. After 2 weeks, the resin started falling off with corresponding natural nail growth. The patient denied any adverse events.

Practice Implications

Resin nail application may serve as a temporary solution to improve cosmesis and functionality in patients with recalcitrant nail LP. As shown in our patient, the resin may fall off faster on the fingernails than the toenails, likely because of the faster growth rate of fingernails and more frequent exposure from daily activities. Further studies of resin nail application for the fingernails are needed to establish duration in patients with varying levels of activity (eg, washing dishes, woodworking).

Because the resin nail may be removed easily at any time, resin nail application does not interfere with treatments such as intralesional steroid injections. For patients using a topical medication regimen, the resin nail may be applied slightly distal to the cuticle so that the medication can still be applied by the proximal nail fold of the underlying natural nail.

The resin nail should be kept short and removed after 2 to 4 weeks for the fingernails and 6 to 8 weeks for the toenails to examine the underlying natural nail. Patients may go about their daily activities with the resin nail, including applying nail polish to the resin nail, bathing, and swimming. Resin nail application may complement medical treatments and improve quality of life for patients with nail LP.

Practice Gap

Lichen planus (LP)—a chronic inflammatory disorder affecting the nails—is prevalent in 10% to 15% of patients and is more common in the fingernails than toenails. Clinical manifestation includes longitudinal ridges, nail plate atrophy, and splitting, which all contribute to cosmetic disfigurement and difficulty with functionality. Quality of life and daily activities may be impacted profoundly.¹ First-line therapies include intralesional and systemic corticosteroids; however, efficacy is limited and recurrence is common.^1,2 Lichen planus is one of the few conditions that may cause permanent and debilitating nail loss.

Tools

A resin nail can be used to improve cosmetic appearance and functionality in patients with recalcitrant nail LP. The composite resin creates a flexible nonporous nail and allows the underlying natural nail to grow. Application of resin nails has been used for toenail onychodystrophies to improve cosmesis and functionality but has not been reported for fingernails. The resin typically lasts 6 to 8 weeks on toenails.

The Technique

Application of a resin nail involves several steps (see video online). First, the affected nail should be debrided and a bonding agent applied. Next, multiple layers of resin are applied until the patient’s desired thickness is achieved (typically 2 layers), followed by a sealing agent. Finally, the nail is cured with UV light. We recommend applying sunscreen to the hand(s) prior to curing with UV light. The liquid resin allows the nail to be customized to the patient’s desired length and shape. The overall procedure takes approximately 20 minutes for a single nail.

We applied resin nail to the thumbnail of a 46-year-old woman with recalcitrant isolated nail LP of 7 years’ duration (Figure). She previously had difficulties performing everyday activities, and the resin improved her functionality. She also was pleased with the cosmetic appearance. After 2 weeks, the resin started falling off with corresponding natural nail growth. The patient denied any adverse events.

Practice Implications

Resin nail application may serve as a temporary solution to improve cosmesis and functionality in patients with recalcitrant nail LP. As shown in our patient, the resin may fall off faster on the fingernails than the toenails, likely because of the faster growth rate of fingernails and more frequent exposure from daily activities. Further studies of resin nail application for the fingernails are needed to establish duration in patients with varying levels of activity (eg, washing dishes, woodworking).

Because the resin nail may be removed easily at any time, resin nail application does not interfere with treatments such as intralesional steroid injections. For patients using a topical medication regimen, the resin nail may be applied slightly distal to the cuticle so that the medication can still be applied by the proximal nail fold of the underlying natural nail.

The resin nail should be kept short and removed after 2 to 4 weeks for the fingernails and 6 to 8 weeks for the toenails to examine the underlying natural nail. Patients may go about their daily activities with the resin nail, including applying nail polish to the resin nail, bathing, and swimming. Resin nail application may complement medical treatments and improve quality of life for patients with nail LP.

Practice Gap

Lichen planus (LP)—a chronic inflammatory disorder affecting the nails—is prevalent in 10% to 15% of patients and is more common in the fingernails than toenails. Clinical manifestation includes longitudinal ridges, nail plate atrophy, and splitting, which all contribute to cosmetic disfigurement and difficulty with functionality. Quality of life and daily activities may be impacted profoundly.¹ First-line therapies include intralesional and systemic corticosteroids; however, efficacy is limited and recurrence is common.^1,2 Lichen planus is one of the few conditions that may cause permanent and debilitating nail loss.

Tools

A resin nail can be used to improve cosmetic appearance and functionality in patients with recalcitrant nail LP. The composite resin creates a flexible nonporous nail and allows the underlying natural nail to grow. Application of resin nails has been used for toenail onychodystrophies to improve cosmesis and functionality but has not been reported for fingernails. The resin typically lasts 6 to 8 weeks on toenails.

The Technique

Application of a resin nail involves several steps (see video online). First, the affected nail should be debrided and a bonding agent applied. Next, multiple layers of resin are applied until the patient’s desired thickness is achieved (typically 2 layers), followed by a sealing agent. Finally, the nail is cured with UV light. We recommend applying sunscreen to the hand(s) prior to curing with UV light. The liquid resin allows the nail to be customized to the patient’s desired length and shape. The overall procedure takes approximately 20 minutes for a single nail.

We applied resin nail to the thumbnail of a 46-year-old woman with recalcitrant isolated nail LP of 7 years’ duration (Figure). She previously had difficulties performing everyday activities, and the resin improved her functionality. She also was pleased with the cosmetic appearance. After 2 weeks, the resin started falling off with corresponding natural nail growth. The patient denied any adverse events.

Practice Implications

Resin nail application may serve as a temporary solution to improve cosmesis and functionality in patients with recalcitrant nail LP. As shown in our patient, the resin may fall off faster on the fingernails than the toenails, likely because of the faster growth rate of fingernails and more frequent exposure from daily activities. Further studies of resin nail application for the fingernails are needed to establish duration in patients with varying levels of activity (eg, washing dishes, woodworking).

Because the resin nail may be removed easily at any time, resin nail application does not interfere with treatments such as intralesional steroid injections. For patients using a topical medication regimen, the resin nail may be applied slightly distal to the cuticle so that the medication can still be applied by the proximal nail fold of the underlying natural nail.

The resin nail should be kept short and removed after 2 to 4 weeks for the fingernails and 6 to 8 weeks for the toenails to examine the underlying natural nail. Patients may go about their daily activities with the resin nail, including applying nail polish to the resin nail, bathing, and swimming. Resin nail application may complement medical treatments and improve quality of life for patients with nail LP.

To the Editor:

Phototherapy regularly is utilized in the outpatient setting to address various skin pathologies, including atopic dermatitis, psoriasis, pruritus, vitiligo, and mycosis fungoides.^1,2 Phototherapy is broadly defined by the measured administration of nonionizing radiation within the UV range including wavelengths within the UVA (eg, psoralen sensitizer plus UVA-1) and UVB (eg, broadband UVB, narrowband UVB) spectrums.^1,3 Generally, the mechanism of action is derived from effects on inflammatory components of cutaneous disorders and the induction of apoptosis, both precipitating numerous downstream events.⁴

From 2015 to 2018, there were more than 1.3 million outpatient phototherapy visits in the United States, with the most common procedural indications being dermatitis not otherwise specified, atopic dermatitis, and pruritus.⁵ From 2000 to 2015, the quantity of phototherapy services billed to Medicare trended upwards by an average of 5% per year, increasing from 334,670 in the year 2000 to 692,093 in 2015.⁶ Therefore, an illustration of associated costs would be beneficial. Additionally, because total cost and physician reimbursement fluctuate from year to year, studies demonstrating overall trends can inform both US policymakers and physicians. There is a paucity of research on geographical trends for procedural reimbursements in dermatology for phototherapy. Understanding geographic trends of reimbursement could duly serve to optimize dermatologist practice patterns involving access to viable and quality care for patients seeking treatment as well as draw health policymakers’ attention to striking adjustments in physician fees. Therefore, in this study we aimed to illustrate the most recent regional payment trends in phototherapy procedures for Medicare B patients.

We queried the Centers for Medicare & Medicaid Services Medicare Physician Fee Schedule (MPFS) database (https://www.cms.gov/medicare/payment/fee-schedules/physician/lookup-tool) for the years 2010 to 2023 for Current Procedural Terminology (CPT) codes common to phototherapy procedures: actinotherapy (96900); photochemotherapy by Goeckerman treatment or using petrolatum and UVB (96910); photochemotherapy using psoralen plus UVA (96912); and photochemotherapy of severe dermatoses requiring a minimum of 4 hours of care under direct physician supervision (96913). Nonfacility prices for these procedures were analyzed. For 2010, due to midyear alterations to Medicare reimbursement (owed to bills HR 3962 and HR 4872), the mean price data of MPFS files 2010A and 2010B were used. All dollar values were converted to January 2023 US dollars using corresponding consumer price index inflation data. The Medicare Administrative Contractors were used to group state pricing information by region in accordance with established US Census Bureau subdivisions (https://www.census.gov/programs-surveys/economic-census/guidance-geographies/levels.html). Weighted percentage change in reimbursement rate was calculated using physician (MD or DO) utilization (procedure volume) data available in the 2020 Physician and Other Practitioners Public Use File (https://data.cms.gov/provider-summary-by-type-of-service/medicare-physician-other-practitioners/medicare-physician-other-practitioners-by-provider-and-service). All descriptive statistics and visualization were generated using R software (v4.2.2)(R Development Core Team).

Table 1 provides physician utilization data and the corresponding number of Part B beneficiaries for phototherapy procedures in 2020. There were 65,045 services of actinotherapy provided to a total of 6855 unique Part B beneficiaries, 173,979 services of photochemotherapy by Goeckerman treatment or using petrolatum and UVB provided to 13,122 unique Part B beneficiaries, 2524 services of photochemotherapy using psoralen plus UVA provided to a total of 357 unique Part B beneficiaries, and 37 services of photochemotherapy of severe dermatoses requiring a minimum of 4 hours of care under direct physician supervision provided to a total of 27 unique Part B beneficiaries.

On average (unweighted), phototherapy reimbursement rates in the North increased by 0.68% between 2010 and 2023 (Table 2). After weighting for 2020 physician utilization, the average change in reimbursement rate was +19.37%. During this time period, CPT code 96910 reported the greatest adjusted increase in reimbursement (+31.45%)($98.12 to $128.98; compound annual growth rate [CAGR], +0.0213), and CPT code 96912 reported the greatest adjusted decrease in reimbursement (−12.76%)($126.09 to $109.97; CAGR, −0.0105). For CPT code 96900, the reported adjusted decrease in reimbursement was −11.68% ($30.21 to $26.68; CAGR, −0.0095), and for CPT code 96913, the reported adjusted decrease in reimbursement was −4.27% ($174.03 to $166.60; CAGR, −0.0034).

On average (unweighted), phototherapy reimbursement rates in the Midwest increased by 8.40% between 2010 and 2023 (Table 3). After weighting for 2020 physician utilization, the average change in reimbursement rate was +28.53%. During this time period, CPT code 96910 reported the greatest adjusted change in reimbursement (+41.48%)($80.42 to $113.78; CAGR, +0.0270), and CPT code 96912 reported the greatest adjusted decrease in reimbursement (−6.14%)($103.28 to $97.03; CAGR, −0.0049). For CPT code 96900, the reported adjusted decrease in reimbursement was −4.73% ($24.69 to $23.52; CAGR, −0.0037), and for CPT code 96913, the reported adjusted increase in reimbursement was +2.99% ($142.72 to $146.99; CAGR, +0.0023).

On average (unweighted), phototherapy reimbursement rates in the South decreased by 2.62% between 2010 and 2023 (Table 4). After weighting for 2020 physician utilization, the average change in reimbursement rate was +15.41%. During this time period, CPT code 96910 reported the greatest adjusted change in reimbursement (+27.26%)($90.40 to $115.04 USD; CAGR, +0.0187), and CPT code 96912 reported the greatest adjusted decrease in reimbursement (−15.50%)($116.08 to $98.09; CAGR, −0.0129). For CPT code 96900, the reported adjusted decrease in reimbursement was −15.06% ($28.02 to $23.80; CAGR, −0.0125), and for CPT code 96913, the reported adjusted decrease in reimbursement was −7.19% ($160.11 to $148.61; CAGR, −0.0057).

On average (unweighted), phototherapy reimbursement rates in the West increased by 27.53% between 2010 and 2023 (Table 5). After weighting for 2020 physician utilization, the average change in reimbursement rate was +51.16%. Reimbursement for all analyzed procedures increased in the western United States. During this time period, CPT code 96910 reported the greatest adjusted increase in reimbursement (+66.56%)($80.84 to $134.65; CAGR, +0.0400), and CPT code 96912 reported the lowest adjusted increase in reimbursement (+10.64%)($103.88 to $114.93; CAGR, +0.0078). For CPT code 96900, the reported adjusted increase in reimbursement was 11.54% ($24.88 to $27.75; CAGR, +0.0084), and for CPT code 96913, the reported adjusted increase in reimbursement was 21.38% ($143.39 to $174.04; CAGR, +0.0150).

In this study evaluating geographical payment trends for phototherapy from 2010 to 2023, we demonstrated regional inconsistency in mean inflation-adjusted Medicare reimbursement rates. We found that all phototherapy procedures had increased reimbursement in the western United States, whereas all other regions reported cuts in reimbursement rates for at least half of the analyzed procedures. After adjusting for procedure utilization by physicians, weighted mean reimbursement for phototherapy increased in all US regions.

In a cross-sectional study that explored trends in the geographic distribution of dermatologists from 2012 to 2017, dermatologists in the northeastern and western United States were more likely to be located in higher-income zip codes, whereas dermatologists in the southern United States were more likely to be located in lower-income zip codes,⁷ suggesting that payment rate changes are not concordant with cost of living. Additionally, Lauck and colleagues⁸ observed that 75% of the top 20 most common procedures performed by dermatologists had decreased reimbursement (mean change, −10.8%) from 2011 to 2021. Other studies on Medicare reimbursement trends over the last 2 decades have reported major decreases within other specialties, suggesting that declining Medicare reimbursements are not unique to dermatology.^9,10 It is critical to monitor these developments, as the Centers for Medicare & Medicaid Services emphasized health care policy changes aimed at increasing reimbursements for evaluation and management services with compensatory payment cuts in billing for procedural services.¹¹

Mazmudar et al¹² previously reported a mean reimbursement decrease of −6.6% for laser/phototherapy procedures between 2007 and 2021, but these data did not include the heavily utilized Goeckerman treatment. Changes in reimbursement pose major ramifications for dermatologists—for practice size, scope, and longevity—as rates influence changes in commercial insurance reimbursements.¹³ Medicare plays a major role in the US health care system as the second largest expenditure¹⁴; indeed, between 2000 and 2015, Part B billing volume for phototherapy procedures increased 5% annually. However, phototherapy remains inaccessible in many locations due to unequal regional distribution of phototherapy clinics.⁶ Moreover, home phototherapy units are not yet widely utilized because of safety and efficacy concerns, lack of physician oversight, and difficulty obtaining insurance coverage.¹⁵ Acknowledgment and consideration of these geographical trends may persuasively allow policymakers, hospitals, and physicians to facilitate cost-effective phototherapy reimbursements that ensure continued access to quality and sustainable dermatologic care in the United States that tailor to regional needs.

In sum, this analysis reveals regional trends in Part B physician reimbursement for phototherapy procedures, with all US regions reporting a mean increase in phototherapy reimbursement after adjusting for utilization, albeit to varying degrees. Mean reimbursement for photochemotherapy by Goeckerman treatment or using petrolatum and UVB increased most among phototherapy procedures. Mean reimbursement for both actinotherapy and photochemotherapy using psoralen plus UVA decreased in all regions except the western United States.

Limitations include the restriction to Part B MPFS and the reliance on single-year (2020) physician utilization data to compute weighted changes in average reimbursement across a multiyear range, effectively restricting sweeping conclusions. Still, this study puts forth actionable insights for dermatologists and policymakers alike to appreciate and consider.

To the Editor:

Phototherapy regularly is utilized in the outpatient setting to address various skin pathologies, including atopic dermatitis, psoriasis, pruritus, vitiligo, and mycosis fungoides.^1,2 Phototherapy is broadly defined by the measured administration of nonionizing radiation within the UV range including wavelengths within the UVA (eg, psoralen sensitizer plus UVA-1) and UVB (eg, broadband UVB, narrowband UVB) spectrums.^1,3 Generally, the mechanism of action is derived from effects on inflammatory components of cutaneous disorders and the induction of apoptosis, both precipitating numerous downstream events.⁴

From 2015 to 2018, there were more than 1.3 million outpatient phototherapy visits in the United States, with the most common procedural indications being dermatitis not otherwise specified, atopic dermatitis, and pruritus.⁵ From 2000 to 2015, the quantity of phototherapy services billed to Medicare trended upwards by an average of 5% per year, increasing from 334,670 in the year 2000 to 692,093 in 2015.⁶ Therefore, an illustration of associated costs would be beneficial. Additionally, because total cost and physician reimbursement fluctuate from year to year, studies demonstrating overall trends can inform both US policymakers and physicians. There is a paucity of research on geographical trends for procedural reimbursements in dermatology for phototherapy. Understanding geographic trends of reimbursement could duly serve to optimize dermatologist practice patterns involving access to viable and quality care for patients seeking treatment as well as draw health policymakers’ attention to striking adjustments in physician fees. Therefore, in this study we aimed to illustrate the most recent regional payment trends in phototherapy procedures for Medicare B patients.

We queried the Centers for Medicare & Medicaid Services Medicare Physician Fee Schedule (MPFS) database (https://www.cms.gov/medicare/payment/fee-schedules/physician/lookup-tool) for the years 2010 to 2023 for Current Procedural Terminology (CPT) codes common to phototherapy procedures: actinotherapy (96900); photochemotherapy by Goeckerman treatment or using petrolatum and UVB (96910); photochemotherapy using psoralen plus UVA (96912); and photochemotherapy of severe dermatoses requiring a minimum of 4 hours of care under direct physician supervision (96913). Nonfacility prices for these procedures were analyzed. For 2010, due to midyear alterations to Medicare reimbursement (owed to bills HR 3962 and HR 4872), the mean price data of MPFS files 2010A and 2010B were used. All dollar values were converted to January 2023 US dollars using corresponding consumer price index inflation data. The Medicare Administrative Contractors were used to group state pricing information by region in accordance with established US Census Bureau subdivisions (https://www.census.gov/programs-surveys/economic-census/guidance-geographies/levels.html). Weighted percentage change in reimbursement rate was calculated using physician (MD or DO) utilization (procedure volume) data available in the 2020 Physician and Other Practitioners Public Use File (https://data.cms.gov/provider-summary-by-type-of-service/medicare-physician-other-practitioners/medicare-physician-other-practitioners-by-provider-and-service). All descriptive statistics and visualization were generated using R software (v4.2.2)(R Development Core Team).

Table 1 provides physician utilization data and the corresponding number of Part B beneficiaries for phototherapy procedures in 2020. There were 65,045 services of actinotherapy provided to a total of 6855 unique Part B beneficiaries, 173,979 services of photochemotherapy by Goeckerman treatment or using petrolatum and UVB provided to 13,122 unique Part B beneficiaries, 2524 services of photochemotherapy using psoralen plus UVA provided to a total of 357 unique Part B beneficiaries, and 37 services of photochemotherapy of severe dermatoses requiring a minimum of 4 hours of care under direct physician supervision provided to a total of 27 unique Part B beneficiaries.

On average (unweighted), phototherapy reimbursement rates in the North increased by 0.68% between 2010 and 2023 (Table 2). After weighting for 2020 physician utilization, the average change in reimbursement rate was +19.37%. During this time period, CPT code 96910 reported the greatest adjusted increase in reimbursement (+31.45%)($98.12 to $128.98; compound annual growth rate [CAGR], +0.0213), and CPT code 96912 reported the greatest adjusted decrease in reimbursement (−12.76%)($126.09 to $109.97; CAGR, −0.0105). For CPT code 96900, the reported adjusted decrease in reimbursement was −11.68% ($30.21 to $26.68; CAGR, −0.0095), and for CPT code 96913, the reported adjusted decrease in reimbursement was −4.27% ($174.03 to $166.60; CAGR, −0.0034).

On average (unweighted), phototherapy reimbursement rates in the Midwest increased by 8.40% between 2010 and 2023 (Table 3). After weighting for 2020 physician utilization, the average change in reimbursement rate was +28.53%. During this time period, CPT code 96910 reported the greatest adjusted change in reimbursement (+41.48%)($80.42 to $113.78; CAGR, +0.0270), and CPT code 96912 reported the greatest adjusted decrease in reimbursement (−6.14%)($103.28 to $97.03; CAGR, −0.0049). For CPT code 96900, the reported adjusted decrease in reimbursement was −4.73% ($24.69 to $23.52; CAGR, −0.0037), and for CPT code 96913, the reported adjusted increase in reimbursement was +2.99% ($142.72 to $146.99; CAGR, +0.0023).

On average (unweighted), phototherapy reimbursement rates in the South decreased by 2.62% between 2010 and 2023 (Table 4). After weighting for 2020 physician utilization, the average change in reimbursement rate was +15.41%. During this time period, CPT code 96910 reported the greatest adjusted change in reimbursement (+27.26%)($90.40 to $115.04 USD; CAGR, +0.0187), and CPT code 96912 reported the greatest adjusted decrease in reimbursement (−15.50%)($116.08 to $98.09; CAGR, −0.0129). For CPT code 96900, the reported adjusted decrease in reimbursement was −15.06% ($28.02 to $23.80; CAGR, −0.0125), and for CPT code 96913, the reported adjusted decrease in reimbursement was −7.19% ($160.11 to $148.61; CAGR, −0.0057).

On average (unweighted), phototherapy reimbursement rates in the West increased by 27.53% between 2010 and 2023 (Table 5). After weighting for 2020 physician utilization, the average change in reimbursement rate was +51.16%. Reimbursement for all analyzed procedures increased in the western United States. During this time period, CPT code 96910 reported the greatest adjusted increase in reimbursement (+66.56%)($80.84 to $134.65; CAGR, +0.0400), and CPT code 96912 reported the lowest adjusted increase in reimbursement (+10.64%)($103.88 to $114.93; CAGR, +0.0078). For CPT code 96900, the reported adjusted increase in reimbursement was 11.54% ($24.88 to $27.75; CAGR, +0.0084), and for CPT code 96913, the reported adjusted increase in reimbursement was 21.38% ($143.39 to $174.04; CAGR, +0.0150).

In this study evaluating geographical payment trends for phototherapy from 2010 to 2023, we demonstrated regional inconsistency in mean inflation-adjusted Medicare reimbursement rates. We found that all phototherapy procedures had increased reimbursement in the western United States, whereas all other regions reported cuts in reimbursement rates for at least half of the analyzed procedures. After adjusting for procedure utilization by physicians, weighted mean reimbursement for phototherapy increased in all US regions.

In a cross-sectional study that explored trends in the geographic distribution of dermatologists from 2012 to 2017, dermatologists in the northeastern and western United States were more likely to be located in higher-income zip codes, whereas dermatologists in the southern United States were more likely to be located in lower-income zip codes,⁷ suggesting that payment rate changes are not concordant with cost of living. Additionally, Lauck and colleagues⁸ observed that 75% of the top 20 most common procedures performed by dermatologists had decreased reimbursement (mean change, −10.8%) from 2011 to 2021. Other studies on Medicare reimbursement trends over the last 2 decades have reported major decreases within other specialties, suggesting that declining Medicare reimbursements are not unique to dermatology.^9,10 It is critical to monitor these developments, as the Centers for Medicare & Medicaid Services emphasized health care policy changes aimed at increasing reimbursements for evaluation and management services with compensatory payment cuts in billing for procedural services.¹¹

Mazmudar et al¹² previously reported a mean reimbursement decrease of −6.6% for laser/phototherapy procedures between 2007 and 2021, but these data did not include the heavily utilized Goeckerman treatment. Changes in reimbursement pose major ramifications for dermatologists—for practice size, scope, and longevity—as rates influence changes in commercial insurance reimbursements.¹³ Medicare plays a major role in the US health care system as the second largest expenditure¹⁴; indeed, between 2000 and 2015, Part B billing volume for phototherapy procedures increased 5% annually. However, phototherapy remains inaccessible in many locations due to unequal regional distribution of phototherapy clinics.⁶ Moreover, home phototherapy units are not yet widely utilized because of safety and efficacy concerns, lack of physician oversight, and difficulty obtaining insurance coverage.¹⁵ Acknowledgment and consideration of these geographical trends may persuasively allow policymakers, hospitals, and physicians to facilitate cost-effective phototherapy reimbursements that ensure continued access to quality and sustainable dermatologic care in the United States that tailor to regional needs.

In sum, this analysis reveals regional trends in Part B physician reimbursement for phototherapy procedures, with all US regions reporting a mean increase in phototherapy reimbursement after adjusting for utilization, albeit to varying degrees. Mean reimbursement for photochemotherapy by Goeckerman treatment or using petrolatum and UVB increased most among phototherapy procedures. Mean reimbursement for both actinotherapy and photochemotherapy using psoralen plus UVA decreased in all regions except the western United States.

Limitations include the restriction to Part B MPFS and the reliance on single-year (2020) physician utilization data to compute weighted changes in average reimbursement across a multiyear range, effectively restricting sweeping conclusions. Still, this study puts forth actionable insights for dermatologists and policymakers alike to appreciate and consider.

To the Editor:

Phototherapy regularly is utilized in the outpatient setting to address various skin pathologies, including atopic dermatitis, psoriasis, pruritus, vitiligo, and mycosis fungoides.^1,2 Phototherapy is broadly defined by the measured administration of nonionizing radiation within the UV range including wavelengths within the UVA (eg, psoralen sensitizer plus UVA-1) and UVB (eg, broadband UVB, narrowband UVB) spectrums.^1,3 Generally, the mechanism of action is derived from effects on inflammatory components of cutaneous disorders and the induction of apoptosis, both precipitating numerous downstream events.⁴

From 2015 to 2018, there were more than 1.3 million outpatient phototherapy visits in the United States, with the most common procedural indications being dermatitis not otherwise specified, atopic dermatitis, and pruritus.⁵ From 2000 to 2015, the quantity of phototherapy services billed to Medicare trended upwards by an average of 5% per year, increasing from 334,670 in the year 2000 to 692,093 in 2015.⁶ Therefore, an illustration of associated costs would be beneficial. Additionally, because total cost and physician reimbursement fluctuate from year to year, studies demonstrating overall trends can inform both US policymakers and physicians. There is a paucity of research on geographical trends for procedural reimbursements in dermatology for phototherapy. Understanding geographic trends of reimbursement could duly serve to optimize dermatologist practice patterns involving access to viable and quality care for patients seeking treatment as well as draw health policymakers’ attention to striking adjustments in physician fees. Therefore, in this study we aimed to illustrate the most recent regional payment trends in phototherapy procedures for Medicare B patients.

We queried the Centers for Medicare & Medicaid Services Medicare Physician Fee Schedule (MPFS) database (https://www.cms.gov/medicare/payment/fee-schedules/physician/lookup-tool) for the years 2010 to 2023 for Current Procedural Terminology (CPT) codes common to phototherapy procedures: actinotherapy (96900); photochemotherapy by Goeckerman treatment or using petrolatum and UVB (96910); photochemotherapy using psoralen plus UVA (96912); and photochemotherapy of severe dermatoses requiring a minimum of 4 hours of care under direct physician supervision (96913). Nonfacility prices for these procedures were analyzed. For 2010, due to midyear alterations to Medicare reimbursement (owed to bills HR 3962 and HR 4872), the mean price data of MPFS files 2010A and 2010B were used. All dollar values were converted to January 2023 US dollars using corresponding consumer price index inflation data. The Medicare Administrative Contractors were used to group state pricing information by region in accordance with established US Census Bureau subdivisions (https://www.census.gov/programs-surveys/economic-census/guidance-geographies/levels.html). Weighted percentage change in reimbursement rate was calculated using physician (MD or DO) utilization (procedure volume) data available in the 2020 Physician and Other Practitioners Public Use File (https://data.cms.gov/provider-summary-by-type-of-service/medicare-physician-other-practitioners/medicare-physician-other-practitioners-by-provider-and-service). All descriptive statistics and visualization were generated using R software (v4.2.2)(R Development Core Team).

Table 1 provides physician utilization data and the corresponding number of Part B beneficiaries for phototherapy procedures in 2020. There were 65,045 services of actinotherapy provided to a total of 6855 unique Part B beneficiaries, 173,979 services of photochemotherapy by Goeckerman treatment or using petrolatum and UVB provided to 13,122 unique Part B beneficiaries, 2524 services of photochemotherapy using psoralen plus UVA provided to a total of 357 unique Part B beneficiaries, and 37 services of photochemotherapy of severe dermatoses requiring a minimum of 4 hours of care under direct physician supervision provided to a total of 27 unique Part B beneficiaries.

On average (unweighted), phototherapy reimbursement rates in the North increased by 0.68% between 2010 and 2023 (Table 2). After weighting for 2020 physician utilization, the average change in reimbursement rate was +19.37%. During this time period, CPT code 96910 reported the greatest adjusted increase in reimbursement (+31.45%)($98.12 to $128.98; compound annual growth rate [CAGR], +0.0213), and CPT code 96912 reported the greatest adjusted decrease in reimbursement (−12.76%)($126.09 to $109.97; CAGR, −0.0105). For CPT code 96900, the reported adjusted decrease in reimbursement was −11.68% ($30.21 to $26.68; CAGR, −0.0095), and for CPT code 96913, the reported adjusted decrease in reimbursement was −4.27% ($174.03 to $166.60; CAGR, −0.0034).

On average (unweighted), phototherapy reimbursement rates in the Midwest increased by 8.40% between 2010 and 2023 (Table 3). After weighting for 2020 physician utilization, the average change in reimbursement rate was +28.53%. During this time period, CPT code 96910 reported the greatest adjusted change in reimbursement (+41.48%)($80.42 to $113.78; CAGR, +0.0270), and CPT code 96912 reported the greatest adjusted decrease in reimbursement (−6.14%)($103.28 to $97.03; CAGR, −0.0049). For CPT code 96900, the reported adjusted decrease in reimbursement was −4.73% ($24.69 to $23.52; CAGR, −0.0037), and for CPT code 96913, the reported adjusted increase in reimbursement was +2.99% ($142.72 to $146.99; CAGR, +0.0023).

On average (unweighted), phototherapy reimbursement rates in the South decreased by 2.62% between 2010 and 2023 (Table 4). After weighting for 2020 physician utilization, the average change in reimbursement rate was +15.41%. During this time period, CPT code 96910 reported the greatest adjusted change in reimbursement (+27.26%)($90.40 to $115.04 USD; CAGR, +0.0187), and CPT code 96912 reported the greatest adjusted decrease in reimbursement (−15.50%)($116.08 to $98.09; CAGR, −0.0129). For CPT code 96900, the reported adjusted decrease in reimbursement was −15.06% ($28.02 to $23.80; CAGR, −0.0125), and for CPT code 96913, the reported adjusted decrease in reimbursement was −7.19% ($160.11 to $148.61; CAGR, −0.0057).

On average (unweighted), phototherapy reimbursement rates in the West increased by 27.53% between 2010 and 2023 (Table 5). After weighting for 2020 physician utilization, the average change in reimbursement rate was +51.16%. Reimbursement for all analyzed procedures increased in the western United States. During this time period, CPT code 96910 reported the greatest adjusted increase in reimbursement (+66.56%)($80.84 to $134.65; CAGR, +0.0400), and CPT code 96912 reported the lowest adjusted increase in reimbursement (+10.64%)($103.88 to $114.93; CAGR, +0.0078). For CPT code 96900, the reported adjusted increase in reimbursement was 11.54% ($24.88 to $27.75; CAGR, +0.0084), and for CPT code 96913, the reported adjusted increase in reimbursement was 21.38% ($143.39 to $174.04; CAGR, +0.0150).

In this study evaluating geographical payment trends for phototherapy from 2010 to 2023, we demonstrated regional inconsistency in mean inflation-adjusted Medicare reimbursement rates. We found that all phototherapy procedures had increased reimbursement in the western United States, whereas all other regions reported cuts in reimbursement rates for at least half of the analyzed procedures. After adjusting for procedure utilization by physicians, weighted mean reimbursement for phototherapy increased in all US regions.

In a cross-sectional study that explored trends in the geographic distribution of dermatologists from 2012 to 2017, dermatologists in the northeastern and western United States were more likely to be located in higher-income zip codes, whereas dermatologists in the southern United States were more likely to be located in lower-income zip codes,⁷ suggesting that payment rate changes are not concordant with cost of living. Additionally, Lauck and colleagues⁸ observed that 75% of the top 20 most common procedures performed by dermatologists had decreased reimbursement (mean change, −10.8%) from 2011 to 2021. Other studies on Medicare reimbursement trends over the last 2 decades have reported major decreases within other specialties, suggesting that declining Medicare reimbursements are not unique to dermatology.^9,10 It is critical to monitor these developments, as the Centers for Medicare & Medicaid Services emphasized health care policy changes aimed at increasing reimbursements for evaluation and management services with compensatory payment cuts in billing for procedural services.¹¹

Mazmudar et al¹² previously reported a mean reimbursement decrease of −6.6% for laser/phototherapy procedures between 2007 and 2021, but these data did not include the heavily utilized Goeckerman treatment. Changes in reimbursement pose major ramifications for dermatologists—for practice size, scope, and longevity—as rates influence changes in commercial insurance reimbursements.¹³ Medicare plays a major role in the US health care system as the second largest expenditure¹⁴; indeed, between 2000 and 2015, Part B billing volume for phototherapy procedures increased 5% annually. However, phototherapy remains inaccessible in many locations due to unequal regional distribution of phototherapy clinics.⁶ Moreover, home phototherapy units are not yet widely utilized because of safety and efficacy concerns, lack of physician oversight, and difficulty obtaining insurance coverage.¹⁵ Acknowledgment and consideration of these geographical trends may persuasively allow policymakers, hospitals, and physicians to facilitate cost-effective phototherapy reimbursements that ensure continued access to quality and sustainable dermatologic care in the United States that tailor to regional needs.

In sum, this analysis reveals regional trends in Part B physician reimbursement for phototherapy procedures, with all US regions reporting a mean increase in phototherapy reimbursement after adjusting for utilization, albeit to varying degrees. Mean reimbursement for photochemotherapy by Goeckerman treatment or using petrolatum and UVB increased most among phototherapy procedures. Mean reimbursement for both actinotherapy and photochemotherapy using psoralen plus UVA decreased in all regions except the western United States.

Limitations include the restriction to Part B MPFS and the reliance on single-year (2020) physician utilization data to compute weighted changes in average reimbursement across a multiyear range, effectively restricting sweeping conclusions. Still, this study puts forth actionable insights for dermatologists and policymakers alike to appreciate and consider.