Cutis

Trachyonychia (“rough nails”) is best considered a reaction or morphologic pattern with a variety of clinical presentations and etiologies. It may involve only 1 or as many as 20 nails (20-nail dystrophy). It can be a manifestation of lichen planus, psoriasis, alopecia areata, immunoglobulin A deficiency, atopic dermatitis, and ichthyosis vulgaris. Nail matrix biopsy results and physical examination findings help in establishing the cause of this condition, though often trachyonychia is an isolated finding. When trachyonychia occurs in childhood as a manifestation of lichen planus, it tends to resolve with time. We review a case of trachyonychia, its association, its diagnostic evaluation, and treatment options.

Trachyonychia means "rough nails." This condition may involve only 1 or as many as 20 nails. It is best considered a reaction or morphologic pattern with a variety of clinical presentations and etiologies. Clinical presentations are rough nails with a sandpapered appearance and numerous small superficial pits that make the nails shiny1; onychorrhexis, onychoschizia, distal chipping, and yellow onychauxis of the great toenail; and closely arranged longitudinal ridges, distal notching, and layered splitting.2,3 Nail matrix biopsy results combined with clinical findings have linked trachyonychia with lichen planus generally,4 lichen planus in children,5 psoriasis,6 alopecia areata,7 IgA deficiency,8 atopic dermatitis,9 and ichthyosis vulgaris.10 The term 20-nail dystrophy of childhood11 refers to a trachyonychia variant likely caused by lichen planus. Some who consider the term a misnomer—in part because not all nails are necessarily involved—think that perhaps it should be abandoned.12 back to top

Case Report A 10-year-old girl presented with a 1-year history of worsening nail dystrophy. The patient had no history of psoriasis, atopic dermatitis, alopecia, or other skin disease, and family history was unremarkable. Except for dystrophy and hyperkeratosis identified on nails of both hands and both feet (Figure), physical examination findings were normal. Results of a fungal nail culture were negative, and the nail matrix biopsy specimen showed a bandlike lymphocytic infiltrate in the superficial dermis, with vacuolar alteration of the basal level. The diagnosis was trachyonychia secondary to lichen planus. Daily use of flurandrenolone tape and monthly intralesional injections of triamcinolone 2.5 mg/mL did not improve this patient's condition. After 4 months of injections in the distal nail folds, she was lost to follow-up.

back to top

Comment Often, the onset of trachyonychia is insidious. The condition usually develops on all nails simultaneously. Trachyonychia also can occur on individual nails over many months. Peak age of onset is 3 to 12 years. Trachyonychia occurs, however, in multigenerational families,13 in all age groups, in twins in the United States14 and Europe,15 in both sexes, and in all ethnic groups. This condition has been associated with ichthyosis vulgaris combined with alopecia universalis,16 ungual lichen planus and alopecia areata,17 koilonychia,18 primary biliary cirrhosis,19 and vitiligo.20 In chronic graft versus host (GVH) disease, trachyonychia can be an isolated finding21 or part of a constellation of cutaneous symptoms.22 It may be associated with dystrophy, atrophy, and, often, ulceration of the lunula.23 In the proper setting, the nail findings and clinical presentation of chronic GVH disease can resemble those of dyskeratosis congentia.24 A mother and her 7-year-old daughter with chronic GVH disease had balanced translocation 46, XX, t(6q13;10p13).25 A 15-year-old white boy with chronic GVH disease had recurrent episodes of immune thrombocytopenic purpura, autoimmune hemolytic anemia, and mild depression of immunoglobulin levels.26

Nail matrix biopsy results and physical examination findings help in establishing the cause of trachyonychia, though this condition often is an isolated finding.27 In the case of lichen planus,28 some patients also have flat polished purple papules on the body and white lacy or reticulated plaques in the mouth.29 Nail biopsy specimens can show hyperkeratosis, hypergranulosis, and acanthosis in the ventral portion of the proximal nail fold and in the nail matrix; a bandlike lymphocytic infiltrate in the superficial dermis; and vacuolar alterations in the basal layer. Nail abnormalities can develop in 1% to 10% of patients with lichen planus.30 In the case of psoriasis, psoriasiform plaques sometimes develop on other body areas, and nail biopsy specimens can show psoriasis evidence such as psoriasiform hyperplasia and neutrophils. In the case of atopic dermatitis, spongiosis31 (intercellular edema of the epidermis) also can occur in nail matrix biopsy specimens.32 In the case of alopecia areata, lymphocytes can be present in the nail matrix, patches of nonscarring alopecia can develop on the scalp, and nail pits can develop in a gridlike pattern (giving a pounded brass appearance) on the nail plates. Evaluation of trachyonychia should include a check for fungus—a fungal culture or periodic acid–Schiff staining of a nail clipping. Some authors have suggested that longitudinal nail biopsy may be a useful diagnostic tool in certain cases of acquired nail dystrophy.33

Hazelrigg et al11 stated that trachyonychia is self-limited and self-resolving in children. Specifically, trachyonychia tends to resolve with time when it occurs in childhood as a manifestation of lichen planus. Rarely, there is nail destruction in 20-nail dystrophy. If destruction occurs, the diagnosis is lichen planus—a form not restricted to the proximal nail fold but extended to the matrix. If the matrix is involved in lichen planus, a pterygium can develop—a manifestation rarely seen in 20-nail dystrophy.

Treatments for trachyonychia include intralesional injections of triamcinolone 2.5 to 3 mg/mL into the proximal nail folds.2,34 Injections are painful and thus difficult in children. Medications for systemic treatment include prednisolone,35 antimalarials,36 and etretinate.37 Seven-month therapy with topical psoralen and UVA light is reported effective.38 In treating psoriatic nail disease, topical 5-fluorouracil39 and cyclosporine40 are useful. Clear nail hardeners can be applied to nails to improve their appearance.

In a study of 15 children, intramuscularly injected triamcinolone acetonide 0.5 to 1 mg/kg per month was prescribed for children with typical nail lichen planus.41 Therapy duration was increased from 3 to 6 months, until the proximal half of the nail was normal. No treatment was prescribed for patients with 20-nail dystrophy or idiopathic atrophy of the nails. Treatment with systemic corticosteroids was effective in curing typical nail lichen planus. For 2 children, the disease recurred during follow-up. Recurrences were always responsive to therapy. Two children with 20-nail dystrophy improved without any therapy. Nail lesions caused by idiopathic atrophy of the nails remained unchanged during follow-up.

Trachyonychia and 20-nail dystrophy continue to present difficulties in classification, diagnosis, and treatment. With the advent of new immunomodulators, it is hoped that more effective treatments will be developed. Prompt diagnosis of these conditions aids in patient education and therapy. back to top

Trachyonychia (“rough nails”) is best considered a reaction or morphologic pattern with a variety of clinical presentations and etiologies. It may involve only 1 or as many as 20 nails (20-nail dystrophy). It can be a manifestation of lichen planus, psoriasis, alopecia areata, immunoglobulin A deficiency, atopic dermatitis, and ichthyosis vulgaris. Nail matrix biopsy results and physical examination findings help in establishing the cause of this condition, though often trachyonychia is an isolated finding. When trachyonychia occurs in childhood as a manifestation of lichen planus, it tends to resolve with time. We review a case of trachyonychia, its association, its diagnostic evaluation, and treatment options.

Trachyonychia means "rough nails." This condition may involve only 1 or as many as 20 nails. It is best considered a reaction or morphologic pattern with a variety of clinical presentations and etiologies. Clinical presentations are rough nails with a sandpapered appearance and numerous small superficial pits that make the nails shiny1; onychorrhexis, onychoschizia, distal chipping, and yellow onychauxis of the great toenail; and closely arranged longitudinal ridges, distal notching, and layered splitting.2,3 Nail matrix biopsy results combined with clinical findings have linked trachyonychia with lichen planus generally,4 lichen planus in children,5 psoriasis,6 alopecia areata,7 IgA deficiency,8 atopic dermatitis,9 and ichthyosis vulgaris.10 The term 20-nail dystrophy of childhood11 refers to a trachyonychia variant likely caused by lichen planus. Some who consider the term a misnomer—in part because not all nails are necessarily involved—think that perhaps it should be abandoned.12 back to top

Case Report A 10-year-old girl presented with a 1-year history of worsening nail dystrophy. The patient had no history of psoriasis, atopic dermatitis, alopecia, or other skin disease, and family history was unremarkable. Except for dystrophy and hyperkeratosis identified on nails of both hands and both feet (Figure), physical examination findings were normal. Results of a fungal nail culture were negative, and the nail matrix biopsy specimen showed a bandlike lymphocytic infiltrate in the superficial dermis, with vacuolar alteration of the basal level. The diagnosis was trachyonychia secondary to lichen planus. Daily use of flurandrenolone tape and monthly intralesional injections of triamcinolone 2.5 mg/mL did not improve this patient's condition. After 4 months of injections in the distal nail folds, she was lost to follow-up.

back to top

Comment Often, the onset of trachyonychia is insidious. The condition usually develops on all nails simultaneously. Trachyonychia also can occur on individual nails over many months. Peak age of onset is 3 to 12 years. Trachyonychia occurs, however, in multigenerational families,13 in all age groups, in twins in the United States14 and Europe,15 in both sexes, and in all ethnic groups. This condition has been associated with ichthyosis vulgaris combined with alopecia universalis,16 ungual lichen planus and alopecia areata,17 koilonychia,18 primary biliary cirrhosis,19 and vitiligo.20 In chronic graft versus host (GVH) disease, trachyonychia can be an isolated finding21 or part of a constellation of cutaneous symptoms.22 It may be associated with dystrophy, atrophy, and, often, ulceration of the lunula.23 In the proper setting, the nail findings and clinical presentation of chronic GVH disease can resemble those of dyskeratosis congentia.24 A mother and her 7-year-old daughter with chronic GVH disease had balanced translocation 46, XX, t(6q13;10p13).25 A 15-year-old white boy with chronic GVH disease had recurrent episodes of immune thrombocytopenic purpura, autoimmune hemolytic anemia, and mild depression of immunoglobulin levels.26

Nail matrix biopsy results and physical examination findings help in establishing the cause of trachyonychia, though this condition often is an isolated finding.27 In the case of lichen planus,28 some patients also have flat polished purple papules on the body and white lacy or reticulated plaques in the mouth.29 Nail biopsy specimens can show hyperkeratosis, hypergranulosis, and acanthosis in the ventral portion of the proximal nail fold and in the nail matrix; a bandlike lymphocytic infiltrate in the superficial dermis; and vacuolar alterations in the basal layer. Nail abnormalities can develop in 1% to 10% of patients with lichen planus.30 In the case of psoriasis, psoriasiform plaques sometimes develop on other body areas, and nail biopsy specimens can show psoriasis evidence such as psoriasiform hyperplasia and neutrophils. In the case of atopic dermatitis, spongiosis31 (intercellular edema of the epidermis) also can occur in nail matrix biopsy specimens.32 In the case of alopecia areata, lymphocytes can be present in the nail matrix, patches of nonscarring alopecia can develop on the scalp, and nail pits can develop in a gridlike pattern (giving a pounded brass appearance) on the nail plates. Evaluation of trachyonychia should include a check for fungus—a fungal culture or periodic acid–Schiff staining of a nail clipping. Some authors have suggested that longitudinal nail biopsy may be a useful diagnostic tool in certain cases of acquired nail dystrophy.33

Hazelrigg et al11 stated that trachyonychia is self-limited and self-resolving in children. Specifically, trachyonychia tends to resolve with time when it occurs in childhood as a manifestation of lichen planus. Rarely, there is nail destruction in 20-nail dystrophy. If destruction occurs, the diagnosis is lichen planus—a form not restricted to the proximal nail fold but extended to the matrix. If the matrix is involved in lichen planus, a pterygium can develop—a manifestation rarely seen in 20-nail dystrophy.

Treatments for trachyonychia include intralesional injections of triamcinolone 2.5 to 3 mg/mL into the proximal nail folds.2,34 Injections are painful and thus difficult in children. Medications for systemic treatment include prednisolone,35 antimalarials,36 and etretinate.37 Seven-month therapy with topical psoralen and UVA light is reported effective.38 In treating psoriatic nail disease, topical 5-fluorouracil39 and cyclosporine40 are useful. Clear nail hardeners can be applied to nails to improve their appearance.

In a study of 15 children, intramuscularly injected triamcinolone acetonide 0.5 to 1 mg/kg per month was prescribed for children with typical nail lichen planus.41 Therapy duration was increased from 3 to 6 months, until the proximal half of the nail was normal. No treatment was prescribed for patients with 20-nail dystrophy or idiopathic atrophy of the nails. Treatment with systemic corticosteroids was effective in curing typical nail lichen planus. For 2 children, the disease recurred during follow-up. Recurrences were always responsive to therapy. Two children with 20-nail dystrophy improved without any therapy. Nail lesions caused by idiopathic atrophy of the nails remained unchanged during follow-up.

Trachyonychia and 20-nail dystrophy continue to present difficulties in classification, diagnosis, and treatment. With the advent of new immunomodulators, it is hoped that more effective treatments will be developed. Prompt diagnosis of these conditions aids in patient education and therapy. back to top

Trachyonychia (“rough nails”) is best considered a reaction or morphologic pattern with a variety of clinical presentations and etiologies. It may involve only 1 or as many as 20 nails (20-nail dystrophy). It can be a manifestation of lichen planus, psoriasis, alopecia areata, immunoglobulin A deficiency, atopic dermatitis, and ichthyosis vulgaris. Nail matrix biopsy results and physical examination findings help in establishing the cause of this condition, though often trachyonychia is an isolated finding. When trachyonychia occurs in childhood as a manifestation of lichen planus, it tends to resolve with time. We review a case of trachyonychia, its association, its diagnostic evaluation, and treatment options.

Trachyonychia means "rough nails." This condition may involve only 1 or as many as 20 nails. It is best considered a reaction or morphologic pattern with a variety of clinical presentations and etiologies. Clinical presentations are rough nails with a sandpapered appearance and numerous small superficial pits that make the nails shiny1; onychorrhexis, onychoschizia, distal chipping, and yellow onychauxis of the great toenail; and closely arranged longitudinal ridges, distal notching, and layered splitting.2,3 Nail matrix biopsy results combined with clinical findings have linked trachyonychia with lichen planus generally,4 lichen planus in children,5 psoriasis,6 alopecia areata,7 IgA deficiency,8 atopic dermatitis,9 and ichthyosis vulgaris.10 The term 20-nail dystrophy of childhood11 refers to a trachyonychia variant likely caused by lichen planus. Some who consider the term a misnomer—in part because not all nails are necessarily involved—think that perhaps it should be abandoned.12 back to top

Case Report A 10-year-old girl presented with a 1-year history of worsening nail dystrophy. The patient had no history of psoriasis, atopic dermatitis, alopecia, or other skin disease, and family history was unremarkable. Except for dystrophy and hyperkeratosis identified on nails of both hands and both feet (Figure), physical examination findings were normal. Results of a fungal nail culture were negative, and the nail matrix biopsy specimen showed a bandlike lymphocytic infiltrate in the superficial dermis, with vacuolar alteration of the basal level. The diagnosis was trachyonychia secondary to lichen planus. Daily use of flurandrenolone tape and monthly intralesional injections of triamcinolone 2.5 mg/mL did not improve this patient's condition. After 4 months of injections in the distal nail folds, she was lost to follow-up.

back to top

Comment Often, the onset of trachyonychia is insidious. The condition usually develops on all nails simultaneously. Trachyonychia also can occur on individual nails over many months. Peak age of onset is 3 to 12 years. Trachyonychia occurs, however, in multigenerational families,13 in all age groups, in twins in the United States14 and Europe,15 in both sexes, and in all ethnic groups. This condition has been associated with ichthyosis vulgaris combined with alopecia universalis,16 ungual lichen planus and alopecia areata,17 koilonychia,18 primary biliary cirrhosis,19 and vitiligo.20 In chronic graft versus host (GVH) disease, trachyonychia can be an isolated finding21 or part of a constellation of cutaneous symptoms.22 It may be associated with dystrophy, atrophy, and, often, ulceration of the lunula.23 In the proper setting, the nail findings and clinical presentation of chronic GVH disease can resemble those of dyskeratosis congentia.24 A mother and her 7-year-old daughter with chronic GVH disease had balanced translocation 46, XX, t(6q13;10p13).25 A 15-year-old white boy with chronic GVH disease had recurrent episodes of immune thrombocytopenic purpura, autoimmune hemolytic anemia, and mild depression of immunoglobulin levels.26

Nail matrix biopsy results and physical examination findings help in establishing the cause of trachyonychia, though this condition often is an isolated finding.27 In the case of lichen planus,28 some patients also have flat polished purple papules on the body and white lacy or reticulated plaques in the mouth.29 Nail biopsy specimens can show hyperkeratosis, hypergranulosis, and acanthosis in the ventral portion of the proximal nail fold and in the nail matrix; a bandlike lymphocytic infiltrate in the superficial dermis; and vacuolar alterations in the basal layer. Nail abnormalities can develop in 1% to 10% of patients with lichen planus.30 In the case of psoriasis, psoriasiform plaques sometimes develop on other body areas, and nail biopsy specimens can show psoriasis evidence such as psoriasiform hyperplasia and neutrophils. In the case of atopic dermatitis, spongiosis31 (intercellular edema of the epidermis) also can occur in nail matrix biopsy specimens.32 In the case of alopecia areata, lymphocytes can be present in the nail matrix, patches of nonscarring alopecia can develop on the scalp, and nail pits can develop in a gridlike pattern (giving a pounded brass appearance) on the nail plates. Evaluation of trachyonychia should include a check for fungus—a fungal culture or periodic acid–Schiff staining of a nail clipping. Some authors have suggested that longitudinal nail biopsy may be a useful diagnostic tool in certain cases of acquired nail dystrophy.33

Hazelrigg et al11 stated that trachyonychia is self-limited and self-resolving in children. Specifically, trachyonychia tends to resolve with time when it occurs in childhood as a manifestation of lichen planus. Rarely, there is nail destruction in 20-nail dystrophy. If destruction occurs, the diagnosis is lichen planus—a form not restricted to the proximal nail fold but extended to the matrix. If the matrix is involved in lichen planus, a pterygium can develop—a manifestation rarely seen in 20-nail dystrophy.

Treatments for trachyonychia include intralesional injections of triamcinolone 2.5 to 3 mg/mL into the proximal nail folds.2,34 Injections are painful and thus difficult in children. Medications for systemic treatment include prednisolone,35 antimalarials,36 and etretinate.37 Seven-month therapy with topical psoralen and UVA light is reported effective.38 In treating psoriatic nail disease, topical 5-fluorouracil39 and cyclosporine40 are useful. Clear nail hardeners can be applied to nails to improve their appearance.

In a study of 15 children, intramuscularly injected triamcinolone acetonide 0.5 to 1 mg/kg per month was prescribed for children with typical nail lichen planus.41 Therapy duration was increased from 3 to 6 months, until the proximal half of the nail was normal. No treatment was prescribed for patients with 20-nail dystrophy or idiopathic atrophy of the nails. Treatment with systemic corticosteroids was effective in curing typical nail lichen planus. For 2 children, the disease recurred during follow-up. Recurrences were always responsive to therapy. Two children with 20-nail dystrophy improved without any therapy. Nail lesions caused by idiopathic atrophy of the nails remained unchanged during follow-up.

Trachyonychia and 20-nail dystrophy continue to present difficulties in classification, diagnosis, and treatment. With the advent of new immunomodulators, it is hoped that more effective treatments will be developed. Prompt diagnosis of these conditions aids in patient education and therapy. back to top

Orf, also known as contagious ecthyma, scabby mouth, soremouth, contagious pustular dermatitis, and ovine pustular dermatitis, is caused by a member of the genus Parapoxvirus in the family Poxviridae.^1,2 The virus typically infects sheep or goats and produces papulovesicular lesions on non–wool-bearing areas (eg, gums, lips, nose, groin).^3,4 The infection can be transmitted to humans either by direct contact with an infected animal or by indirect contact with contaminated fomites.^4,5 After an incubation period of 3 to 7 days, an erythematous maculopapular lesion develops.^1,4 Orf lesions are benign and progress to complete resolution in 6 weeks.⁴ 

Case Report

A 51-year-old woman presented to her primary care physician for evaluation of a lesion on the metacarpal-phalangeal joint of the left second digit. A raised annular lesion was identified, and the patient was started on dicloxacillin therapy. On reexamination 4 days later, an enlarging 2-cm nodule with signs of central necrosis was found. The lesion was incised, and a bacterial culture of purulent exudate was obtained. Gram stain and initial culture results were negative. The patient also complained of diarrhea, which was attributed to use of dicloxacillin; this antibiotic was replaced with clarithromycin. The patient was reevaluated the next day for signs of cellulitis and ascending lymphangitis. She denied constitutional symptoms or fever and chills. The lymphangitis was present on the dorsum of the left hand to the level of the wrist. Ceftriaxone was injected intramuscularly. Three days later, an enlarging lesion with serous discharge was identified. The patient was referred for further dermatologic evaluation.

On examining the patient, we found a 2.5-cm boggy fluctuant nodule over the metacarpal-phalangeal joint of the left second digit (Figure). The patient complained of pain, and the hand showed signs of lymphangitic spread. When her history was taken, the patient indicated that she worked at a deer station. Her job involved handling deer carcasses, and her bare hands had been exposed to blood from slaughtered deer. She denied having any contact with sheep, goats, cattle, and farm structures containing those animals. Results of bacterial cultures were negative, and a differential diagnosis of deep fungal infection, atypical mycobacterial infection, or contagious ecthyma was entertained. Two 3-mm punch biopsies were performed. Stains for acid-fast bacilli and fungi were negative. Results of microscopic examination showed vacuolation of cells in the upper third of the malpighian stratum, eosinophilic inclusion bodies, and massive dermal infiltrate.

PLEASE REFER TO THE PDF TO VIEW THE FIGURE

Because of the patient's clinical presentation, microscopic findings, and negative culture results, orf was diagnosed. Oral antibiotic therapy was discontinued, and daily cleansing and use of bacitracin ointment were started. The lesion resolved completely over the ensuing 3 to 4 weeks. 

Comment

The diagnosis of orf is suggested by a characteristic skin lesion and a history of exposure. The typical lesion begins as a solitary papule on a finger, a hand,³ or the face.⁶ Orf lesions classically progress through a series of 6 clinical and histopathologic stages, each lasting approximately 1 week. In the initial maculopapular stage, an erythematous macule or papule erupts. In the target stage, the lesion becomes a papule with a red center, a white middle ring, and a red halo. In the acute stage, the lesion becomes a weeping nodule. In the regenerative stage, the lesion dries, a thin yellow crust develops, and small black dots form on the surface. In the papillomatous stage, tiny papillomas form on the surface. In the final, regressive stage, a dry crust forms.^1,3,4,6 Uncomplicated lesions rarely leave a residual scar.⁴

The histopathology of an orf lesion evolves with the clinical stages and helps to secure the diagnosis. The maculopapular and target stages are characterized by vacuolated epidermal cells. In the maculopapular stage, cells have intracytoplasmic inclusions; in the target stage, they have both intracytoplasmic and intranuclear inclusions. The acute stage is marked by patchy areas of lost epidermis, reticular degeneration of the epidermis, and a dermal infiltrate composed primarily of lymphocytes. The regenerative stage involves epidermal regeneration and extrusion of pyknotic hair-follicle cells that form the small black dots on the surface of the lesion. In the papillomatous and regressive stages, fingerlike downward projections of epidermis are evident.^1,4,6

The diagnosis of orf is further supported by a history of exposure to infected animals. The most compelling history involves exposure to sheep or goats, but the orf virus has infected other animals, including musk oxen⁷ and camels.⁸ Experimental inoculation has produced contagious ecthyma lesions in mule deer, white-tailed deer, pronghorn, and wapiti.⁹ That wild deer could contract orf and that the infection could be transmitted to humans through direct contact seem reasonable speculations. Our patient's clinical picture suggests that this mechanism may have been involved in her contracting the disease.

Electron microscopic views of characteristic viral particles in the cytoplasm of keratinocytes provide the definitive diagnosis of orf.^1,10 Other diagnostic studies are tests of viral culture, complement fixation, and immunofluorescence.^1,4,6 These tests are used mainly for epidemiology rather than clinical diagnosis.⁶

Complications of orf are generally rare but may include fever, chills, rigor, drenching sweat, malaise, lymphadenopathy, and lymphangitis.^1,6,10 Secondary bacterial infection is the most common complication.¹ Cases of erythema multiforme also have developed in the presence of orf.¹¹

As a benign self-limited disease, orf requires no specific treatment. Antibiotics should be administered in cases of secondary bacterial infection but are otherwise unnecessary.^1,2,6 Regression of the lesion may be accelerated by application of idoxuridine.¹⁰ Surgical excision also can bring about rapid resolution but is generally contraindicated because the lesion spontaneously regresses without leaving a scar.² Corticosteroids and other immunosuppressive drugs should be avoided because they can exacerbate the lesion in its papillomatous stage.^6,12 Use of topical cidofovir has been beneficial in treating patients who are immunocompromised.¹³

Although orf is a benign disease with a striking presentation that is easy to spot, early diagnosis can prevent unnecessary diagnostic workup and treatment.¹ Orf should be considered in patients presenting with the characteristic skin lesion and a history of exposure to sheep or goats. As with our case, however, when a patient presents with a characteristic lesion and a history of exposure to other animals, orf should be kept in the differential diagnosis. 

Orf, also known as contagious ecthyma, scabby mouth, soremouth, contagious pustular dermatitis, and ovine pustular dermatitis, is caused by a member of the genus Parapoxvirus in the family Poxviridae.^1,2 The virus typically infects sheep or goats and produces papulovesicular lesions on non–wool-bearing areas (eg, gums, lips, nose, groin).^3,4 The infection can be transmitted to humans either by direct contact with an infected animal or by indirect contact with contaminated fomites.^4,5 After an incubation period of 3 to 7 days, an erythematous maculopapular lesion develops.^1,4 Orf lesions are benign and progress to complete resolution in 6 weeks.⁴ 

Case Report

A 51-year-old woman presented to her primary care physician for evaluation of a lesion on the metacarpal-phalangeal joint of the left second digit. A raised annular lesion was identified, and the patient was started on dicloxacillin therapy. On reexamination 4 days later, an enlarging 2-cm nodule with signs of central necrosis was found. The lesion was incised, and a bacterial culture of purulent exudate was obtained. Gram stain and initial culture results were negative. The patient also complained of diarrhea, which was attributed to use of dicloxacillin; this antibiotic was replaced with clarithromycin. The patient was reevaluated the next day for signs of cellulitis and ascending lymphangitis. She denied constitutional symptoms or fever and chills. The lymphangitis was present on the dorsum of the left hand to the level of the wrist. Ceftriaxone was injected intramuscularly. Three days later, an enlarging lesion with serous discharge was identified. The patient was referred for further dermatologic evaluation.

On examining the patient, we found a 2.5-cm boggy fluctuant nodule over the metacarpal-phalangeal joint of the left second digit (Figure). The patient complained of pain, and the hand showed signs of lymphangitic spread. When her history was taken, the patient indicated that she worked at a deer station. Her job involved handling deer carcasses, and her bare hands had been exposed to blood from slaughtered deer. She denied having any contact with sheep, goats, cattle, and farm structures containing those animals. Results of bacterial cultures were negative, and a differential diagnosis of deep fungal infection, atypical mycobacterial infection, or contagious ecthyma was entertained. Two 3-mm punch biopsies were performed. Stains for acid-fast bacilli and fungi were negative. Results of microscopic examination showed vacuolation of cells in the upper third of the malpighian stratum, eosinophilic inclusion bodies, and massive dermal infiltrate.

PLEASE REFER TO THE PDF TO VIEW THE FIGURE

Because of the patient's clinical presentation, microscopic findings, and negative culture results, orf was diagnosed. Oral antibiotic therapy was discontinued, and daily cleansing and use of bacitracin ointment were started. The lesion resolved completely over the ensuing 3 to 4 weeks. 

Comment

The diagnosis of orf is suggested by a characteristic skin lesion and a history of exposure. The typical lesion begins as a solitary papule on a finger, a hand,³ or the face.⁶ Orf lesions classically progress through a series of 6 clinical and histopathologic stages, each lasting approximately 1 week. In the initial maculopapular stage, an erythematous macule or papule erupts. In the target stage, the lesion becomes a papule with a red center, a white middle ring, and a red halo. In the acute stage, the lesion becomes a weeping nodule. In the regenerative stage, the lesion dries, a thin yellow crust develops, and small black dots form on the surface. In the papillomatous stage, tiny papillomas form on the surface. In the final, regressive stage, a dry crust forms.^1,3,4,6 Uncomplicated lesions rarely leave a residual scar.⁴

The histopathology of an orf lesion evolves with the clinical stages and helps to secure the diagnosis. The maculopapular and target stages are characterized by vacuolated epidermal cells. In the maculopapular stage, cells have intracytoplasmic inclusions; in the target stage, they have both intracytoplasmic and intranuclear inclusions. The acute stage is marked by patchy areas of lost epidermis, reticular degeneration of the epidermis, and a dermal infiltrate composed primarily of lymphocytes. The regenerative stage involves epidermal regeneration and extrusion of pyknotic hair-follicle cells that form the small black dots on the surface of the lesion. In the papillomatous and regressive stages, fingerlike downward projections of epidermis are evident.^1,4,6

The diagnosis of orf is further supported by a history of exposure to infected animals. The most compelling history involves exposure to sheep or goats, but the orf virus has infected other animals, including musk oxen⁷ and camels.⁸ Experimental inoculation has produced contagious ecthyma lesions in mule deer, white-tailed deer, pronghorn, and wapiti.⁹ That wild deer could contract orf and that the infection could be transmitted to humans through direct contact seem reasonable speculations. Our patient's clinical picture suggests that this mechanism may have been involved in her contracting the disease.

Electron microscopic views of characteristic viral particles in the cytoplasm of keratinocytes provide the definitive diagnosis of orf.^1,10 Other diagnostic studies are tests of viral culture, complement fixation, and immunofluorescence.^1,4,6 These tests are used mainly for epidemiology rather than clinical diagnosis.⁶

Complications of orf are generally rare but may include fever, chills, rigor, drenching sweat, malaise, lymphadenopathy, and lymphangitis.^1,6,10 Secondary bacterial infection is the most common complication.¹ Cases of erythema multiforme also have developed in the presence of orf.¹¹

As a benign self-limited disease, orf requires no specific treatment. Antibiotics should be administered in cases of secondary bacterial infection but are otherwise unnecessary.^1,2,6 Regression of the lesion may be accelerated by application of idoxuridine.¹⁰ Surgical excision also can bring about rapid resolution but is generally contraindicated because the lesion spontaneously regresses without leaving a scar.² Corticosteroids and other immunosuppressive drugs should be avoided because they can exacerbate the lesion in its papillomatous stage.^6,12 Use of topical cidofovir has been beneficial in treating patients who are immunocompromised.¹³

Although orf is a benign disease with a striking presentation that is easy to spot, early diagnosis can prevent unnecessary diagnostic workup and treatment.¹ Orf should be considered in patients presenting with the characteristic skin lesion and a history of exposure to sheep or goats. As with our case, however, when a patient presents with a characteristic lesion and a history of exposure to other animals, orf should be kept in the differential diagnosis. 

Orf, also known as contagious ecthyma, scabby mouth, soremouth, contagious pustular dermatitis, and ovine pustular dermatitis, is caused by a member of the genus Parapoxvirus in the family Poxviridae.^1,2 The virus typically infects sheep or goats and produces papulovesicular lesions on non–wool-bearing areas (eg, gums, lips, nose, groin).^3,4 The infection can be transmitted to humans either by direct contact with an infected animal or by indirect contact with contaminated fomites.^4,5 After an incubation period of 3 to 7 days, an erythematous maculopapular lesion develops.^1,4 Orf lesions are benign and progress to complete resolution in 6 weeks.⁴ 

Case Report

A 51-year-old woman presented to her primary care physician for evaluation of a lesion on the metacarpal-phalangeal joint of the left second digit. A raised annular lesion was identified, and the patient was started on dicloxacillin therapy. On reexamination 4 days later, an enlarging 2-cm nodule with signs of central necrosis was found. The lesion was incised, and a bacterial culture of purulent exudate was obtained. Gram stain and initial culture results were negative. The patient also complained of diarrhea, which was attributed to use of dicloxacillin; this antibiotic was replaced with clarithromycin. The patient was reevaluated the next day for signs of cellulitis and ascending lymphangitis. She denied constitutional symptoms or fever and chills. The lymphangitis was present on the dorsum of the left hand to the level of the wrist. Ceftriaxone was injected intramuscularly. Three days later, an enlarging lesion with serous discharge was identified. The patient was referred for further dermatologic evaluation.

On examining the patient, we found a 2.5-cm boggy fluctuant nodule over the metacarpal-phalangeal joint of the left second digit (Figure). The patient complained of pain, and the hand showed signs of lymphangitic spread. When her history was taken, the patient indicated that she worked at a deer station. Her job involved handling deer carcasses, and her bare hands had been exposed to blood from slaughtered deer. She denied having any contact with sheep, goats, cattle, and farm structures containing those animals. Results of bacterial cultures were negative, and a differential diagnosis of deep fungal infection, atypical mycobacterial infection, or contagious ecthyma was entertained. Two 3-mm punch biopsies were performed. Stains for acid-fast bacilli and fungi were negative. Results of microscopic examination showed vacuolation of cells in the upper third of the malpighian stratum, eosinophilic inclusion bodies, and massive dermal infiltrate.

PLEASE REFER TO THE PDF TO VIEW THE FIGURE

Because of the patient's clinical presentation, microscopic findings, and negative culture results, orf was diagnosed. Oral antibiotic therapy was discontinued, and daily cleansing and use of bacitracin ointment were started. The lesion resolved completely over the ensuing 3 to 4 weeks. 

Comment

The diagnosis of orf is suggested by a characteristic skin lesion and a history of exposure. The typical lesion begins as a solitary papule on a finger, a hand,³ or the face.⁶ Orf lesions classically progress through a series of 6 clinical and histopathologic stages, each lasting approximately 1 week. In the initial maculopapular stage, an erythematous macule or papule erupts. In the target stage, the lesion becomes a papule with a red center, a white middle ring, and a red halo. In the acute stage, the lesion becomes a weeping nodule. In the regenerative stage, the lesion dries, a thin yellow crust develops, and small black dots form on the surface. In the papillomatous stage, tiny papillomas form on the surface. In the final, regressive stage, a dry crust forms.^1,3,4,6 Uncomplicated lesions rarely leave a residual scar.⁴

The histopathology of an orf lesion evolves with the clinical stages and helps to secure the diagnosis. The maculopapular and target stages are characterized by vacuolated epidermal cells. In the maculopapular stage, cells have intracytoplasmic inclusions; in the target stage, they have both intracytoplasmic and intranuclear inclusions. The acute stage is marked by patchy areas of lost epidermis, reticular degeneration of the epidermis, and a dermal infiltrate composed primarily of lymphocytes. The regenerative stage involves epidermal regeneration and extrusion of pyknotic hair-follicle cells that form the small black dots on the surface of the lesion. In the papillomatous and regressive stages, fingerlike downward projections of epidermis are evident.^1,4,6

The diagnosis of orf is further supported by a history of exposure to infected animals. The most compelling history involves exposure to sheep or goats, but the orf virus has infected other animals, including musk oxen⁷ and camels.⁸ Experimental inoculation has produced contagious ecthyma lesions in mule deer, white-tailed deer, pronghorn, and wapiti.⁹ That wild deer could contract orf and that the infection could be transmitted to humans through direct contact seem reasonable speculations. Our patient's clinical picture suggests that this mechanism may have been involved in her contracting the disease.

Electron microscopic views of characteristic viral particles in the cytoplasm of keratinocytes provide the definitive diagnosis of orf.^1,10 Other diagnostic studies are tests of viral culture, complement fixation, and immunofluorescence.^1,4,6 These tests are used mainly for epidemiology rather than clinical diagnosis.⁶

Complications of orf are generally rare but may include fever, chills, rigor, drenching sweat, malaise, lymphadenopathy, and lymphangitis.^1,6,10 Secondary bacterial infection is the most common complication.¹ Cases of erythema multiforme also have developed in the presence of orf.¹¹

As a benign self-limited disease, orf requires no specific treatment. Antibiotics should be administered in cases of secondary bacterial infection but are otherwise unnecessary.^1,2,6 Regression of the lesion may be accelerated by application of idoxuridine.¹⁰ Surgical excision also can bring about rapid resolution but is generally contraindicated because the lesion spontaneously regresses without leaving a scar.² Corticosteroids and other immunosuppressive drugs should be avoided because they can exacerbate the lesion in its papillomatous stage.^6,12 Use of topical cidofovir has been beneficial in treating patients who are immunocompromised.¹³

Although orf is a benign disease with a striking presentation that is easy to spot, early diagnosis can prevent unnecessary diagnostic workup and treatment.¹ Orf should be considered in patients presenting with the characteristic skin lesion and a history of exposure to sheep or goats. As with our case, however, when a patient presents with a characteristic lesion and a history of exposure to other animals, orf should be kept in the differential diagnosis.