Mucha-Habermann disease in a 72 year old man with recurrent skin papules and leg ulcers

Backround: Mucha-Habermann disease, otherwise known as Pityriasis lichenoides et varioliformis acuta (PLEVA) is a rare cutaneous inflammatory disorder that usually presents as an acute eruption of inflammatory papules and papulovesicles with rapid progression to hemorrhagic or necrotic crusts. Cutaneous lesions may be asymptomatic, pruritic, or associated with a burning sensation. PLEVA commonly refers to a spectrum of inflammatory disorders.Case report: A diabetic 72 year old man was admitted for pruritic erythematous eruption with scaly maculopapules and ulceronecrotic - crusted lesions measuring 5–25 mm, localized on his trunk and lower extremities. The patient reported a relapsing and remitting course of the rash for one year. Laboratory investigation showed leukocytosis and CRP elevation. Viral serology liver and renal studies, C3, C4, serum protein electrophoresis, immunoglobulins, antinuclear antibodies and bacterial cultures were normal. Punch biopsy was performed. Histopathology showed parakeratosis, mild epidermal acanthosis, exocytosis of erythrocytes and lymphocytes, vacuolizasion of the basal layer, presence of necrotic keratinocytes and extensive lymphocytic inflammatory infiltrates. Diagnosis of PLEVA was established from the association of clinical and histological data. The patient received therapy with topical steroids, doxycycline, and methylprednisolone. Periodical follow up and annual consultation for a full skin examination was advised.Conclusion: PLEVA is a rare entity that presents difficulties in both diagnosis and treatment. Patients with refractory disease may require UVB phototherapy or methotrexate administration as an adjunct to first line treatment. Despite its benign and self-limiting course, it may be associated with cutaneous lymphoma, so annual full skin examination is indicated.