Erosive pustular dermatosis of the scalp: A case report

Abstract

Introduction: Erosive pustular dermatosis of the scalp (EPDS) is rare inflammatory dermatosis of unknown etiology, which mainly affects the scalp. The condition is characterized by sterile pustules, often with secondary bacterial colonization, erosions and crusts which lead to scarring alopecia. EPDS occurs in the elderly, more frequently in women. Patient report: A 55-year-old Caucasian female presented with a large atrophic erythematous plaque on the scalp, coated with pustules on the sides and covered with thick crusts and erosions. The patient reported a history of painless, moderately pruritic, enlarging lesions during three months prior to the admission to our department. She had no history of trauma, excessive sun exposure or some medical or cosmetic treatment (topical and systemic). Serological and immunologic tests (Hepatitis B and C, HIV; antinuclear antibodies, ANA) were negative. Fungal cultures were negative. Bacterial cultures grew Staphylococcus aureus. A scalp biopsy revealed polymorphous inflammatory infiltrate in the dermis of neutrophils, lymphocytes and plasma cells. Periodic acid Schiff (PAS) stain was negative. Direct immunofluorescence test was negative. Treatment with an oral antibiotic (rimfapicine) and potent topical corticosteroids led to marked and quick improvement but with remaining scarring alopecia. Conclusion: EPDS is a diagnosis of exclusion, based on clinical presentation, disease course and histopathological findings. It is necessary to exclude other differential diagnoses - autoimmune bullous disorders, malignancies, neutrophilic dermatoses, bacterial and fungal infections. A prompt diagnosis and treatment will reduce scarring.