Perifolliculitis capitis abscedens et suffodiens: an uncommon case of cicatricial alopecia

Abstract

Perifolliculitis capitis abscedens et suffodiens (PCAS) is an uncommon inflammatory disorder of the scalp and a member of the follicular occlusion spectrum, characterized by chronic suppurative inflammation leading to scarring alopecia. Clinically, it manifests with pustules, inflammatory nodules, abscesses, interconnected sinus tracts, alopecic areas, and cicatricial plaques. Diagnosis relies on careful clinicopathological correlation. We report the case of an 18-year-old white male presenting with confluent inflammatory plaques, areas of reduced hair density, pustules, and comedones on scalp examination. Palpation of certain regions revealed fluctuant subcutaneous collections, creating a pseudobullous appearance, a finding consistent with dissecting cellulitis of the scalp. After histopathological analysis, PCAS was confirmed. Treatment was initiated with oral isotretinoin, 40 mg/day during the first month and 20 mg/day for the following seven months. After eight months of follow-up, the patient demonstrated a satisfactory therapeutic response, without recurrence while on isotretinoin maintenance dose, achieving dermatological remission and a significant improvement in quality of life. This case underscores the importance of early diagnosis of dissecting folliculitis, ensuring the correct treatment is implemented.