Folliculitis Decalvans and Lichen Planopilaris Phenotypic Spectrum-A Series of Four Patients.

Primary cicatricial alopecia of the scalp encompasses neutrophilic, lymphocytic, mixed varieties, of which folliculitis decalvans belongs to the neutrophilic group and lichen planopilaris comes under the lymphocytic group. This is a case series of four patients who presented clinically with folliculitis decalvans and histopathology with overlapping features. Four patients presented with a history of painful scalp pustular lesions and hair loss with no other significant history. A clinical diagnosis of folliculitis decalvans was made, and a biopsy for histopathological examination with vertical and transverse sections was studied. The histopathology of cases revealed features consistent with both folliculitis decalvans and lichen planopilaris. Folliculitis decalvans and lichen planopilaris phenotypic spectrum is an emerging entity with fewer cases reported in the literature.