Compound Follicles in Folliculitis Decalvans Do Not Contain Vellus and Retained Telogen Follicles—A Pilot Histopathologic Series on Polytrichia

This study investigated the composition of compound follicular structures (CFS) in folliculitis decalvans (FD) by analyzing 10 scalp biopsy specimens from patients with early-stage FD. A total of 205 follicles were assessed, with 159 being part of CFS. The majority of these were terminal follicles, specifically 146 in the anagen phase and 10 in the telogen phase, with no vellus follicles present. The findings suggest that CFS in FD are predominantly composed of terminal anagen follicles, contributing to a better understanding of the disease's pathology.