Background: Folliculitis keloidalis (FK) is a chronic hair disorder commonly affecting males with afro-textured hair. It typically affects the nuchal area, but disease may also occur at extra-nuchal sites. Few studies have investigated the histopathological aspects of preclinical FK. In addition to the histopathology of preclinical FK, this article is the first to describe the dermoscopic features of preclinical FK at extra-nuchal sites.
Materials and methods: This study was conducted in a tertiary dermatological clinic. Twenty-eight patients with a clinical diagnosis of FK were prospectively enrolled from 2014 to 2016. Dermoscopy was used to identify features that were not evident with the naked eye (preclinical). These sites were subsequently biopsied. The clinical, dermoscopic, and histopathological features of these preclinical areas are described and correlated.
Results: Most patients suffered a chronic disease course (mean: 7.6 years) with 57.1% (n = 16) displaying extra-nuchal involvement. Dermoscopy-guided biopsy of preclinical lesions displayed perivascular dermatitis (82.1%), folliculocentric inflammation (46.3%), and fibrosis (64.3%). Novel dermoscopic findings were perifollicular scale, perifollicular erythema and pink-white areas. The perifollicular scale was associated with fibrosis on histopathology (P < 0.05).
Conclusions: This article lends further evidence for the existence of preclinical FK and describes its histological features. For the first time, it describes the dermoscopic features of preclinical FK. Dermoscopy may therefore be a useful tool to assess disease progression and treatment response.
© 2023 The Authors. International Journal of Dermatology published by Wiley Periodicals LLC on behalf of the International Society of Dermatology.