Alopecia areata incognita in men masquerading as androgenetic alopecia: a case series of 29 patients in a single centre experience.

Abstract

Background: Alopecia areata incognita (AAI) represents a variant of alopecia areata with an absence of well-defined alopecic patches but diffuse involvement of the scalp and even if usually affected females, it may also appear in male. Little is known about AAI in men. The aim of this study was to characterize the history, clinical, trichoscopic, and histopathologic features of AAI in male patients.

Methods: All histopathologically proven male patients with AAI between April 2011 and December 2023, were included in the study. The history, clinical, trichoscopic and histopathologic features of the male patients were evaluated.

Results: Twenty-nine patients with AAI were included in the study, the mean age was 23.1. All patients had an underlying androgenetic alopecia (AGA) - Hamilton Scale: 17 (58.62%) grade IV, 9 (31.03%) grade V and 3 (10.34%) grade VI. The most common trichoscopic features included short regrowing hair (96.6%), yellow dots (89.7%) and pigtail hair (41.3%) especially seen in the occipital, parietal and frontal regions. A positive pull test with telogen roots was observed in 24.1% of the patients. Histopathological characteristics of AAI in male patients were indistinguishable from previously described features in female patients. All patients were treated with an ultra-potent topical corticosteroid under occlusion and topical 5% minoxidil twice/day or oral minoxidil, remission was established between 4-8 months after treatment initiation.

Conclusions: A thorough trichoscopic examination in cases of diffuse hair loss in male patients with AGA refractory to conventional therapy is warranted and trichoscopy-guided biopsy is necessary to confirm the diagnosis.