Pachyonychia Congenita-Associated Alopecia: A Microscopic Analysis Using Transverse Section Technique

Pachyonychia congenita (PC) is a rare genetic disorder characterized by nail abnormalities, and in some cases, alopecia, affecting about 10% of patients. This report provided the first microscopic analysis of PC-associated alopecia using the transverse section technique. The study identified specific histologic features such as reduced follicular density, follicular miniaturization, dyskeratosis of outer root sheath keratinocytes, and moderate follicular hyperkeratosis. While these features can appear in other types of nonscarring alopecia, their combination might be unique to PC-associated alopecia. The differential diagnoses considered included alopecia areata, androgenetic alopecia, and traction alopecia/trichotillomania.