Congenital triangular alopecia: case report

Camila A. Alves, Department of Dermatology, Hospital Central do Exército, Rio de Janeiro, RJ, Brazil Leninha V. do Nascimento, Department of Dermatology, Hospital Central do Exército, Rio de Janeiro, RJ, Brazil Hugo M. Faver, Department of Dermatology, Hospital Central do Exército, Rio de Janeiro, RJ, Brazil Angela C. Nascimento, Department of Dermatology, Hospital Central do Exército, Rio de Janeiro, RJ, Brazil Vivian M. S. Correa-da-Silva, Department of Dermatology, Hospital Central do Exército, Rio de Janeiro, RJ, Brazil Andreza L. Rodrigues-Moreira-da Silva, Department of Dermatology, Hospital Central do Exército, Rio de Janeiro, RJ, Brazil

The authors present a case of congenital triangular alopecia (CTA), also known as temporal triangular alopecia, and debate its clinical presentation and diagnostic considerations. The patient, a 15-year-old male without comorbidities, exhibited left temporal alopecia since birth, seeking medical attention due to esthetic concerns. Dermatological examination revealed a well-defined area of alopecia, and trichoscopy exhibited vellus hairs of varying lengths, surrounded by terminal follicles and white hairs which are characteristic findings of the disease. The discussion explores the possible congenital nature of CTA, its clinical and trichoscopic features, histopathological characteristics, and the necessity for accurate differential diagnosis.

Keywords: Congenital alopecia. Non-cicatricial alopecia. Congenital triangular alopecia. Alopecia areata.