Congenital Temporal Alopecia: Dermoscopic Features of Two Cases

Congenital triangular alopecia (CTA), also known as temporal triangular alopecia (TTA) or Brauer nevus, is a well circumscribed, nonscarring form of alopecia present over the temporal region. CTA was first reported by Sabouraud in 1905. It is characterized by triangular area of hair loss, more often occurs unilaterally. Most of the time it is not congenital, usually manifests after 2 years of age.. It may rarely appear in adulthood as well.The cause of CTA remains unknown. It usually occurs sporadically, but paradominant trait in familes has been reported.Histopathological examination shows normal number of hair follicles, most of it are vellus or indeterminate. CTA is more often misdiagnosed as alopecia areata and mistreated with steroids leading to development of adverse effects of steroids. CTA involves normal skin, thus topical or intralesional steroids are usually not effective. There is no specific treatment of this condition. This is a case report of 2 cases of CTA with clinical and trichoscopic features.