Temporal Triangular Alopecia and a Review of 52 Past Cases

The document reports on a case of Temporal Triangular Alopecia (TTA) in a 15-year-old boy and reviews 52 past cases of TTA. TTA is a non-scarring, non-inflammatory form of alopecia that is confined to the frontotemporal region and is often detected in childhood. In the 53 cases reviewed, including the current case, 55.8% were detected between ages 2 and 9, 36.5% at birth, and only 3.8% in adulthood. There were three familial cases and associations with several congenital diseases such as phakomatosis pigmentovascularis, Down syndrome, and Dandy-Walker malformation. The histological examination of the boy's alopecia revealed miniaturized hair follicles with normal sebaceous and sweat glands, leading to a diagnosis of TTA. The findings suggest that TTA may be a hamartomatous mosaic disease, and future molecular and genetic studies are needed to understand its etiology.