Transient Treatment Response of Platelet-rich Plasma Injection for Temporal Triangular Alopecia: A Case Report with Dermoscopic Examination Follow-up.

Temporal triangular alopecia (TTA) is congenital anomalies that usually develops in childhood, with rarely acquired cases in adults. TTA shares common clinical, dermoscopic, and histologic features of characterized vellus hair formation change, similar to androgenetic alopecia (AGA). Whereas, platelet-rich plasma (PRP) with multiple growth factors can provide treatment efficacy in AGA. Due to limited treatment for TTA, such as topical minoxidil, complete surgical excision, and hair transplantation, the multiple growth factors in PRP is thus postulated to be also effective for TTA treatment, just as in AGA. We present a case of TTA with unsatisfactory treatment outcome of only increased number and thickness of vellus hair by dermoscopic examination follow-up after the 5-session PRP injection and only transient response for 6 months. Unlike, AGA, the PRP injection might not consequently be a suitable treatment option for TTA. Nonetheless, further studies should be performed to investigate the potential treatment modality for TTA.