Twenty-Nail Transverse Melanonychia Induced by Hydroxyurea: Case Report and Review of the Literature.

<p>Twenty-nail transverse melanonychia from hydroxyurea is a rare phenomenon, only reported four times previously. Here we describe a 51-year-old female who presented with 20-nail transverse melanonychia 3 months after initiating hydroxyurea therapy. Transverse melanonychia is a benign process but can cause patients significant distress, and thus is an entity with which dermatologists should recognize. We then review the cutaneous manifestations, differential diagnosis, and clinical considerations when evaluating patients with transverse melanonychia from hydroxyurea or other causes.</p> <p><em>J Drugs Dermatol. 2017;16(8):814-815.</em></p>.