Periungual hyperpigmentation mimicking Hutchinson's sign associated with minocycline administration.

An assessment of the occurrence rate of periungual hyperpigmentation with subungual melanoma (Hutchinson's sign) and periungual hyperpigmentation with other subungual lesions has not been published, although periungual hyperpigmentation with a pigmented streak or other pigmented lesion of the nail has been considered pathognomonic for subungual melanoma for a century. We report a case of minocycline hyperpigmentation presenting as a longitudinal pigmented streak of the nail associated with periungual hyperpigmentation. These pigmentary changes could be mistaken for Hutchinson's sign.