Melanotic macules of the tongue in a newborn

A newborn had 3 blue-black macules on the left side of the dorsal tongue. Clinical diagnosis was difficult. A biopsy specimen showed focal increase of melanin in the basal cells and subepithelial melanophages. The persistence of the lesions was unchanged at the age of 6 months, and the histologic features led to the diagnosis of oral physiologic melanosis.