A Case of Nevus of Ota Associated with Agminated Blue Nevus.

Dermal melanocytosis is characterized by the presence of spindle-shaped melanocytes in the dermis. Common forms include Mongolian spots, nevus of Ota, nevus of Ito, and blue nevus. Nevus of Ota typically presents as bluish-brown patches involving the sclera and the cutaneous regions innervated by the ophthalmic and maxillary branches of the trigeminal nerve unilaterally. Blue nevus usually manifests as a solitary lesion. Agminated blue nevus is a rare variant that often presents as grouped, linear, or blaschkoid-distributed deep blue macules or papules. Only a few cases have reported the co-occurrence of nevus of Ota and agminated blue nevus. We herein report a case of extensive nevus of Ota combined with agminated blue nevus involving all three branches of the trigeminal nerve.