A 27-Year-Old Man with a Lesion on One Hand

A 27-year-old man presents complaining of a single skin lesion on his hand. He reports that it first appeared as a smooth nodule that ulcerated and spread in a lymphangitic fashion. He grew worried when he started to have a fever. The only unusual activity he’d done in the last few weeks was clean out one of his large saltwater aquariums to prepare for purchasing new fish.

View the photo and consider what your diagnosis and next steps would be. Resolution of the case is described on the next page.