[Tick-bite in penile skin : a case report].

A 42-year-old man who had no local or systemic symptoms presented with a yellowish tumor in the foreskin of his penis. He had travelled to Hokkaido to harvest insects, and recognized this tumor after returning home. Since it did not disappear after several days, he visited our hospital. The tumor was suspected to be due to an arthropod. En bloc resection including the arthropod was performed. Pathological findings demonstrated that the arthropod was Ixodes persulcatus. There were no symptoms after the surgery during the follow up. Ixodes persulcatus is a source of Lyme disease. Approximately ten patients develop Lyme disease per year, half of which are from Hokkaido in Japan. The case reported here was of a very rare tick-bite disease in the penis.