Erythema Chronicum Migrans in Lyme Disease

A 34-year-old man experienced fever and arthralgia several days after appearance of the rash shown here (A). He did not recall being bitten by a tick, as is often the case with persons who contract Lyme disease. The characteristic rash of Lyme disease-an annular red eruption with a central clear area-is observed in fewer than 50% of cases. Variations include an ecchymosis-like rash, such as the one seen here; vesicles; and diffuse erythema.

Macular eruption resulting from Lyme disease is seen in the axilla of a 30-year-old man (B) and on the back of a 71-year-old woman (C).