Atraumatic spontaneous hemarthrosis associated with Lyme arthritis. A case report.

A 20-year-old male athlete had Lyme arthritis and an associated atraumatic spontaneous hemarthrosis of the knee. Lyme arthritis is a common and well-documented manifestation of Lyme disease, but an association with an atraumatic hemarthrosis to date has not been reported. Clinical diagnosis was confirmed by serologic testing. Treatment consisted of ceftriaxone, 1-g intravenous for 14 days.