Lyme disease is a multisystem
disease caused by the spirochete Borrelia burgdorferi and is transmitted to humans primarily through Ixodid ticks. The clinical spectrum of the
disease is continuing to expand while in its wake the pathology and histopathologic manifestations are being uncovered. We review the pathology of
Lyme disease in man beginning with the tick bite. We present the pathologic changes of the rash, erythema migrans, as well as the neurologic, cardiac, and arthritic changes of the
disease. We can expand our understanding of the immunobiology of
Lyme disease by studying the interactions of B. burgdorferi in an experimental animal model.