Lyme borreliosis is a systemic infectious disease caused by Borrelia burgdorferi sensu lato transmitted by certain ticks of the genus Ixodes. Clinical spectrum of the disease includes mainly cutaneous (erythema migrans, lymphocytoma borreliensis, acrodermatitis chronica atrophicans), nervous, cardiovascular and locomotor systems. The diagnostics is based on direct and indirect proof of Borrelia infection. Indirect tests must correlate with the clinical manifestation, as to a high positivity of borrelial antibodies in health peo-ple, and negativity of borrelial antibodies during advanced infection. The antibiotic therapy is chosen according to the stage of the disease and the involved organ, as well. Therapy can fail as cystic forms of Bor¬relia burgdorferi or autoimmune reaction can develop. Some other bacteriae, námely Anaplasma phagocy¬tophilum, can také part in the cutaneous manifestation of Lyme borreliosis. The etiopathological relation-ship of Borreliae to other dermatoses (morphoea, lichen sclerosus et atrophicus), and to their possible ter-ratogenic effect on the fetus are still under discussion.

        Key words: lyme borreliosis - Borrelia burgdorferi sensu lato - Ixodes ricinus - erythema migrans - bor¬relial lymphocytoma - acrodermatitis chronica atrophicans - diagnostics - therapy