Case 5

Erythema migrans is the most common skin manifestation of Lyme disease caused by Borrelia spp. There are some differences in the clinical presentation and aetiology between cases in Europe and the United States as the vectors and Borrelia spp. vary. The diagnosis is usually confirmed by serology, that is, enzyme immune-assay and Western blot, although there are other approaches such as PCR. Apart from erythema migrans, other manifestations include meningitis, heart block, and arthritis. There are a number of options for treatment, including tetracyclines and penicillins, and duration depends on the presence of complications. There is a limited if any role for prophylactic antibiotics to prevent acquisition after exposure to a tick. Much controversy surrounds chronic Lyme disease which may not be a real clinical entity and may mimic other conditions such as connective tissue diseases. There is no evidence that ongoing symptoms are due to persistent infection.