[Cutaneous manifestations of Lyme disease : Pitfalls in the serological diagnostic workup]

Serology, the detection of B. burgdorferi-specific IgM and IgG serum antibodies, is the most common laboratory test to diagnose cutaneous manifestations of Lyme disease. In a two-tiered approach, an ELISA is used as a screening test. A positive or equivocal ELISA result needs confirmation by a specific immunoblot. The sensitivity of this approach reaches 80-95%. The diagnosis of erythema migrans is based on its typical clinical appearance. Serology is only indicated in atypical cases. In contrast, serology is mandatory in the diagnostic workup of borrelial lymphocytoma and acrodermatitis chronica atrophicans. A positive serology can persist for many years, even after adequate antibiotic treatment. A positive serology is no indication for antibiotic treatment if typical symptoms of Lyme disease are absent.