[Differential diagnosis of idiopathic facial paralysis: Bannwarth meningopolyradiculitis].

Lymphocytic meningopolyradiculitis (Bannwarths' syndrome) is a tick-borne Borrelia infection of man. About 60 per cent of such patients exhibit a peripheral facial paresis whose characteristics are clinically not distinguishable from Bell's paresis. Of major importance for the diagnosis, besides the radicular pain that nearly always prevails, are particularly further motoric deficits, a previous erythema migrans and remembered thick bites. A tentative diagnosis can be verified by liquor examination which reveals a characteristic pattern of protein distribution and lymphocytic pleocytosis. Penicillin in high doses is the therapy of choice.