Lyme borreliosis--an unusual cause of vertigo.

A total of 2055 consecutive vertigo patients were examined in a prospective study in an area endemic for Lyme borreliosis for clinical signs of Lyme borreliosis or serum antibodies against Borrelia burgdorferi. Of these, 41 patients (2%) had positive levels of serum antibodies against B. burgdorferi. The incidence of seropositivity against B. burgdorferi among the vertigo patients did not differ from the incidence of the normal Finnish population. In addition to seropositivity the criteria used for Lyme borreliosis included previous erythema migrans, a positive polymerase chain reaction (PCR) or positive serum immunoblot. Eight patients were diagnosed as having Lyme borreliosis. This disease is a rare but possible cause of vertigo. Seropositivity alone is an insufficient finding for the diagnosis of Lyme borreliosis and should be supported by the clinical findings, the patient's history and other laboratory findings, such as immunoblotting or PCR. Although Lyme borreliosis seems to be a rare cause of vertigo, it must be kept in mind in the differential diagnosis of vertigo.