Tick-borne borreliosis and facial palsy.

During a one-year period, 82 consecutive patients seeking medical attention for facial palsy primarily of unknown etiology were examined for underlying Ixodes ricinus-borne borreliosis. Evidence of the infection was found in 16 (20%) of the patients, most of whom had cerebrospinal fluid findings indicating meningeal involvement. Among 9 children included in the study, borreliosis was found in 6 cases. Bilateral facial palsy occurred in 3 of the borrelia-infected patients, as compared with none of the patients without borreliosis. It is suggested that, in areas where the tick vector is present, borreliosis should be regularly sought in patients with facial palsy of otherwise unknown etiology. As regards the serological diagnosis, it is emphasized that normal borrelia antibody titres in serum and cerebrospinal fluid at the time of the first consultation do not exclude the infection. A careful serological follow-up of patients with facial palsy is therefore recommended in order not to miss an underlying borreliosis which, if allowed to go untreated, implies a risk of other organ involvement and a protracted course.