Lyme borreliosis in Bell's palsy. Long Island Neuroborreliosis Collaborative Study Group.

Lyme borreliosis (LB) causes a range of neurologic manifestations, the most common of which is facial nerve paralysis. To evaluate nervous system LB, we organized a neurologic collaborative study group in Suffolk County, NY, a region of high LB incidence. Between July and September 1989, LB serologies were performed on all patients with new-onset Bell's palsy. Seven of 32 had serologic evidence of LB at onset. One, initially seronegative, was highly seropositive 5 weeks later. In the five in whom we examined CSF, there was no evidence of intrathecal synthesis of specific antibody. In highly endemic areas, LB may be responsible for 1/4 of cases of Bell's palsy. Rarely, the palsy may occur prior to the development of a measurable antibody response, indicating a need for follow-up serologic testing.