Neuroborreliosis.

Neurologic manifestations of nervous system infection with Borrelia burgdorferi, Borrelia garinii, and Borrelia afzelii are qualitatively similar, and include lymphocytic meningitis, cranial neuritis, radiculoneuritis, and other focal or multifocal mononeuropathies. Parenchymal central nervous system (CNS) infection occurs rarely. Neurobehavioral changes are common, but are rarely evidence of CNS infection. Diagnosis requires likely exposure and a finding with high diagnostic positive predictive value, specifically erythema migrans, or laboratory support, typically positive 2-tiered serologic testing. CNS infection is often evidenced by a cerebrospinal fluid pleocytosis and intrathecal production of specific antibody.