NERVOUS-SYSTEM LYME-DISEASE

Lyme disease is a multisystem infectious disease caused by tick-borne spirochetes of the Borrelia burgdorferi group. The disease occurs prim arily in specific areas of North America, Europe and Asia, reflecting the distribution of the hard-shelled lxodes ticks that are required fo r disease transmission. Diagnosis of this infection can be somewhat pr oblematic, although in clinically appropriate settings, serologic test ing can be highly useful, particularly if Western blots are used to co nfirm borderline or positive results. The organism has several specifi c organotropisms-involvement of the heart, joints and nervous system b eing particularly common. The nervous system can be involved in one or more ways. Early in infection, patients tend to get a lymphocytic men ingitis, cranial neuritis (particularly the facial nerves) or a painfu l radiculitis. Rarely, an encephalomyelitis can occur. In patients wit h more protracted and indolent involvement, a more disseminated monone uropathy multiplex may occur, or a mild, non-focal alteration of cogni tive function and memory, i.e. an encephalopathy. In patients with cen tral nervous system involvement, the most sensitive diagnostic test is the demonstration of intrathecal production of anti-Borrelia burgdorf eri antibody. Culture, polymerase chain reaction and other techniques appear to be less specific. In most instances, the disease is quite re sponsive to antimicrobial therapy. Oral treatment with doxycycline has been shown to be effective in meningitis. In more serious cases two t o four week courses of parenteral ceffriaxone or cefotaxime are effect ive in the vast majority of patients. (C) 1998 Elsevier Science B.V.