Zoster encephalitis. Isolation of virus and measurement of varicella-zoster-specific antibodies in cerebrospinal fluid.

Varicella-zoster virus (VZV) was isolated on two occasions from the cerebrospinal fluid of an elderly woman with encephalomyelitis complicating thoracic zoster. Antibodies to ZV-induced membrane antigen (FAMA) were present in cerebrospinal fluid in a titer of 1:64; serum antibodies were 64-fold higher. Further evidence for local antibody production was derived from simultaneous measurements of immunoglobulin G and albumin in cerebrospinal fluid and serum and calculation of a cerebrospinal fluid-IgG index.