Recurrent brainstem encephalitis associated with herpes simplex virus type 1 DNA in cerebrospinal fluid

A 47-year-old man had recurrent signs and symptoms of brainstem encephalitis over a 4-year period. Although CSF viral cultures were repeatedly negative, herpes simplex virus type 1 (HSV-1) DNA was detected in CSF by polymerase chain reaction (PCR). HSV-1-specific antibodies were absent at the time of the first positive PCR test, but CSF seroconversion to high HSV-1-specific antibody titer subsequently occurred. CSF antibody to cytomegalovirus (CMV) and varicella-zoster virus (VZV) was not detectable, nor could CMV, VZV, or Epstein-Barr virus nucleic acid be detected in CSF by PCR. This is the first report of the use of CSF PCR for the rapid antemortem diagnosis of herpetic brainstem encephalitis. NEUROLOGY 1995;45: 2246-2250