A 36-year-old woman with neuromyelitis optica had been treated with steroids for the prevention of relapse. Both immunocompetent and immunocompromised individuals may be affected. Herpes simplex virus 2 was detected from the CSF in 10 patients, and HSV-1 in 1 patient. Samples from 110 patients, 65 of whom were diagnosed with or were strongly suspected of having HSV-2 meningitis and 45 with acute aseptic meningitis of unknown causes, were analyzed. PCR for varicella zoster virus (VZV)-DNA was positive in the cerebrospinal fluid. Combinations of meningitis/ encephalitis and myelitis/radiculitis are associated with Epstein Barr Virus (EBV); myelitis with VZV, CMV, EBV, and HSV-2; and ventriculitis/encephalitis with VZV and CMV. We could not find evidence of VZV, CMV, or HHV-6 in the pathogenesis of RALM, although most patients were previously infected by those viruses.
The sensitivity of real-time HSV-2 PCR was found to be 87% (33/38) in primary and 70% (19/27) in recurrent meningitis. The HSV-2 viral load was significantly higher in primary than in recurrent meningitis and correlated with the degree of inflammation. For example, stroke due to VZV-mediated large vessel disease (herpes zoster ophthalmicus) occurs predominantly in immunocompetent hosts, while small vessel disease (leukoencephalitis) and ventriculitis develop almost exclusively in immunocompromised patients. Real-time PCR for the diagnosis of HSV-2 meningitis was evaluated in a large, clinically well-characterized sample of material and found to identify more cases than nested PCR in the group of patients with recurrent meningitis. Quantification of DNA enables further research of disease prognosis and treatment.