Virological diagnosis of herpes simplex encephalitis

Background: The herpes simplex encephalitis (HSE) represents one of the mos t severe infectious diseases of the central nervous system. As effective an tiviral drugs are available, rapid and reliable diagnosis has become import ant. Objectives: To evaluate retrospectively the usefulness of polymerase c hain reaction (PCR) as well as serological procedures for the diagnosis of HSE. Study, design: 631 cerebrospinal fluids (CSF) from patients with clini cal suspicion of encephalitis were tested for type-specific herpes simplex virus (HSV) DNA using PCR. Virus-specific antibodies including their intrat hecal synthesis were measured in 624 CSF and 2409 serum samples of 2711 pat ients suspected of having encephalitis. Results: Positive results were obta ined by PCR in eight patients (1.3%) for HSV-1 and in seven (1.1%) for HSV- 2, Intrathecal antibody synthesis was estimated in 24 (3.8%) patients. In g eneral, no intrathecal antibodies could be measured in patients with positi ve PCR results and vice versa the intrathecal immune response became positi ve when CSF was cleared from the HSV. Results of the antibody detection in serum specimens revealed an active HSV infection in 268 out of 2367 patient s (11.3%). Conclusions: The detection of HSV-DNA by PCR is the method of ch oice for diagnosis of HSE in the early phase of the disease. During the lat er stage, it has to be diagnosed by the estimation of intrathecally synthes ized antibodies. (C) 2000 Elsevier Science B.V. All rights reserved.