Background: PCR detection of CSF Herpes virus DNA is an important tool in the diagnosis of CNS infections. Use of this test has been shown to have an impact on patient management as measured by shortened patient stays, specific therapeutic intervention, reduction of empirical expensive therapy administration, all of which should translate into significant health care savings.
Objective: The present study aimed at implementing, and evaluating both clinically and analytically the performance of several commercially available PCR based assays for the detection of Herpes virus infections of the CNS.
Study design: A total of 314 patients with suspected CNS Herpesvirus infection were investigated, between 1999 and 2001, by Stair primers PCR. Starting on January 2002, two commercially available real-time-PCR systems were implemented and tested using the Stair primers PCR assay as golden standard and three external control proficiency panels along with serial dilutions of positive clinical samples.
Results: Sensitivity of the assay was determined to be <200 copies per ml for HSV and <1250 copies per ml for CMV. Positive results were obtained for 17 patients (6 HSV-1, 1 HSV-2, 1 EBV, 1 CMV, 6 VZV and 2 HHV-6) whose clinical and analytical findings were consistent with the PCR results. A real-time-PCR procedure was introduced in 2002 with similar sensitivity, but a more rapid response.
Conclusion: Conventional end-point PCR proved useful to the diagnosis of CNS herpes virus infection, with an impact on the clinical intervention. However, the use of Real-Time-PCR has greatly enhanced these advantages, making results available at a much earlier time, thus significantly reducing the need for empirical treatment.