Evaluation of a non-isotopic polymerase chain reaction assay for detection in clinical specimens of herpes simplex virus type 2 DNA

Background: PCR assays for detection of herpes simplex virus DNA sequences in clinical specimens are more sensitive than cell culture.

Objective: A non-isotopic PCR assay (glycoprotein B HSV-2 assay, Roche Molecular Systems) for detection of HSV-2 DNA sequences was evaluated on 234 clinical specimens.

Study design: A total of 125 patients (73 women, 40 men, 12 unknown) provided 162 samples contained in viral transport medium. Samples were first inoculated in cell culture, centrifuged at 12 000 × g, lyzed and kept frozen. A total of 77 women provided 42 cervicovaginal lavages and 30 vaginal tampons that were lyzed, tested with two isotopic HSV-2 PCR assays and kept frozen. All these samples were subsequently thawed and amplified with the glycoprotein B HSV-2 assay using generic primers for HSV glycoprotein B gene. Amplicons were captured on microplates with a HSV-2-specific probe and were detected with avidin-peroxidase and substrate.

Results: Of the 162 samples submitted to viral culture, HSV-2 was isolated from 73 while 89 did not contain HSV-2. All the 73 specimens with culture-proven HSV-2 infections tested positive with glycoprotein B HSV-2 assay (sensitivity of 100%). Herpesviruses other than HSV-2 were isolated from 34 samples that were negative with glycoprotein B HSV-2 assay. Two culture-negative samples tested positive in the glycoprotein B HSV-2 assay (specificity of 98.7%). The latter samples could not be retested in confirmatory isotopic HSV-2 PCR tests. HSV-2 DNA sequences could also be detected directly in cervical lavages or vaginal tampons from 13 women with the glycoprotein B HSV-2 assay.

Conclusion: Detection and typing of HSV-2 in clinical samples, including those collected in viral transport medium, can be accomplished with PCR assays using the AMPLICOR format.