Detecting Herpes Simplex Virus Using a Commercial Real-Time PCR Assay
Central nervous system infection due to the herpes simplex virus (HSV) is a medical emergency and requires a rapid diagnosis and initiation of therapy. A recent study published in the Journal of Clinical Microbiology by Matthew Binnicker, Ph.D.; Mark Espy; and Cole Irish, compared a routine real-time PCR assay for HSV type 1 (HSV-1) and HSV-2 to a recently FDA-approved direct PCR assay using 100 clinical cerebrospinal fluid samples.
Our routine real-time PCR assay is Roche HSV-57 1/2 analyte-specific reagents [ASR]; Roche Diagnostics, Indianapolis, IN. The FDA-approved direct PCR assay was Simplexa™ HSV-1/2 Direct; Focus Diagnostics, Cypress, CA. This assay does not require upfront nucleic acid extraction, and results are available in approximately 60 minutes.
Following testing of 100 clinical CSF samples, the results of the Simplexa HSV-1/2 Direct assays were compared to those of our routine method (Roche HSV-1/2 ASR), which was established as the reference standard for this evaluation.
The Simplexa HSV-1/2 assays demonstrated a combined sensitivity and specificity of 96.2% (50/52) and 97.9% (47/48), respectively, when compared to the initial results of our routine method. Further, since the Simplexa HSV-1/2 Direct assay does not require prior nucleic acid extraction and reduced the overall turnaround time approximately 4-fold (~4 h by our routine method compared to ~1 h by the Simplexa assay), this may have a significant impact on the management of patients being evaluated for central nervous system disease as a result in ~ 1 h may allow for antimicrobial therapy to be rapidly adjusted.
Read the full study for more information.