EVALUATION OF ARGENES RESEARCH USE ONLY, REAL-TIME PCR REAGENTS FOR HSV1 AND HSV2 R-GENETM

The Herpesviridae are a family of DNA viruses which are responsible for a wide spectrum of infections in humans. There are eight human Herpesviridae, of which Herpes simplex virus types 1 (HSV-1) and 2 (HSV-2) and Varicella Zoster Virus (VZV) are the most common in immunocompetent patients. Usually benign, the infections linked with these viruses can nevertheless develop severe clinical forms such as encephalitis, meningitis, retinitis and neonatal infections.  Various antivirals have proved their worth in efficiently treating these pathologies if prescribed early. Among the severe forms of HSV-1, HSV-2 or VZV infections in adults, HSV-1-induced encephalitis. At present, there is no commercially available FDA-approved kit for the HSV-1 and 2 diagnosis by polymerase chain reaction (PCR) method and molecular diagnostic laboratories must therefore develop and validate their own in-house assays.  The Argene HSV1 HSV2 VZV R-gene™ kit, a real-time PCR may provide a standardized solution to diagnose HSV1, HSV2, and VZV viral infection in clinical specimens.  In this study we evaluated the Argene HSV1 HSV2 VZV R-gene™ kit only for HSV 1 & 2 from cerebrospinal fluid (CSF) specimens and compared results of this kit with results obtained from our in-house HSV 1&2 assay.

            DNA from CSF samples (n = 40) were coded, extracted, and tested blindly in a real-time PCR assay using both methods (our in-house HSV 1 & 2 qualitative assay, Argene HSV1 HSV2 VZV R-gene™ quantification kit).  Quantification of HSV1 and HSV2 viral load was performed using a standard curve of known HSV1 and 2 DNA concentrations, the Log₁₀ results of each assay were plotted against those of the reference laboratory, and R² values calculated. 

            A strong linear relationship was identified between our in-house assay and Argene’s HSV1 HSV2 VZV R-gene™ kit. In both assay examined, clinical concordance was 100% (clinical sensitivity and specificity were both 100%).  The HSV1 HSV2 VZV R-gene™ kit gave reproducible results and this assay significantly simplified detection of HSV 1 & 2 viral infection compared to our in-house assay.  As a result of employing Argene’s HSV1 HSV2 VZV R-gene™ kit savings should be realized by eliminating much of the manual set-up required for in-house assays thereby improving turn-around time. In our opinion, the HSV1 HSV2 VZV R-gene™ kit would be suitable for use in diagnostic laboratories that do not have the facilities and staff to design and validate their own in-house assays for the molecular diagnosis of HSV1 and HSV2 DNA.