Comparison of two assays to diagnose herpes simplex virus in patients with central nervous system infections

• Published in: Journal of clinical virology 2023-09, Vol.166, p.105528-105528, Article 105528
• Main Authors: Gaensbauer, JT, Fernholz, EC, Hiskey, LM, Binnicker, MJ, Corsini Campioli, C
• Format: Article
• Language: English
• Subjects: Central nervous system; Diagnosis; Herpes simplex virus; HSV PCR; Multiplex meningitis/encephalitis panel
• ISSN: 1386-6532; 1873-5967
• DOI: 10.1016/j.jcv.2023.105528

•In the diagnosis of herpes simplex virus central nervous system infection, targeted PCR assays had greater sensitivity than multiplex PCR assays.•The vast majority of patients tested for herpes simplex virus central nervous system infection had negative tests; 1.8% had at least one positive test.•Patients with positive targeted herpes simplex virus PCR and negative multiplex PCR had lower disease severity.•Physicians may choose to rely on multiplex PCR alone in lower risk patients, despite lower sensitivity. Multiplex PCR panels are frequently used for detecting the diagnosis of central nervous system infection, but have demonstrated lower sensitivity for herpes simplex virus (HSV) compared to targeted PCRs. Providers in our institution frequently order both multiplex (BioFire Meningitis/Encephalitis Panel (MEP)) and targeted HSV PCR (Diasorin Simplexa HSV-1/2 Direct), allowing comparison of assay performance in practice and a unique clinical characterization of patients with concordant positive or discordant results. We retrospectively analyzed all HSV testing performed using the two assays simultaneously in a large multi-center institution between 12/10/2018 and 6/6/2022. We described and compared laboratory, diagnostic and therapeutic data between patients with positive results on both assays with patients with discordant results. 1,387 patients were tested with both assays, of which 25 were positive on at least one assay. Eleven (44%) had discordant results; 9 were targeted-PCR-positive/MEP-negative and 2 were targeted-PCR-negative/MEP-positive. Compared with patients with concordant positive results, discordant targeted PCR-positive/MEP-negative patients had a higher PCR cycle threshold value (i.e., >35) and milder illness characterized by lower CSF WBC counts (4 vs 152; p = 0.032), fewer MRI abnormalities (37.5% vs. 87.5%; p = 0.039), HSV meningoencephalitis as primary discharge diagnosis (33% vs. 100%; p