The following is the summary of “Diagnostic accuracy of rapid one-step PCR assays for detection of herpes simplex virus-1 and -2 in cerebrospinal fluid: a systematic review and meta-analysis” published in the December 2022 issue of Clinical microbiology and infections by Vaugon, et al.

The detection of herpes simplex virus types -1 and -2 (HSV1/2) in cerebrospinal fluid (CSF) as quickly and accurately as possible is crucial for proper patient care. Provide a brief overview of the diagnostic precision of commercial rapid sample-to-answer PCR tests (results in less than 90 minutes, without a separate nucleic acid extraction step for HSV1/2 detection in CSF.  From the beginning of 2012 to the end of 2022, researchers combed through 5 conference abstract datasets and 4 databases (MEDLINE, EMBASE, Scopus, and CENTRAL). Studies that met the criteria for diagnostic accuracy supplied enough information to build a typical diagnostic accuracy 2 by 2  table. Patients who have been diagnosed with meningitis or encephalitis. 

Provides results from the FilmArray Meningitis-Encephalitis Panel with the Simplexa HSV 1 & 2 Direct Kit polymerase chain reaction(PCR). A gold standard for real-time polymerase chain reaction assays. Data was extracted, bias was analyzed, and quality was rated by 2 researchers using QUADAS-2 in a blinded fashion. Using Bayesian random effects models, researchers combined the various estimates of accuracy. There were a total of 9924 samples from 31 investigations (27 FilmArray and 4 Simplexa) with a total of 95 HSV-1 and 247 HSV-2 infections. The pooled FilmArray had a sensitivity of 84.3% (95% credible interval [CrI]: 72.3-93.0) and a specificity of 92.9% [CrI: 82.0-98.5%] for HSV-1 and HSV-2, respectively; the corresponding values for the latter were 99.8% [CrI: 99.6-99.9%] and 99.9% [CrI: 99.9-100]. The pooled sensitivity for Simplexa was 97.1% (95% confidence interval [CrI], 88.1-99.6), while the specificity was 98.9% (95% CrI, 96.8-99.7). The combined sensitivities of FilmArray for HSV-1 and HSV-2 favored industry-sponsored research by a factor of 10.0 and 13.0, respectively. 

The potential for prejudice was frequently obscured by insufficient reporting. Several FilmArray investigations were disqualified because they failed to adequately report false-negative results. Based on their  findings, it appears that Simplexa is reliable for detecting HSV1/2 in CSF. Because of FilmArray’s moderate sensitivity for HSV-1, further testing and/or repeat CSF sampling may be necessary when the HSV-1 result is negative, even in cases of suspected HSV encephalitis. Summary estimates were not as reliable as individual estimates due to the low prevalence of HSV-1 infections. Due to missing data, researchers were unable to fully investigate the potential for heterogeneity.