Comparison of multiplex syndromic panel tests with conventional methods in the detection of gastroenteritis agents

We aimed to evaluate the performance of multiplex polymerase chain reaction (PCR)-based FTD gastroenteritis kit (Fast-Track Diagnostics, Esch-sur-Alzette, Luxembourg) and QIAstat-Dx gastrointestinal panel (Q-GP; Hilden, Germany) in the detection of different enteric pathogens.

The molecular test results of 320 stool samples from patients with a preliminary diagnosis of infectious gastroenteritis between July 2019 and October 2023 were retrospectively examined, and compared with conventional test results.

A single pathogen was detected in 144 samples, and more than 1 pathogen was detected in 22 samples with FTD and QIAstat-Dx GP. Salmonella was isolated by culture in 30% samples that were detected as Salmonella-positive by PCR. Shigella, Campylobacter, verotoxin producing Escherichia coli, Shiga-like toxin producing E. coli, enteropathogenic E. coli, enteroaggregative E. coli, and enterotoxigenic E. coli were detected by molecular tests; but could not be isolated in stool culture. Rotavirus was detected by PCR in 11.1% samples; antigen test was positive in 20% samples that were adenovirus-positive based on molecular tests. Five percent of the samples in which C. difficile was detected by molecular tests were determined to be toxin A/B positive by immunochromatographic test. G. lamblia trophozoites were seen in direct microscopic evaluation in samples that were identified as G. lamblia positive by PCR.

The multiplex gastrointestinal pathogen panel test is a simpler and faster test than traditional microbiology methods. However, the effect of these test results on the patient`s diagnosis and treatment needs to be investigated. More studies are needed to compare standard and molecular methods.