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

Abstract

Introduction: 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.

Methodology: 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.

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.

Conclusions: 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.