Performance evaluation of the QIAstat-Dx gastrointestinal panel 2 for the detection of Clostridioides difficile against multiple commercial assays.

Acute gastroenteritis is caused by a variety of pathogens, including bacteria, viruses, and parasites, which may have overlapping clinical signs and symptoms. Community-acquired gastroenteritis is caused by various pathogens, while healthcare-associated gastroenteritis is caused by Clostridioides difficile. Current diagnostic approaches utilize C. difficile nucleic acid amplification tests (NAATs) alone or in combination with an enzyme immunoassay for C. difficile antigen and toxin. This study evaluates the analytical performance of C. difficile target detection from 290 clinical specimens using the QIAstat-Dx multiplex gastrointestinal panel (GIP) 2 compared with four commercially available NAATs (Cepheid Xpert C. difficile, BD MAX Cdiff, Verigene CDF, and BioFire GI panel) as well as the C. difficile immunoassay. The positive percent agreement (PPA) and negative percent agreement (NPA) were calculated for all assays in the study. All molecular assays demonstrated a PPA greater than 85%, and an NPA greater than 96% when compared to the other NAATs. The QIAstat-Dx GIP 2 performance was comparable to the other NAATs, demonstrating 95.0%, 88.5%, 98.1%, and 93.7% PPA and 98.2%, 96.9%, 96.6%, and 99.1% NPA compared to Cepheid Xpert C. difficile, BD MAX Cdiff, Verigene CDF, and BioFire GI panel, respectively. Overall, the QIAstat-Dx GIP 2 assay was accurate and comparable to other commercially available methods, and the short assay setup time offers an efficient laboratory stool testing workflow.IMPORTANCEClostridioides difficile infection ranges from diarrhea to severe, life-threatening pseudomembranous colitis. Clinical criteria include three or more liquid stools in 24 h, while diagnostic testing includes nucleic acid tests alone or in combination with an enzyme immunoassay for C. difficile antigen and toxin. This study evaluates the analytical performance of C. difficile detection from clinical specimens using the QIAstat-Dx multiplex gastrointestinal panel compared with four commercial assays (Cepheid Xpert C. difficile, BD MAX Cdiff, Verigene CDF assays, and BioFire GI panel) and a C. difficile immunoassay. The BioFire GI panel had the highest positive percent agreement (90-100%), followed by the QIAstat-Dx (88-98%), BD MAX (87-98%), and the Xpert assays (86-96%). The QIAstat-Dx demonstrated high positive and negative agreement with all nucleic acid tests. The short assay setup time for the QIAstat-Dx GIP 2 also offers a streamlined testing workflow.