GDH and toxin immunoassay for the diagnosis of Clostridioides (Clostridium) difficile infection is not a 'one size fit all' screening test. | LitMetric
Diagnosing Clostridioides (Clostridium) difficile infection is challenged by lack of a clear gold standard. We sought to determine if the two-step algorithm (screening GDH and toxin lateral flow assay followed by tcdB PCR) would have adequate clinical performance at a tertiary care center. Of 486 patients, 310 (63.8%) were immunocompromised. Of 150 PCR-positive specimens, 52 (34.7%) were toxin-positive and 126 (84.0%) were GDH positive. Positive GDH or toxin results corresponded to lower PCR cycle threshold values (P < 0.01). PCR-positive patients had more frequently documented antibiotic usage (78.4% vs 66.9%, P = 0.05) and diarrhea (91.0% vs. 79.4%, P < 0.01) and less frequent alternate etiologies of diarrhea (27.3% vs. 41.1%, P = 0.004) or laxative use (24.6% vs 36.1%, P = 0.02). Toxin positivity was associated with antibiotic use (P < 0.01), but not with neutropenia, diarrhea, malignancy, or chemotherapy (P > 0.05). The application of the 2-step algorithm should be thoroughly evaluated in immunocompromised patient populations before implementation.
For infections, highly sensitive rapid diagnostic test kits are necessary for prompt diagnose and infection control. In this study, we evaluated "Quick Chaser CD GDH/TOX" (evaluation kit), a rapid diagnostic kit for , using 65 clinical stool specimens, comparing with GE test immunochromato-CD GDH/TOX "Nissui" (GE test) and TECHLAB QUIK CHEK COMPLETE (QUIK CHEK). The results of the evaluation kit showed a high concordance rate; 100% the positive concordance rate (31/31) and 97.
species lacking toxin genes (non-toxigenic or NTCD) may confer protection against CDI. However, current diagnostic tests detect either toxin proteins or toxin genes and cannot detect NTCD. This study developed a molecular testing method that uniquely identified NTCD and assessed its prevalence in a clinical cohort.
Current guidelines recommend a two-step algorithm rather than relying solely on a single test for diagnosing infection. This algorithm starts with enzyme immunoassay (EIA) for detecting glutamate dehydrogenase (GDH) and toxins A/B, followed by nucleic acid amplification test (NAAT) for GDH-positive but toxin-negative cases. This study compared the performance of three commercial NAATs: the STANDARD M10 , Xpert , and BD MAX Cdiff assays, utilized as confirmatory testing of the two-step algorithm.
* Complications from CDI, such as pseudomembranous colitis and toxic megacolon, require prompt diagnosis through clinical evaluation, microbiological tests, and potentially imaging studies.
* Treatment typically involves halting harmful antibiotics and using specific antimicrobial therapies, with options like fidaxomicin, oral vancomycin, and fecal microbiota transplantation for recurrent cases.
Biofilm formation and toxin production are some of the virulence factors of Clostridioides difficile (C. difficile), which causes hospital-acquired C. difficile infection (HA-CDI).
