{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T20:53:54Z","timestamp":1769720034085,"version":"3.49.0"},"reference-count":21,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T00:00:00Z","timestamp":1769644800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>This follow-up study expands on our previous work demonstrating that a PCR cycle threshold (Ct)\u2013guided diagnostic approach improves the management of pediatric Clostridioides difficile infection (CDI) and reduces unnecessary treatment of colonized children. We evaluated the performance of the Gastroenteritis PCR Panel by QIAstat-Dx as a standalone method in combination with the PCR cycle threshold (Ct) value in PCR-positive samples to predict the presence of free toxins. In addition, we evaluated the impact of reporting toxin production results based on PCR Ct value alongside a comment in our electronic medical record. The QIAstat-Dx assay achieved 100% sensitivity and negative predictive value (NPV), with a specificity of 69% and a positive predictive value (PPV) of 63%. When 16 false-positive samples that were co-infected with other enteropathogens were excluded, the specificity increased to 97%. We observed a significant decrease (51% vs. 68%) in the proportion of treated patients in this study compared to the pre-intervention period of our previous study (p = 0.04). In contrast, a minor, non-significant 5% increase (p = 0.60) was observed in this study compared with the post-intervention period (45% treated) from the previous study. These findings demonstrate that Ct-guided diagnostic strategies continue to enhance C. difficile diagnostic precision and help limit inappropriate antibiotic use in our pediatric population.<\/jats:p>","DOI":"10.3390\/microorganisms14020313","type":"journal-article","created":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T09:12:01Z","timestamp":1769677921000},"page":"313","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["PCR Cycle Threshold\u2013Guided Management of Pediatric Clostridioides difficile Infections"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5277-0531","authenticated-orcid":false,"given":"Mohammed","family":"Suleiman","sequence":"first","affiliation":[{"name":"Department of Pathology, Sidra Medicine, Doha P.O. Box 26999, Qatar"},{"name":"Department of Biomedical Sciences, Qatar University, Doha P.O. Box 2713, Qatar"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andr\u00e9s","family":"P\u00e9rez-L\u00f3pez","sequence":"additional","affiliation":[{"name":"Department of Pathology, Sidra Medicine, Doha P.O. Box 26999, Qatar"},{"name":"Department of Pathology and Laboratory Medicine, Weill Cornell Medicine in Qatar, Doha P.O. Box 24144, Qatar"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Neama Esmat","family":"Salieh","sequence":"additional","affiliation":[{"name":"Department of Pathology, Sidra Medicine, Doha P.O. Box 26999, Qatar"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Akorful, R.A.A., Odoom, A., Awere-Duodu, A., and Donkor, E.S. (2025). The Global Burden of Clostridioides difficile Infections, 2016\u20132024: A Systematic Review and Meta-Analysis. Infect. Dis. 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Soc."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Suleiman, M., Iqbal, M., Tang, P., and P\u00e9rez-L\u00f3pez, A. (2024). Comparison of QIAstat-Dx and BioFire FilmArray Gastrointestinal Panels in a Pediatric Population. Microorganisms, 12.","DOI":"10.3390\/microorganisms12112282"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"18730","DOI":"10.1038\/s41598-025-02526-6","article-title":"Use of PCR cycle threshold values for toxins A and B quantification in Clostridioides difficile infections","volume":"15","author":"Camenforte","year":"2025","journal-title":"Sci. Rep."},{"key":"ref_10","first-page":"44","article-title":"Clinical Impact of Clostridium difficile PCR Cycle Threshold-Predicted Toxin Reporting in Pediatric Patients","volume":"9","author":"Schwenk","year":"2020","journal-title":"J. Pediatr. Infect. Dis. Soc."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1016\/j.jinf.2017.12.001","article-title":"Potential of real-time PCR threshold cycle (CT) to predict presence of free toxin and clinically relevant C. difficile infection (CDI) in patients with cancer","volume":"76","author":"Kamboj","year":"2018","journal-title":"J. Infect."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Suleiman, M., Tang, P., Imam, O., Morales, P., Altrmanini, D., Barr, K.L., Roberts, J.C., and P\u00e9rez-L\u00f3pez, A. (2024). Use of PCR Cycle Threshold and Clinical Interventions to Aid in the Management of Pediatric Clostridioides difficile Patients. Microorganisms, 12.","DOI":"10.3390\/microorganisms12061181"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2651","DOI":"10.1128\/JCM.00563-17","article-title":"Clostridium difficile PCR Cycle Threshold Predicts Free Toxin","volume":"55","author":"Senchyna","year":"2017","journal-title":"J. Clin. 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(2017). More Pathogenicity or Just More Pathogens?\u2014On the Interpretation Problem of Multiple Pathogen Detections with Diagnostic Multiplex Assays. Front. Microbiol., 8.","DOI":"10.3389\/fmicb.2017.01210"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"10926","DOI":"10.1038\/s41598-024-60491-y","article-title":"Multiplex PCR for bacterial, viral and protozoal pathogens in persistent diarrhoea or persistent abdominal pain in C\u00f4te d\u2019Ivoire, Mali and Nepal","volume":"14","author":"Jasuja","year":"2024","journal-title":"Sci. Rep."}],"container-title":["Microorganisms"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2607\/14\/2\/313\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T09:16:41Z","timestamp":1769678201000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2607\/14\/2\/313"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,29]]},"references-count":21,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["microorganisms14020313"],"URL":"https:\/\/doi.org\/10.3390\/microorganisms14020313","relation":{},"ISSN":["2076-2607"],"issn-type":[{"value":"2076-2607","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,29]]}}}