Role of Cycle Threshold in Clostridioides difficile Polymerase Chain Reaction Testing as a Predictor of Clinical Outcomes in Patients With Inflammatory Bowel Disease

Abstract Background Distinguishing Clostridioides difficile infection from colonization is challenging in patients with Inflammatory Bowel Disease (IBD). Cycle threshold (Ct), the cutoff for PCR positivity, has been investigated in non-IBD patients. Methods Patients with positive C. difficile PCR (25 IBD, 51 non-IBD) were identified retrospectively. Fifteen-day outcomes were assessed. Results Ct correlated with diarrheal days in non-IBD (P = 0.048), but not IBD patients (P = 0.769). IBD patients had shorter LOS and less severe infection, but more diarrheal days (P < 0.05). Conclusions IBD patients had a milder course but Ct results were not significant. Larger studies are needed to clarify utility of Ct in IBD.