Days of antibiotic spectrum coverage (DASC) as predictors of recurrent Clostridioides difficile infection: A retrospective cohort study

Background: Broad-spectrum antibiotic use increases the risk of Clostridioides difficile infection (CDI), with recurrence rates varying by antibiotic type, spectrum, and treatment duration. We assessed CDI recurrence risk using the days of antibiotic spectrum coverage (DASC) score, considering antibiotic spectrum and use duration. Methods: We retrospectively analyzed patients with hospital-acquired CDI. A logistic regression analysis was used to evaluate CDI recurrence, incorporating three variables: DASC score prior to CDI diagnosis, type of anti-CDI drugs, or DASC score after CDI diagnosis. Results: Overall, 246 patients were included, with 31 (12.6 %) cases of recurrence. Median DASC scores within 30 days prior to CDI diagnosis were higher in the recurrent group than in the non-recurrent group (128 [interquartile range: 106-217] vs. 80 [interquartile range: 39-142], p < 0.01). Using the lowest quartile of DASC scores as the reference, the analysis indicated higher relative risks of CDI recurrence in the upper quartiles. However, daily DASC scores post-CDI diagnosis did not correlate with recurrence. Compared to metronidazole, fidaxomicin lowered the risk of CDI recurrence (relative risk 0.2, 95 % confidence interval: 0.1-0.8, p = 0.03). Conclusions: The DASC score within 30 days prior to CDI diagnosis appears to be a predictive risk factor for CDI recurrence.