With respect to factors during the treatment of the initial infection, patients were more likely to have a recurrence if they received a new gastric acid–suppressing agent (a proton pump inhibitor or histamine H2 receptor blocker) (HR, 1.36) or had more days of fluoroquinolone exposure (1.24).
Finally, with respect to factors after completing treatment of the initial infection, patients were more likely to have a recurrence if they received a high-risk antibiotic (HR, 2.95), received a fluoroquinolone (HR, 1.56), or received intravenous vancomycin (HR, 1.45).
Discussing the study’s limitations, Dr. Dubberke noted that the investigators relied on the hospital database to identify cases of C. difficile recurrence. "We likely missed recurrences that were diagnosed and managed as outpatients," he acknowledged. "However, conversely, the recurrences that were identified were presumably more severe in that these patients ended up having another contact with our hospital, either in the emergency room" or through direct admission.
Dr. Dubberke disclosed that he has received research funding from Optimer Pharmaceuticals, ViroPharma, Merck, and Sanofi Pasteur, and that he has been a consultant to Optimer, Merck, Pfizer, and Sanofi Pasteur. The study was supported by Optimer.