What are the risk factors that predict recurrent Clostridium difficile infections in surgical patients?

Clostridium difficile (C. difficile) infection (CDI) is a serious problem mostly studied during patients' index infections. The aim of this study is to define the incidence of primary and recurrent postoperative (postop) CDI in a single institution's entire surgical population and to identify risk factors that influence disease recurrence. Using electronic medical records from 2002 to 2012, charts were reviewed from all patients with laboratory-proven (enzyme-linked immunosorbent assay or polymerase chain reaction methods) C. difficile-positive stool samples. Index postop CDI was defined as a positive C. difficile assay (CDA) within 30 days of surgery and recurrence was defined as a positive CDA within 30 days of any surgery in a patient with a previously documented positive CDA. Patient demographics, surgical diagnoses, and laboratory data were recorded. Approximately 342,000 surgeries were performed in the study period with a 0.6 per cent (2188 patients) incidence of index postop CDI. Patients undergoing musculoskeletal surgery had the highest recurrent CDI rate [odds ratio (OR)3.09 (1.47-6.49), P = 0.003]. Use of any steroid (OR 2.45 [1.43-4.20], P = 0.002) or other immunosuppressant (OR 2.64 [1.09-6.38], P = 0.011) within six months of surgery was associated with an increased risk of the development of a recurrent CDI. Across surgical specialties at our institution, postop index CDI is low and patients have about a 5-fold increased risk for developing recurrent CDI. Patients undergoing musculoskeletal surgery are at greater risk for CDI recurrence and younger age, use of steroids and immune modulators, and surgery by organ system are independent risk factors for a recurrent CDI.