Risk Factors for the Development of Clostridium difficile-Associated Diarrhea During a Hospital Outbreak

Abstract

AbstractObjective:To evaluate the risk factors associated with a nosocomial outbreak of Clostridium difficile-associated diarrhea.Design:Case-control study with two control groups.Setting:University-affiliated urban hospital.Patients:A convenience sample of 26 patients was chosen out of a total of 78 hospitalized patients with C difficile-associated diarrhea, defined as the presence of diarrhea and a positive C difficile cytotoxin assay or stool culture. Twenty-six controls were matched for age, gender, ward, and date of admission; 18 additional controls were matched to surgical patients for date and ward of admission, as well as for the type of surgical procedure performed.Results:Significant risk factors for the development of C difficile-associated diarrhea were gastrointestinal surgery (exposure odds ratio [EOR] = 7.9, p= .004, 95% confidence interval [CI]= 1.9, 35), use of neomycin (EOR= 15.6, p=.012, 95% CI=1.7, 92), clindamycin (EOR=15.6, p=.005, 95% CI=1.7, 92), metronidazole (EOR=5.7,p=.02,95%CI= 1.4, 25), and excess antibiotic use (mean number of antibiotics = 4.2 versus 1.4, p<.00005). The presence of systemic disease and the use of antacids or immunosuppressive drugs were similar in cases and controls. In surgical patients, no specific antibiotic could be linked to C difficile-associated diarrhea because of uniform perioperative antibiotic use. There was a significant difference in the number of antibiotics administered to cases and controls (mean = 3.1 versus 1.9, p< .005).Conclusions:The results suggest that control of nosocomial C difficile-associated diarrhea may be attained by minimizing the administration of antibiotics, avoidance of high-risk antibiotics, and having a high index of suspicion of C difficile-associated diarrhea in patients who develop diarrhea after gastrointestinal surgery. Perioperative administration of metronidazole, when given with other antibiotics, failed to protect against the development of C difficile-associated diarrhea.