Laxative use and testing for Clostridium difficile in hospitalized adults: An opportunity to improve diagnostic stewardship

Background: It is recommended that that only unformed stool from patients with diarrhea be tested for Clostridium difficile infection. We determined the prevalence of and patient characteristics associated with antecedent laxative receipt among hospitalized adults undergoing C difficile testing. Methods: In a case-control study of 5,452 C difficile tests from 5 hospitals in Southeast Michigan, patients who received laxatives (docusate, senna, polyethylene glycol 3350, bisacodyl, and magnesium hydroxide) in the 24 or 48 hours before testing were identified. Logistic regression was performed to identify patient characteristics associated with laxative receipt before testing. Results: In 535 (9.8%) and 707 (13%) tests, patients received laxatives in the 24 and 48 hours before testing, respectively. The odds of antecedent laxative receipt were significantly greater for patients residing on a surgical service than a medical service (24 hours odds ratio [OR], 2.5; 95% confidence interval [CI], 2.1-3.1; 48 hours OR, 2.7; 95% CI, 2.3-3.2), patients residing in an intensive care unit (ICU) than a non-ICU (24 hours OR, 1.3; 95% CI, 1.0-1.6; 48 hours OR, 1.3; 95% CI, 1.1-1.6), and patients whose Elixhauser Comorbidity Score was 4 or higher (24 hours OR, 1.4; 95% CI, 1.1-1.7; 48 hours OR, 1.4; 95% CI, 1.2-1.7). Conclusions: Among patients tested for C difficile, antecedent laxative use was common. Improving diagnostic stewardship around C difficile testing, particularly in surgical and ICU patients, is a significant opportunity and priority for quality improvement. (C) 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.