SURGICAL ANTIBIOTIC-PROPHYLAXIS AND CLOSTRIDIUM-DIFFICILE TOXIN POSITIVITY

Objective: To examine a possible relationship between prophylactic ant ibiotic therapy (PAT) and the development of Clostridium difficile tox in (CDT) positivity. Design: Retrospective case-control study. Setting : Tertiary care medical center in New York, NY. Patients: A total of 3 57 patients, admitted from November 1992 to April 1994, with positive CDT assays. Of these, 23 patients (6%) received only PAT for elective surgical procedures. Thirty-nine patients were matched as controls for age, sex, and surgical procedure. Main Outcome Measures: Both CDT pos itivity and inappropriate use of PAT. Results: Appropriate PAT was use d in 26 (42%) of 62 patients (17% cases, 56% controls). The Mantel-Hae nszel estimator for the summary odds ratio for the development of CDT positivity from inappropriate use of PAT was 5.1 (95% confidence inter val, 1.10 to 23.64). Mean duration between the operation and the final antibiotic dose was significantly longer in the CDT-positive group co mpared with the control group (3.1 vs 1.7 days, P<.05). The length of hospital stay was significantly longer in the CDT-positive group compa red with the control group (16.5 vs 10.2 days, P<.05). Conclusions: Th e prolonged use of PAT in elective surgical cases increases the risk o f developing CDT positivity. The appropriate use of PAT could signific antly reduce health costs by eliminating unnecessary doses of antibiot ics, by decreasing the rate of CDT positivity, and by shortening the h ospital stay. Restrictive policies may need to be implemented to preve nt further antibiotic misuse.