787. Evaluation of Clostridioides difficile Environmental Contamination Surrounding C. difficile Patients vs. non-C. difficile Patients in Outpatient Infusion Centers
Authors: Garey Kevin W , Hengel Richard L , Ritter Timothy E , Nathan Ramesh V , Nathan Ramesh V , Schroeder Claudia P , da Costa Gabriela L Pedro , Lancaster Christopher K , Obi Engels N , Van Anglen Lucinda J 
Published: January 2021

Abstract

Background
Clostridioides difficile infection (CDI) is the most common cause of healthcare-associated infection. CDI and non-CDI patients (pts) are often treated at the same time in outpatient infusion centers (OICs). This proximity may allow horizontal transfer of spores. However, C. difficile (C. diff) spores are ubiquitous in nature and baseline contamination rates at OICs are unknown. The purpose of this pilot study was to determine toxigenic C. diff contamination in the OIC surrounding CDI pts receiving bezlotoxumab compared to non-CDI pts receiving another infusion in the same OIC before and after cleaning.

Methods
OIC contamination rates were assessed at baseline, after infusion and after cleaning the environment of CDI pts receiving bezlotoxumab compared to non-CDI pts receiving other infusions. For each pt receiving an infusion, 11 areas were sampled at each time period; the infusion chair (n=4), medical and non-medical equipment (n=3), and the floor surrounding the infusion chair (n=4). Five high traffic control areas per sampling day were included. Swabs were cultured anaerobically and PCR was used to identify toxin genes. Proportion of toxigenic C. diff positive samples were compared between CDI and non-CDI pts for each time point. Cleaning was performed using a standard protocol of bleach (CDI pt) or non-bleach (non-CDI pt) products.

Results
Samples (n=709) were obtained from 10 pts in each group (329 CDI, 330 non-CDI, 50 high-traffic) from 7 OICs over 4 months. Overall, 55 patient area cultures (8%) were positive for C. diff. Positive sampling areas were highest for floors (13%) followed by infusion chairs (7%) and equipment (4%). Baseline contamination in high traffic areas was 6%. Contamination rates (Table 1) for CDI were 7% at baseline, higher after infusion (15%) and lower after cleaning (5%). For non-CDI pts, rates were similar at baseline (8%), after infusion (6%) and after cleaning (9%).
Table 1. Proportion of toxigenic C. difficile-positive samples in the environment of CDI and non-CDI patients.

Conclusion
Compared to non-CDI pts, CDI pts had similar baseline but lower after cleaning contamination rates. These preliminary results suggest that with a proper cleaning protocol in place, the presence of CDI patients in an OIC does not increase the likelihood of C. diff transmission for other at-risk populations.

Disclosures
Kevin W. Garey, PharmD, MS, FASHP, Merck & Co. (Grant/Research Support, Scientific Research Study Investigator) Richard L. Hengel, MD, Merck & Co. (Other Financial or Material Support, Grant Steering Committee Member) Timothy E. Ritter, MD, Merck & Co. (Other Financial or Material Support, Grant Steering Committee Member) Ramesh V. Nathan, MD, FIDSA, Merck & Co. (Other Financial or Material Support, Grant Steering Committee Member) Engels N. Obi, PhD, Merck & Co. (Employee) Lucinda J. Van Anglen, PharmD, Merck & Co. (Grant/Research Support)