Are outpatient Clinics and Emergency Departments A Potential Source For Acquisition of “Community-Associated” Clostridium difficile?

Background: Community-associated Clostridium difficile infection (CDI) has been defined as a case with symptom onset in the community or 48 hours or less after admission to a healthcare facility, provided that symptom onset was more than 12 weeks after the last discharge from a healthcare facility. The source of acquisition of spores in these cases is unknown.

Objective: To test the hypothesis that outpatient healthcare settings are a potential reservoir for acquisition of spores in CDI patients with no recent inpatient exposures.  

Methods:  We performed a retrospective study of all community-associated CDI cases in a VA hospital during a 4 year period to determine the proportion of cases with prior (i.e., within 12 weeks) exposure to outpatient healthcare settings. A point-prevalence culture survey was conducted to determine the frequency of contamination of high-touch surfaces in examination rooms in 6 outpatient clinics and an Emergency Department.

Results: Of 33 community-associated CDI cases, 31 (94%) had been exposed to outpatient healthcare settings in the 12 weeks prior to onset of diarrhea and 22 (67%) had received prior antibiotics. The median number of outpatient clinic visits was 5 (range, 1 to 21). Contamination of outpatient settings with toxigenic C. difficile was detected in the Emergency Department and in 4 of 6 outpatient clinics, with 9 of 55 (16%) rooms and 9 of 165 (5%) sites being contaminated. Spores were detected by broth enrichment cultures but not by direct plating, suggesting that the burden of spores on surfaces was low.

Conclusions: These results suggest that outpatient clinics and Emergency Departments could potentially be the source of spore acquisition in many cases of community-associated CDI.