Persistence of Skin Contamination and Environmental Shedding ofClostridium difficileduring and after Treatment of C.difficileInfection

Abstract

Background.Current guidelines for control ofClostridium difficileinfection (CDI) suggest that contact precautions be discontinued after diarrhea resolves. However, limited information is available regarding the frequency of skin contamination and environmental shedding ofC. difficileduring and after treatment.Design.We conducted a 9-month prospective, observational study involving 52 patients receiving therapy for CDI. Stool samples, skin (chest and abdomen) samples, and samples from environmental sites were cultured forC. difficilebefore, during, and after treatment. Polymerase chain reaction ribotyping was performed to determine the relatedness of stool, skin, and environmental isolates.Results.Fifty-two patients with CDI were studied.C. difficilewas suppressed to undetectable levels in stool samples from most patients during treatment; however, 1-4 weeks after treatment, 56% of patients who had samples tested were asymptomatic carriers ofC. difficile.The frequencies of skin contamination and environmental shedding remained high at the time of resolution of diarrhea (60% and 37%, respectively), were lower at the end of treatment (32% and 14%, respectively), and again increased 1-4 weeks after treatment (58% and 50%, respectively). Skin and environmental contamination after treatment was associated with use of antibiotics for non-CDI indications. Ninety-four percent of skin isolates and 82% of environmental isolates were genetically identical to concurrent stool isolates.Conclusions.Skin contamination and environmental shedding ofC. difficileoften persist at the time of resolution of diarrhea, and recurrent shedding is common 1-4 weeks after therapy. These results provide support for the recommendation that contact precautions be continued until hospital discharge if rates of CDI remain high despite implementation of standard infection-control measures.