Prevalence of Clostridium difficile colonization at admission to rehabilitation

Objectives: To assess the prevalence of intestinal colonization with Clostridium difficile (C. difficile) at admission to acute rehabilitation and to identify risk factors associated with colonization. Design: Case-control study. Participants: Consecutive admissions to 2 rehabilitation units (spinal cord injury, brain injury and stroke). Setting: Free-standing acute rehabilitation facility. Interventions: Rectal swabs for culture for C difficile were obtained at admission and cytotoxin assay performed on all culture positive specimens. Rates of colonization with cytotoxic C difficile were calculated. Charts were reviewed for medical and demographic factors that may have predisposed patients to colonization, and for possible symptoms at the time of admission. Main Outcome Measures: Percentage of patients with culture and cytotoxin assay positive for C difficile. Frequency of specific patient characteristics that could predispose to C difficile colonization. Results: Of admission stool samples, 16.4% tested positive for C. difficile; none of these patients had been identified as colonized before admission. No patients were discordant for C difficile positivity on culture and presence of a toxigenic strain. No medical or demographic factors were associated with increased risk of colonization, including age (t(52)=-.748, P=.458, not significant [NS]), diarrhea within 24 hours of admission (chi(2)(1) test=.001, P=.973 [NS]), or use of oral or intravenous antibiotics at admission (chi(2)(1) test=.044, P=.834 [NS]). Conclusions: Patients admitted to acute rehabilitation may have an elevated rate of intestinal colonization with C difficile without having clinical symptoms. No medical or demographic characteristics were found to be predictive of colonization, however, most of the patients admitted had more than I factor that may have increased their susceptibility to infection with this organism. Inadvertent transfer of this organism within the rehabilitation setting may occur because asymptornatic colonization is not recognized.