National point prevalence of Clostridium difficile in US health care facility inpatients, 2008

Background

Recent published estimates of Clostridium difficile infection (CDI) incidence have been based on small numbers of hospitals or national hospital discharge data. These data suggest that CDI incidence is increasing.

Methods

We conducted a point prevalence survey of C difficile in inpatients at US health care facilities. The survey was developed, received Institutional Review Board approval, and was then distributed to all Association for Professionals in Infection Control and Epidemiology, Inc (APIC) members. They were asked to complete the survey on 1 day between May 7 and August 29, 2008, reporting the number of inpatients with CDI or colonization and facility-specific information.

Results

Personnel at 648 hospitals completed the survey; this represents approximately 12.5% of all US acute care facilities. All but 3 states and the District of Columbia were represented (mean, 14 facilities per state; range, 2-43). Eighty-two percent reported that their CDI rate had not decreased in the past 3 years. Respondents reported 1443 C difficile-colonized/infected patients among 110,550 inpatients; the overall C difficile prevalence rate was 13.1 per 1000 inpatients (94.4% infection). Detailed data were provided on 1062 (73.6%) patients. Of these, 55.5% were female, 69.2% were >60 years of age, 67.6% had selected comorbid conditions, 79% had received antimicrobials within 30 days, and 94.4% were detected by enzyme immunoassay. The majority of patients (54.4%) were diagnosed ≤48 hours of hospitalization, but 35% had been admitted to a long-term care facility within 30 days, and 47% had been hospitalized within 90 days; 73% met Centers for Disease Control and Prevention criteria for health care-associated CDI. Most facilities (>90%) used contact isolation for CDI patients. Bleach was used for environmental disinfection more commonly during CDI outbreaks than during nonoutbreak periods.

Conclusion

Our survey documents a higher C difficile prevalence rate than previous estimates using different methodologies. The majority of inpatient CDI appears to be health care associated. Given that not all patients with diarrhea are tested for CDI and that most facilities use enzyme immunoassays with limited sensitivity to detect C difficile, these are minimum estimates of the US health care facility C difficile burden.

Key Words: Health care-associated infection, cross infection, nosocomial infection, Clostridium difficile, Clostridium difficile infection, prevalence