Difference in the incidence of Clostridium difficile among patients infected with human immunodeficiency virus admitted to a public hospital and a private hospital.

OBJECTIVE

To compare the occurrence of Clostridium difficile among inpatients infected with human immunodeficiency virus (HIV) in two different hospitals.

DESIGN

Prospective, observational study.

SETTING

Specialized HIV inpatient units.

PATIENTS: HIV-infected inpatients at Cook County Hospital (CCH) and Rush Presbyterian St. Luke's Medical Center (RPSLMC).

INTERVENTIONS: A clinical and epidemiologic assessment of patient risk factors for C. difficile was performed. C. difficile isolates found on stool, rectal, and environmental cultures were typed by pulsed-field gel electrophoresis.

RESULTS

Twenty-seven percent of patients admitted to CCH versus 4% of patients admitted to RPSLMC had positive cultures for C. difficile (P = .001). At CCH, 14.7% of environmental cultures were positive versus 2.9% at RPSLMC (P = .002). Risk factors for C. difficile acquisition included hospitalization at CCH, more severe HIV, use of acyclovir and H2-blockers, and longer hospital stay. Patients admitted to CCH were taking more antibiotics, had longer hospital stays, and more frequently had a history of C. difficile infection. During the study, two strains (CD1A and CD4) extensively contaminated the CCH environment. However, only CD1A caused an outbreak.

CONCLUSIONS

The C. difficile acquisition rate at CCH was sevenfold higher than that at RPSLMC, and CCH had a more contaminated environment. Differences in patient acquisition rates likely reflect a greater prevalence of traditional C. difficile risk factors and a concurrent outbreak at CCH. Although two strains heavily contaminated the environment at CCH, only one caused an outbreak, suggesting that factors other than the environment are important in initiating C. difficile outbreaks.