C difficile: 10% of Patients Are Carriers at Hospitalization

Lara C. Pullen, PhD

May 02, 2013

One in 10 (9.7%) patients has asymptomatic Clostridium difficile (CD) colonization at the time of hospitalization, according to a new study. The 3 main risk factors for colonization are recent hospitalization (odds ratio [OR], 2.45; 95% confidence interval [CI], 1.02 - 5.84), chronic dialysis (OR, 8.12; 95% CI, 1.80 - 36.65), and corticosteroid use (OR, 3.09; 95% CI, 1.24 - 7.73).

Surbhi Leekha, MBBS, MPH, from the Division of Infectious Diseases, Mayo Clinic, Rochester, Minnesota, and colleagues present their analysis of adults admitted to a tertiary care hospital in an article published in the May issue of the American Journal of Infection Control. Approximately half of admissions were enrolled in the study, but only 22% of admitted patients provided stool samples (n = 320).

Colonization rates were determined by polymerase chain reaction analysis of formed stool. This approach circumvented the problems associated with anaerobic cultures.

The data are consistent with a previous large, multicenter study in Canada, which demonstrated that recent hospitalization is a risk factor for CD colonization. A previous study has also demonstrated that individuals receiving chronic dialysis are at risk for CD infection. This is the first study, however, to demonstrate that corticosteroid use is a risk factor for CD colonization.

The authors note that although CD epidemiology has changed during the past decades, the risk factors for infection appear to be unchanged.

"We propose that elucidation of risk factors for CD colonization could help identify asymptomatic individuals for targeted surveillance in selected hospital settings such as high endemicity despite the use of other control measures or epidemic situations. Potential infection prevention measures to prevent CD transmission from asymptomatically colonized patients include contact precautions, hand hygiene with soap and water, and environmental cleaning with a sporicidal agent. In our population, by targeting those with identified risk factors, we would need to screen approximately half of those patients with anticipated stays >24 hours, to identify three-fourths of those colonized with C difficile," the authors write.

The authors have disclosed no relevant financial relationships.

Am J Infect Control. 2013;41:390-393. Abstract