Nosocomial C. difficile Common in Pneumonia Patients

VIENNA — The three major guideline-recommended, empiric antibiotic strategies for community-acquired pneumonia are associated with similar rates of nosocomial acquisition of Clostridium difficile, according to a prospective, observational study.

The nosocomial C. difficile acquisition rates documented in the Dutch study—11.2% overall and 7.2% for the more worrisome toxigenic strains—are far from inconsequential. In the United States, with an estimated 1 million hospital admissions annually for community-acquired pneumonia (CAP), the toxigenic-strain acquisition rate extrapolates to 72,000 new carriers of toxigenic C. difficile per year, Dr. Anke H. Bruns said.

Of 107 Dutch patients hospitalized with severe CAP, 41% were treated with moxifloxacin, 44% with beta-lactam monotherapy, and the rest with beta-lactam/macrolide combination therapy. Participants were followed for 30 days, with stool samples collected on admission, 5 days later, 3 days after completion of antibiotic therapy, and on day 30, reported Dr. Bruns of University Medical Center Utrecht (the Netherlands).

Infectious Diseases Society of America guidelines recommend either of two antibiotic regimens as first-line treatment for CAP patients: monotherapy with a fluoroquinolone or combination therapy with beta-lactam and macrolide. Dutch guidelines recommend monotherapy with a fluoroquinolone or beta-lactam, or beta-lactam with a macrolide or fluoroquinolone. Dr. Bruns and her coworkers found that the regimens are equal in associated risks of acquiring C. difficile colonization.

Another key study finding was that the prevalence of C. difficile carriage at admission was 9.4%. “Most of these patients were asymptomatic, and therefore they constitute an important reservoir for the spread of disease, especially because skin contamination was also involved in several cases,” she said.

In a multivariate analysis, the parameters strongly associated with C. difficile carriage were the use of intravenous antibiotics for more than 7 days (associated with a 3.9-fold increased risk), hospitalization within the previous 3 months (4.1-fold increased risk), and tube feeding (4.4-fold increased risk).

The study has several major clinical implications, Dr. Bruns noted. No one antimicrobial proved to be linked with increased risk for emergence of C. difficile, which argues against banning any specific agent. Instead, according to Dr. Bruns, it makes more sense to implement strategies aimed at reducing overall antibiotic use in CAP patients.

The other take away point is that hospitalized CAP patients have a roughly 1-in-10 baseline prevalence of C. difficile carriage. Routine screening and institution of appropriate hygiene measures are worth considering, Dr. Bruns said.

Disclosures: Dr. Bruns disclosed having no financial conflicts regarding the CAP study.

The prevalence of C. difficile carriage at admission was 9.4%.

Source DR. BRUNS