C. Diff Screening at Admission Can Cut Hospital- Acquired Infection

Detecting and isolating Clostridium difficile (C. diff) carriers upon admission to the hospital can a significantly decrease the incidence of health care-associated C. diff infection (HA-CDI), according to a study published in the June issue of JAMA Internal Medicine. The authors say C. diff screening upon admission is an easily implemented and effective strategy for preventing HA-CDI. It is estimated that there are half a million cases of C. diff in the United States annually, causing 29,000 deaths. But, current control measures do not target asymptomatic carriers, despite evidence that they can contaminate the hospital environment and cause health care-associated infection.

The Québec Heart and Lung Institute had endemic C. diff infection, despite “significant” efforts to control it. So, in 2013 the facility adopted a policy to detect and isolate asymptomatic carriers. The present study reports the effects of implementation. The intervention of screening asymptomatic patients admitted through the emergency department occurred Nov. 19, 2013, through March 7, 2015. Identified carriers were placed under infection control measures similar to those for C. diff infection, but tailored to minimize the effect on bed management and work flow. Admission screening was conducted to test for the tcdB gene using polymerase chain reaction on a rectal swab (BD GeneOhm Cdiff Assay; BD Diagnostics). A pre-intervention control period was defined as an epidemic period (Aug. 22, 2004 to July 21, 2007) and a post-epidemic period (July 22, 2007 to Nov. 18, 2013).

The researchers found that 92.5 percent of 8,218 eligible patients were screened. Of those screened, 4.8 percent (n=368) were identified as C. diff carriers. During the intervention period significantly fewer patients developed an HA-CDI—38 patients during the intervention (3.0 per 10.000 patient-days) versus 416 patients (6.9 per 10.000 patient-days) during the post-epidemic, pre-intervention period. The change in the level of HA-CDIs significantly decreased overall, through a gradual progressive decrease over time (7 percent per 4-week period). The researchers estimated that the intervention prevented 63 of the 101 expected HA-CDI cases (62.4 percent). In total, 121 patients needed to be screened and six asymptomatic carriers needed to be isolated to prevent one HA-CDI. Preliminary data shows this strategy may be cost-effective. The intervention cost $130,000 over 17 periods and prevented approximately 63 cases. Each HA-CDI case costs between $3,427 and $9,960, so the intervention’s presumable savings ($216,000 to $627,000) were greater than the costs of the intervention.

“Prevalence of carriage on admission was similar to that in other investigations, suggesting that our screening strategy was adequate to identify carriers,” writes lead author Yves Longtin, M.D., from Jewish General Hospital in Canada. “To date, no commercial test is approved in Canada or the United States to detect asymptomatic carriers, and the optimal detection method is unknown.”