Clostridium difficile infection (CDI) is a common and sometimes fatal healthcare–associated infection. It manifests as diarrhea that often recurs and can progress to toxic megacolon, sepsis, and death. “The incidence, mor­tality, and healthcare costs resulting from CDIs in hospitalized patients have reached historic highs,” says L. Clifford McDonald, MD, FACP, FSHEA. “CDI often occurs in patients in healthcare settings where antibiotics are prescribed and symp­tomatic patients are concentrated.”

From 2000 to 2009, the number of hospitalized patients with any CDI discharge diagnoses more than doubled; the number with a primary CDI diagnosis more than tripled. “While the incidence of other healthcare-associated infections has declined, the incidence of CDI has increased,” Dr. McDonald says. Evidence-based guidelines are available for preventing CDI in hospitals, but the degree to which adherence to these guidelines can effectively help prevent these infections is unknown.

Analyzing the Impact of CDI

In the March 13, 2012 Morbidity & Mortality Weekly Report, Dr. McDonald and colleagues published a study that sought to identify healthcare exposures for CDI, determine the pro­portion of CDI occurring outside hospital settings, and assess whether prevention programs can effectively reduce CDI. The research team analyzed population-based data from the Emerging Infections Program as well as present-on-admission and hospital-onset, laboratory-identified CDI events that were reported to the National Healthcare Safety Network (NHSN).

When analyzing data from the Emerging Infec­tions Program, 10,342 CDIs were identified. “Overall, 94% of all CDIs were related to various precedent and concurrent healthcare exposures,” says Dr. McDonald. “About three-fourths of CDIs had their onset occur outside of hospitals [Figure 1]. It should also be noted that some cases occurred in patients who were exposed to multiple settings, so these estimates might not completely reflect the overall impact of C. difficile.” Of note, 44% of infections were in patients aged 65 and older. According to death certificates, more than 90% of all deaths from CDI occur in this age group.

While the incidence of other healthcare-associated infections has declined, the incidence of CDI has increased.

The NHSN data involved reporting from 711 acute care hospitals in 28 states. Dr. McDonald and colleagues observed 42,157 incident laboratory-identified CDI events  in this data, with 52% of these events already being present on admission to hospitals (Figure 2). The pooled rate of hospital-onset CDI was 7.4 per 10,000 patient-days, with a median hospital rate of 5.4 per 10,000. Hospitals with 200 or fewer beds accounted for 61% of laboratory-identified CDIs that were reported. Furthermore, nearly one-third of hospitals (31%) that reported these infections were from institutions that had medical school affiliates.

Taking Infection Control Precautions

Much of the recent increase in the incidence and mortality of CDI can be attributed to the emergence and spread of a hypervirulent, resistant strain of C. difficile, according to Dr. McDonald. “This strain produces greater quantities of prin­cipal virulence toxins A and B and has additional factors enhancing its virulence,” he explains. “Despite this new strain, many of these infections can still be prevented. In analyses of three state prevention programs conducted over about 21 months, findings demonstrated a 20% reduction in the incidence of hospital-onset CDI. These programs involved simple infection control precautions that can be universally applied at hospitals nationwide.”

According to the CDC, effective strategies to prevent CDI include improving antibiotic use, early and reliable detection of CDI, isolation of symptomatic patients, and reducing C. difficile contamination of healthcare environmental sur­faces. “Good antibiotic stewardship is an important aspect to preventing CDI,” says Dr. McDonald. “Antibiotic use significantly increases the risk for developing CDI for up to 2 months after antibiotics are discontinued. To prevent transmission of C. difficile, early detection and isolation of patients with CDI is essential. Glove use—with strict adherence to changing between patient contacts—is another important method to preventing contamination with C. difficile from symptomatic patients.”

Being More Proactive in CDI Prevention Efforts

The CDC and other infectious disease organizations provide tools for facilities to develop antibiotic stewardship programs, but Dr. McDonald says more needs to be done to prevent CDIs across all healthcare settings. “Clinicians, inpatient and outpatient healthcare facilities, public health officials, and partner patient safety organizations could all benefit from increased collaboration in preventing CDI. These collaborations could broaden and enhance the use of prevention strategies. Considering that healthcare reform is placing greater emphasis on improving patient safety and reducing costs, now is an opportune time to take the steps that are required to eliminate healthcare–associated CDIs and reduce the burden of these infections in the future.”