C. difficile Colonization Risk Elevated in Frail Patients

Hospitalized patients who have previously had Clostridium difficile (C. difficile) infection are at an increased risk of colonization if they are considered frail, according to a new study from the UK. Researchers from the Brighton and Sussex Medical School explained that after the National Health Service (NHS) of England and Wales changed their C. difficile infection preventative guidelines in 2008, infection prevalence was decreased.

Hospitals improved their cleaning and antimicrobial stewardship, but the decline in cases has now stagnated, according to the study. Most of the C. difficile cases stem from patient-to-patient transmission. The researchers decided to investigate how hospitalized patients may infect one another and establish if identifying the risk factors could be used to target infection control interventions.

Elderly medicine ward patients were recruited for the study within 24 hours of their admission, and were scored on tests for Waterlow (risk of pressure sores), MUST (risk of malnutrition) and Barthel (activities of daily living). Stool samples were collected from patients with diarrhea. Of the 727 patients across three wards included in the study, 410 patients had at least one stool sample test positive for C. difficile.

Of those 410 patients, 10% were carriers of toxigenic C. difficile on testing of their baseline sample. The researchers determined that patients who carried C. difficile were much more likely to have a previous diagnosis of symptomatic C. difficile infection, to have been a hospital inpatient in the previous three months and were more frail, according to MUST and Barthel scores, compared to non-C. difficile carriers.

On the other hand, carriers and non-carriers were similar in age, gender, comorbidities, and were no more likely to have been admitted from residential care, the researchers wrote. There appeared to be no correlation between treatment at hospital admission with antibiotics, corticosteroids, or proton pump inhibitors and C. difficile colonization. The carriers were no more likely than non-carriers to have diarrhea at hospital admissions.

Three C. difficile carriers and two non-carriers developed a clinically diagnosed infection during their hospital stay. The median length of hospital stay for patients who submitted at least one stool sample was 17 days. All cause mortality at 90 days was higher in carriers than non-carriers (37.5% vs. 20%, respectively). Independent risk factors for mortality at 90 days included male gender, prior admission from a residential home, burden of comorbid disease, and nutritional state by MUST score. Frail patients are a “potential reservoir for transmission in [a] hospital,” the study authors wrote.

“Even in a non epidemic setting toxigenic C. difficile is commonly carried by elderly hospitalized patients," the study reads. "Given that overall one fifth of our patients had diarrhea, targeted screening and isolation of patients who have previously had C. difficile infection, who have recently been in hospital and who have a MUST score of greater than or equal to 2 should be evaluated as a cost effective intervention to reduce the burden of symptomatic C. difficile infection in hospitalized patients.” The article, titled “Toxigenic Clostridium difficile colonization among hospitalised adults; risk factors and impact on survival,” was published in the Journal of Infection.