New study challenges conventional wisdom on C. diff transmission

Although infectious disease experts long thought Clostridium difficile (C. diff) infection is primarily transmitted in healthcare settings, a new study published in the New England Journal of Medicine reveals that may not be the case.

The researchers performed whole-genome sequencing on isolates from more than 1,200 patients with C. diff infections and found:

  • Only 35 percent were related to a previous case;

  • Forty-five percent were genetically distinct from all previous cases;

  • Of the 333 patients whose symptoms were consistent with transmission, 38 percent had close hospital contact with another patient, but 36 percent had no contact with another patient in either a hospital or their community.

"Genetically diverse sources, in addition to symptomatic patients, play a major part in C. difficile transmission," the study concludes.

The results challenge the conventional wisdom on C. diff transmission, according to lead author Sahil Khanna, M.B.B.S., of the Mayo Clinic division of gastroenterology and hepatology.

"It has been believed that the typical profile of a person with C. diff is an older patient, taking antibiotics, while in the hospital," Khanna told the Mayo Clinic's news blog. "For the first time, we have described a significantly increased incidence of C. diff in children with diarrhea in a population-based cohort. Importantly, we also found that more than three-quarters of cases of C. diff in children are being contracted in the community, not in the hospital."

An August research paper in BMC Infectious Diseases identified a four-point test that could identify patients at risk of death from C. diff infections. The test involves measuring a patient's serum albumin levels, respiratory rate, c-reactive protein and white cell count. A study in the May issue of the American Journal of Infection Control similarly found testing patients with three independent risk factors could help identify 74 percent of C. diff carriers who showed no symptoms, FierceHealthcare previously reported.

To learn more:
- here's the study
- read the Mayo Clinic blog post