L. Clifford McDonald
Newly released practice guidelines for Clostridium difficile infection, or CDI, in both adults and children include changes in diagnostics and antibiotic therapy.
The guidelines, published in Clinical Infectious Diseases by the Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA), also call for fecal microbiota transplantation (FMT) to fight the infection in certain cases.
“We can better control this epidemic by learning how to use new treatments and diagnostics,” L. Clifford McDonald, MD, co-chair of the guidelines panel and associate director for science at the CDC’s Division of Healthcare Quality Promotion, said in a news release. “The role of the infectious disease specialist is critical, not only in providing expert diagnosis and treatment of C. difficile infections, but also in helping set institutional policies that will lead to their prevention, including reducing the inappropriate use of antibiotics through good stewardship.”
Each year in the United States, CDI affects about 500,000 people and kills 15,000 to 30,000. The rate of CDI incidence in the U.S. reached a high in 2010 and has not decreased since then, like it has in parts of Europe.
Opinions on how best to diagnose CDI vary. However, the new guidelines recommend testing only patients with new-onset and unexplained diarrhea, defined as three or more unformed stools over 24 hours.
In addition, although most hospital labs now use molecular diagnostic testing, it is highly sensitive and can result overdiagnosis. Therefore, when an institution has no predetermined criteria limiting testing to those with significant unexplained diarrhea, the guidelines recommend a C. difficile common antigen test and stool toxin test as parts of a diagnostic process.
The guideline authors also addressed the need to avoid unnecessary antibiotic use because not everyone who has C. difficile requires treatment.
“We often find people get better on their own if they stop taking the offending antibiotic,” McDonald said.
Almost all antibiotics create a risk for CDI, but those of greater concern include fluoroquinolones, cephalosporins and clindamycin.
For cases in which antibiotics are needed, the guidelines have changed recommendations for first-line drugs. Instead of metronidazole — the previously recommended first-line therapy — the authors now suggest using vancomycin or Dificid (fidaxomicin, Merck). The latter two agents have had higher cure rates in studies, the authors concluded.
The guidelines also recommend FMT for patients with two or more recurrences of CDI and for whom traditional antibiotics have not been effective. The FDA has not approved FMT, the process of transferring bacteria from a healthy person’s stool to a patient with CDI in order to replace “good” bacteria and control the disease. But the agency has issued guidance for its use when standard CDI therapy fails. – by Joe Green
McDonald reports no relevant financial disclosures. Please see the guidelines for all other authors’ relevant financial disclosures.