Study: C. Diff Cases Tied to Antibiotics for Dental Work

The rise in community-acquired Clostridium difficile appeared to be at least partly fueled by a surprising source -- dentists, according to researchers here.

Analysis of 7 years of surveillance data in five Minnesota counties found that 57% of C. difficile patients had been prescribed antibiotics, something that was assumed to be the cause of the disease, according to Stacy Holzbauer, DVM, a CDC field officer assigned to the Minnesota Department of Health in St. Paul.

But 15% of those patients were given the drugs by their dentists. In many cases that fact didn't find its way into the patient's primary care records, Holzbauer told reporters at the annual IDWeekmeeting, sponsored jointly by the Infectious Diseases Society of America (IDSA), the Pediatric Infectious Diseases Society (PIDS), the Society for Healthcare Epidemiology of America (SHEA), and the HIV Medicine Association (HIVMA).

Dentists are allowed to write prescriptions for antibiotics, and often do when they are performing oral surgery or simply for prophylaxis in some patients, Holzbauer said. Indeed, one estimate suggests they write 10% of all such prescriptions, although the guidelines of the American Dental Association say that relatively few patients need such treatment.

Holzbauer said that at least part of the problem is that dentists, unlike primary care physicians, don't necessarily see the adverse effects of antibiotics, even though they might be aware of the risk in principle.

"No one goes to the dentist when they have diarrhea so [dentists] don't get the feedback," she said.

It's also not clear that dentists are routinely included in discussions about the risks of antibiotics, she said, adding they might be in a "blind spot in the antibiotic stewardship conversation."