Antibiotics prescribed by dentists may be contributing to the growing problem of Clostridium difficile (C. diff) infection, which can cause severe diarrhea and even death. Many prescriptions issued by dentists are unnecessary or not recorded in medical charts, according to researchers presenting at the recent Infectious Diseases Society of America conference (IDWeek 2017) in San Diego. They recommend improved awareness by dentists of antibiotic prescription guidelines and advise better communication between dental and medical communities.
Researchers tracked patients who had experienced community-associated C. diff to determine the factors that may have led to their contracting the infection. More than half of them had been prescribed antibiotics, of which 15% were for dental procedures.
"One-third of C. diff patients who took antibiotics for a dental procedure had no mention of antibiotics in their medical chart," wrote lead study author Stacy Holzbauer, MPH, DVM, in an email interview with DrBicuspid.com. "This indicates that the primary care provider was likely not aware of the prescription. This is concerning, since the provider might not think about C. diff or other complications of antibiotic use, and treatment could be delayed."
Holzbauer is the career epidemiology field officer for the U.S. Centers for Disease Control and Prevention (CDC) and the Minnesota Department of Health (MDH).
Clostridium difficile infections are the most frequent cause of healthcare-associated diarrhea, with the most significant risk factors being antibiotic use and healthcare exposure. Antibiotics kill both good and bad bacteria in the gastrointestinal system, and inappropriate use can lead to the development of drug-resistant bacteria. C. diff is one of the top three most urgent antibiotic threats identified by the CDC, and infection can occur after just one dose of antibiotics.
According to MDH surveillance data, the most common indication for antibiotic use in community-associated C. diff cases is upper respiratory infections, followed by dental procedures. Community-associated cases are those in which patients were not hospitalized or did not stay overnight in a nursing home prior to contracting their infection.
Dentists write about 10% of outpatient prescriptions in the U.S., but data have previously been limited on the effects of dental prescriptions on C. diff. In the new study, researchers from Minnesota Department of Health, which is part of the CDC's Emerging Infections Program and monitors C. diff cases in five counties, examined medical records and data on community-associated C. diff cases to explore differences in antibiotic prescribing and documentation in cases undergoing dental procedures.
"In Minnesota, the majority of C. diff infections occur outside the hospital and are driven by antibiotic use in community or outpatient settings," Holzbauer noted.
The MDH interviewed 1,626 patients with community-associated C. diff from 2009 to 2015. Almost 1,000 of these patients had been prescribed antibiotics, and 136 of these prescriptions were for dental procedures.
The patients prescribed antibiotics for dental procedures compared with other indications were significantly older (median age 57 versus 45 years, p < 0.001), more likely to be prescribed clindamycin (50% versus 10%, p < 0.001), and less likely to be prescribed fluoroquinolones (6% versus 19%, p < 0.001) and cephalosporins (7% versus 30%, p < 0.001).
Taking any antibiotic has been found to increase the chances of C. diff infection by sevenfold, but taking clindamycin increases it twentyfold, according to Holzbauer.
Based on interviews by MDH of those who received antibiotics for a dental procedure, this prescription was not documented in the medical records of 46 cases (34%). The researchers also concluded that dental antibiotic prescribing rates are likely underestimated.
"Many times dentists are not aware of the complications that can develop from antibiotic use," Holzbauer wrote. "Better communication is needed between patients, dentists, and medical providers."
What's the difference?
According to a previous survey conducted by MDH, 36% of dentists prescribed antibiotics in situations not generally recommended by the ADA. When making decisions about prescribing antibiotics, dentists also reported difficulties, including confusion about or perceived conflicts among prescribing guidelines.
Some situations, such as treating an infection from a tooth abscess, are still thought to be appropriate for dental antibiotic prescription. However, antibiotic use before dental procedures in patients with heart conditions or artificial joints generally is no longer recommended, since the risks from taking antibiotics are thought to be greater than the risk of infection in those cases.
The following resources provide information for dentists on antibiotic prescribing:
- ADA guidelines on antibiotic prophylaxis prior to dental procedures
- American Academy of Pediatric Dentistry guidelines on antibiotic therapy in pediatric dental patients and guidelines for treating those at risk of infection
- American Association of Endodontists' guidance on the use of systemic antibiotics in endodontics and guidance on the use of antibiotic prophylaxis in patients at risk of systemic disease
- CDC's checklist for antibiotic prescribing in dentistry
- MDH's information for dentists on antibiotic resistance, prescribing, and stewardship.
Holzbauer emphasized the importance of including dentists in programs to modify antibiotic prescribing.
"Dentists have often been overlooked as major partners in programs that promote appropriate antibiotic use, and it is critical that dentists are included in efforts to improve antibiotic prescribing," she wrote.