Low-Dose Antibiotics Effective in Treating C. Difficile

Lower doses of vancomycin encouraged by antimicrobial stewardship programs were just as effective as higher doses in treating Clostridium difficile infection, a study found.

Low doses of oral vancomycin are just as effective in treating Clostridium difficile infections (CDI) as are high doses of the antibiotic, researchers at Montefiore Medical Center and Albert Einstein College of Medicine of Yeshiva University have found.

Prescribers have been encouraged to use low doses of oral vancomycin to treat CDI since the introduction of antimicrobial stewardship programs. To test this treatment approach, the researchers compared the efficacy of low and high dose oral vancomycin in treating CDI in a hospital setting. They presented their findings on September 10, 2013, at the 53rd Annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

The study enrolled 197 patients treated with low doses (at most 500 mg per day) and 103 treated with high doses (more than 500 mg per day) of oral vancomycin after a diagnosis of diarrhea associated with CDI at Montefiore Medical Center between 2006 and 2010. All patients were aged 18 or older and had received the antibiotic for at least 72 hours. Medical records were analyzed for information on demographics, clinical parameters, in-hospital mortality, 30-day readmission rates, and any additional antibiotics given to participants.

The results indicated that patients treated with low doses of oral vancomycin had similar outcomes to those treated with high doses of the antibiotic. After 72 hours of treatment, clinical improvement was observed in 85% of patients who received low doses and 86% of patients who received high doses. When patients were discharged or ended treatment, 93% of low-dose patients and 96% of high-dose patients saw clinical improvement. Low-dose and high-dose patients also had rates that were not statistically different for in-hospital mortality (15% and 23%), retreatment (4% and 6%), and 30-day readmission for any cause (34% and 24%) and for CDI in particular (12% and 5%). Low-dose and high-dose patients also spent similar amounts of time in the hospital.

“This study's comparable results in low dose and high dose antibiotic treatment of CDI reinforce the importance of considering new approaches to using these medications,” said study author Philip Chung, PharmD, MS, clinical pharmacy manager in infectious diseases at Montefiore Medical Center and assistant professor of medicine at Albert Einstein College of Medicine, in a press release. “Antibiotic stewardship is an important focus in hospitals today. We are using our study findings to develop treatment guidelines that encourage low dose treatment.”

The authors of the study note that using low doses of oral vancomycin instead of high doses could potentially decrease the costs associated with CDI treatment in hospitals.