Antibiotics after FMT increase long-term C. difficile recurrence rate

SAN DIEGO — Patients who receive non-Clostridium difficile infection antibiotics after successful fecal microbiota transplantation therapy have a threefold increased rate of long-term CDI recurrence, according to data presented at DDW 2016.

“In our study we aimed to understand the long-term risk of C. diff recurrence following a successful fecal microbiota transplantation,” Monika Fischer, MD, from Indiana University, told Healio Gastroenterology. “We aimed to actually answer the most commonly asked questions by our patients. These were the following: ... 'What is my likelihood of developing recurrent C. diff after a successful fecal transplant?' ... 'Will I get C. diff if I need to take an antibiotic in the future?' and ... 'If I need to take an antibiotic shall I take a prophylactic anti-C. diff antibiotic such as vancomycin with it, or shall I take a probiotic with it, or both?'"

Monika Fischer

Fischer and colleagues prospectively followed 152 patients who underwent successful FMT for recurrent CDI (73% women; mean age at FMT, 58 years; mean follow-up, 62 weeks), and completed questionnaires regarding non-CDI antibiotic use, concomitant prophylactic anti-CDI antibiotic and/or probiotic use, and CDI recurrence. The researchers confirmed questionnaire data with EMR and pharmacy records.

Overall, 58 (38%) of the patients received an antibiotic — and among them 28 (48%) used them more than once — most often to treat urinary tract infections (28%), pneumonia (21%), and sinusitis and/or upper respiratory infection (12%).

Sixteen patients experienced recurrence of C. difficile for an overall recurrence rate of 10.5%, and of these 16 patients, 63% received antibiotics and 37% did not.

Thus the antibiotic-associated rate of recurrence was 17.2%, and recurrence rate without antibiotics was 6.4%. The odds ratio associated with the increased risk for recurrence with use of antibiotics was 2.95 (95% CI, 1.04-8.39).

Among the 58 antibiotic users, 47% used prophylactic anti-CDI antibiotics (70% vancomycin, 30% metronidazole), 50% used prophylactic probiotics, 26% used both and 28% used neither.

The recurrence rate with neither was 23%, with probiotics only it was 21%, with anti-CDI antibiotics it was 0%, with concomitant anti-CDI antibiotics and probiotics it was 20%, and with concomitant anti-CDI antibiotics and/or probiotics it was 15%. The corresponding odds ratios were 0.47 (95% CI, 0.11-1.91) for prophylactic antibiotics, 1.63 (95% CI, 0.41-6.52) for probiotics and 1.29 (95% CI, 0.29-5.77) for both.

“Unfortunately, we could not make a conclusion from this study regarding the usefulness of prophylactic anti-C. diff antibiotic (vancomycin/metronidazole) or probiotic given the small sample size and the low number of recurrences on an antibiotic,” Fischer said. “However, what we could find is that the use of systemic antibiotics increased the risk of recurrence by threefold, so we can certainly tell our patients that the risk of overall recurrence is about 10% within 1 year or a year and a half following the fecal transplant. If they take an antibiotic ... the risk will go up to 17% and if they can avoid the use of systemic antibiotics, the risk is about 6%.”

More data from randomized controlled trials are needed to definitively conclude whether a prophylactic anti-CDI antibiotic or probiotic should be used, she added.

“Knowing also that vancomycin has detrimental effects on the gut microbiota, including decreasing biodiversity and increasing the primary-to-secondary bile acid ratio thus adversely affecting the bile metabolism ,” compounded by the fact that there are no proven clear benefits at this point in time, “I do not recommend the prophylactic use of vancomycin in the post-transplant setting if someone is required to take a systemic antibiotic,” she said. – by Adam Leitenberger

Reference:

Fischer M, et al. Abstract 93. Presented at: Digestive Disease Week; May 21-24, 2016; San Diego.

Disclosures: Fischer reports consulting for Rebiotix and Tetherex. Please see the DDW disclosure list for all other researchers’ relevant financial disclosures.

Editor's Note: This item has been updated with additional quotes from the presenter.