Recurrent Clostridium difficile infection (CDI) is defined as the recurrence of infection after successful initial therapy. Recurrent CDI occurs up to 20% of the time after initial treatment and up to 60% after one recurrence. Fecal microbiota transplantation (FMT), the introduction of healthy donor stool into the patient’s colon via enema or colonoscopy or the upper GI tract via endoscopy, has become a promising new therapy for this debilitating disease. A new review looks at the effectiveness of FMT for CDI infections. Two, randomized control trials, 28 case-series studies, and five case reports were included, of which 516 patient were treated with FMT for recurrent CDI. Across all studies for recurrent CDI, symptom resolution was seen in 85% of cases. One trial compared FMT route (n = 20) and found a resolution rate of 60% in the nasogastric tube group vs 80% in the colonoscopy group although the difference was not significant (P = 0.63). The authors suggest that FMT may have a substantial beneficial effect with few short-term adverse effects for recurrent CDI. Evidence is insufficient for FMT use for refractory or initial treatment of CDI infections. They were unable to detect a difference in efficacy based on donor, preparation, or delivery method (Ann Intern Med 2015;162:630-638; doi:10.7326/M14-2693). An accompanying editorial brings up several intriguing questions about FMT, including how to regulate the procedure and donor sources (Ann Intern Med 2015;162:662-663; doi:10.7326/M15-0609).

Recently, a nonprofit called OpenBiome, based in Medford, MA, created a commercially available product with screened, filtered, and frozen material ready for clinical use. The company provides fecal microbiota preparations for both colonic and duodenal delivery. Another approach has been transplantation of nontoxigenic C. difficile strains. In a recent study, preparations of nontoxigenic C. difficile M3 (NTCD-M3) were given orally in three different concentrations, along with a placebo group, to patients with first CDI infections or recurrent CDI. Fecal colonization with the NTCD-M3 occurred in 69% of the patients in the treatment group. Recurrence of CDI occurred in 30% of placebo patients and 11% of treatment patients (odds ratio 0.28; 95% CI, 0.11-0.69; P = 0.006). Only 5% of patients receiving the highest concentration of spores had a recurrent CDI. The authors conclude that NTCD-M3 was well-tolerated and safe while significantly reducing CDI recurrence (JAMA 2015;313:1719-1727; doi:10.1001/jama.2015.3725).