When patients who recovered from Clostridium difficile infection after treatment with antibiotics are given a strain of nonaggressive C. diff, it reduces CDI recurrence, according to a study in JAMA.
The nonaggressive C. diff strain doesn't produce toxins, but it does colonize patients' gastrointestinal tracts, researchers found.
Researchers randomly assigned 173 adult CDI patients to receive one of four treatments, three of which were different formulations of nontoxigenic C. diff strains called NTCD, and one of which was a placebo.
Of the 157 patients who completed the treatment, CDI recurrence was 30 percent among patients receiving placebo compared with 11 percent among all patients who received some version of the nonaggressive C. diff strain.
Researchers did not know how NTCD prevents CDI recurrence, but noted: "The most likely hypothesized mechanism of action of NTCD-M3 is that it occupies the same metabolic or adherence niche in the gastrointestinal tract as does the toxigenic C. difficile and, once established, is able to outcompete resident or newly ingested toxigenic strains."