Recurrent Clostridium difficile infection: causality and therapeutic approaches.

Recurrent diarrhoea after successful treatment of the primary episode is a common complication of Clostridium difficile infection (CDI) and may be increasing in frequency. Evidence suggests that persistent alterations in the indigenous bowel flora and failure to mount an effective antibody response to C. difficile toxins are the main mechanisms whereby recurrent CDIs occur. Treatment of the first recurrence with the same agent used for the treatment of the primary episode is reasonable, but a different approach is needed for patients with multiple CDI recurrences. Prolonged, repeated courses of metronidazole are discouraged, but a practical first option in these patients is to use tapered-dose oral vancomycin followed by a pulsed-dose regimen. Other potential options include probiotic approaches, restoration of the normal flora, immunological approaches, toxin-binding approaches, and serial therapy with vancomycin followed by rifaximin. Randomised studies including a sufficient numbers of patients have not yet been conducted for the treatment of recurrent CDI and are needed to help guide the formulation of effective recommendations.