Treatment of relapsing Clostridium difficile diarrhoea by administration of a non-toxigenic strain.

Two patients with relapsing Clostridium difficile diarrhoea following metronidazole and vancomycin therapy were colonised with a non-toxigenic avirulent Clostridium difficile strain given orally in three doses. Both patients appeared to respond without side-effects. Oral bacteriotherapy with a defined nontoxigenic strain of Clostridium difficile would appear to represent an acceptable, alternative and novel way to treat hospitalised patients who relapse with Clostridium difficile diarrhoea after specific antibiotic therapy.