What is the likelihood of a relapse with clostridium difficile infections?

Common: There is a small percentage of c. Dificile infections that recur so it does happen. However with newer treatments it happens less. You may want to look into sarcomyces boullardi[(forgive me if mispelled) or florastor which for a long time was used in europe to treat c. Dif infections...With huge success. Check out your local healthfood store; or ask your doctor for more info.

Perhaps 10%: But if a relapse occurs once, more relapses are common.

20-30%: C. Difficile infections are not generally hard to treat and more than 90% initially respond well to vancomycin or Metronidazole treatment. The problem is the high rate of relapse after treatment of 20-30%. The risk of future relapses increases after each relapse. Relapses are treated with a tapering and pulse course of vancomycin. Multiple relapses may require a fecal transplant -cures 91%.