The potential of probiotics to prevent Clostridium difficile infection.

Exposure to antibiotics is the major risk factor for Clostridium difficile diarrhea (CDD), suggesting that impairment of colonization resistance due to depletion of the gut flora is a significant underlying disease susceptibility factor. Many properties of probiotic organisms indicate that they may be able to replenish the depleted gut flora and restore colonization resistance. However, despite numerous clinical trials, the evidence base for probiotics in the prevention of CDD remains weak. A recent large trial of a multistrain, high-dose probiotic did not show clear evidence of efficacy. The role of probiotics in the prevention of CDD remains unclear.