Clostridial enterocolitis.

Equine clostridial enterocolitis is being recognized with increasing frequency. It has been identified in foals with diarrhea, antibiotic-associated enterocolitis, or nosocomial enterocolitis. The sporadic occurrence of clostridial enterocolitis, the variety of types of clostridia involved, and the difficulty of experimentally reproducing the disease suggest that it is a poorly defined multifactorial syndrome. The risk factors associated with susceptibility to colonization and progressive infection are largely based on anecdotal observations and extrapolation from human studies. Quantitative studies are needed to decipher the complex interactions between host and indigenous microflora that provide for and maintain a healthy colonization resistance environment. It seems that such studies might be more beneficial in furthering our understanding of the pathogenesis of clostridial enterocolitis than attempting to implicate another agent or toxin as the sole cause of the disease in equids. Treatment protocols that interrupt the pathogenesis of the disease need to be devised and critically evaluated to complement the present protocols emphasizing supportive care. Perhaps it is time to consider clostridial enterocolitis as yet another consequence of the use of antimicrobials analogous to the selective pressures that result in the emergence of multiple drug-resistant pathogens.