Epithelial Barrier Leak in Gastrointestinal Disease and Multiorgan Failure

There are a myriad of clinical conditions whose disease etiology involves leakiness of an epithelial and/or endothelial barrier.To underscore the medical usefulness of agents that can augment barrier function, the theme of this special issue, two disease areas are highlighted.The first is the phenomenon of "leaky gut" which can play relatively obvious roles in gastrointestinal diseases such as celiac disease, Crohn's disease, and ulcerative colitis.It may play less obvious roles in seemingly unrelated illnesses such as autism, diabetes and certain microbial infectious diseases.A second disease area where barrier compromise plays a major role is multi-organ failure, a major cause of death in ICUs.Multi-organ failure highlights the important effect that the immune system and oxidative stress can have on barrier elements.The use of barrier enhancing and protecting agents in nutritional feeding in ICUs should be an area of intense interest in the future.