The contribution of radiation-induced injury to the gastrointestinal tract in the development of multi-organ dysfunction syndrome or failure

Severe damage to the gastrointestinal tract (GIT), such as Toss of mucosa and hemorrhaging following accidental overexposure to ionising radiation, appear to be a determinant feature in patient mortality. Injury to the GIT may be direct since this tissue is particularly radiation sensitive and indirect as a result of radiation burns and bone marrow aplasia. Similar to other severe trauma situations such as thermal burns or hemorrhagic shock, radiation exposure results in reduced intestinal barrier integrity which initiates and/or perpetuates inflammatory-anti-inflammatory mediator release. This may result in damage to distant organs. In this context the injured gut may be considered as a 'key player' or 'motor' in the development of Multiple Organ Dysfunction Syndrome or Failure (MODS/MOF). Of note is that radiation exposure elicits similar GIT injury of both mucosal and vascular elements as compared with other severe physical insults. Common factors are the intestinal inflammatory response and loss of barrier function. This radiation-induced response must be taken into account in intestinal responses after irradiation exposure in order to have a better knowledge of its implication in the mixed-pathology of the acute radiation syndrome. (author)