Heatstroke: its clinical and pathological presentation, with particular attention to the liver

Heatstroke is a potentially fatal disorder caused by an extreme elevation of body temperature. It is the most severe of the illnesses produced as a result of a high ambient temperature; however, it also may occur sporadically among individuals working or exercising in more favorable weather conditions, particularly early in their training before acclimatization occurs. The liver is a common site of tissue injury in cases of heatstroke and can be the site of fatal tissue injury in cases that survive the initial neurologic injury. Prompt early recognition of heatstroke as the entity responsible for a given patient's problems and effective early cooling with attention to expected complications can result in complete recovery in most cases. In a minority (< 10%) in whom neurologic injury has not resulted in an early death occurring within the first 2-3 days, the hepatic injury due to heatstroke can result in death that occurs a week or more after the onset of the heat stress, unless the liver is replaced. Recently, two such cases have been referred to the University of Pittsburgh for transplantation. On the basis of these two referrals and a review of the literature, we believe that this problem occurs more often than is currently appreciated, principally because of a lack of knowledge about the problem. In an attempt to correct this information deficit, this review was prepared.