Liver transplantation in patients with liver failure related to exertional heatstroke.

Background & Aims: Severe acute liver injury is a grave complication of exertional heatstroke. Liver transplantation (LT) may be a therapeutic option, but the criteria for LT and the optimal timing of LT have not been clearly established. The aim of this study was to define the profile of patients who require transplantation in this context.

Methods: This was a multicentre, retrospective study of patients admitted with a diagnosis of exertional heatstroke-related severe acute liver injury with a prothrombin time (PT) of less than 50%. A total of 24 male patients were studied.

Results: Fifteen of the 24 patients (median nadir PT: 35% [29.5-40.5]) improved under medical therapy alone and survived. Nine of the 24 were listed for emergency LT. At the time of registration, the median PT was 10% (5-12) and all had numerous dysfunctional organs. Five patients (nadir PT: 12% [9-12]) were withdrawn from the list because of an elevation of PT values that mainly occurred between day 2 and day 3. Ultimately, 4 patients underwent transplantation as their PT persisted at <10%, 3 days (2.75-3.25) after the onset of exertional heatstroke, and they had more than 3 organ dysfunctions. Of these 4 patients, 3 were still alive 1 year later. Histological analysis of the 4 explanted livers demonstrated massive or sub-massive necrosis, and little potential for effective mitoses, characterised by a "mitonecrotic" appearance.

Conclusion: The first-line treatment for exertional heatstroke-related severe acute liver injury is medical therapy. LT is only a rare alternative and such a decision should not be taken too hastily. A persistence of PT <10%, without any signs of elevation after a median period of 3  days following the onset of heatstroke, was the trigger that prompted LT, was the trigger adopted in order to decide upon LT.

Lay Summary: Acute liver injury due to heatstroke can progress to acute liver failure with organ dysfunction despite medical treatment; in such situations, liver transplantation (LT) may offer a therapeutic option. The classic criteria for LT appear to be poorly adapted to heatstroke-related acute liver failure. We confirmed thatmedication is the first-line therapy acute liver injury caused by heatstroke, with LT only rarely necessary. A decision to perform LT should not be made hastily. Fluctuations in prothrombin time and the patient's clinical status should be considered even in the event of severe liver failure.