Liver transplantation in adults: Choosing the appropriate timing.

Liver transplantation is indicated in patients with acute liver failure, decompensated cirrhosis, hepatocellular carcinoma and rare liver-based genetic defects that trigger damage of other organs. Early referral to a transplant center is crucial in acute liver failure due to the high mortality with medical therapy and its unpredictable evolution. Referral to a transplant center should be considered when at least one complication of cirrhosis occurs during its natural history. However, because of the shortage of organ donors and the short-term mortality after liver transplantation on one hand and the possibility of managing the complications of cirrhosis with other treatments on the other, patients are carefully selected by the transplant center to ensure that transplantation is indicated and that there are no medical, surgical and psychological contraindications. Patients approved for transplantation are placed on the transplant waiting list and prioritized according to disease severity. Thus, the appropriate timing of transplantation depends on recipient disease severity and, although this is still a matter of debate, also on donor quality. These two variables are known to determine the "transplant benefit" (i.e., when the expected patient survival is better with, than without, transplantation) and should guide donor allocation.