Prediction of survival after liver transplantation by pre-transplant parameters

[Liver transplantation: indications and results]

After around 64,000 transplantations in Europe since 1988 liver transplantation has emerged as a standard treatment option for otherwise incurable chronic liver diseases. Cirrhosis of different etiologies represents the most frequent transplant indication. Overall survival in this group amounts to 72% after 5 years, and 62% after 10 years. In Germany, the main indications include alcoholic liver cirrhosis, tumors with increasing numbers in recent years, as well as viral diseases leading to cirrhosis. Since December 2006 the priority for liver transplantation is determined by the model for end stage liver disease (MELD) and not by the length of waiting time. MELD is a statistical model based on serum creatinine, serum bilirubin and coagulation, which describes the probability of 3-month mortality of a potential transplant candidate. Not all liver diseases are adequately represented by MELD necessitating the additional use of a defined number of standard exceptions that have been last updated in 2008. As a consequence of these developments indications, selection of recipients and the management of the waiting list have seen profound change.

Acute kidney injury in cirrhosis

Acute renal failure (ARF), recently renamed acute kidney injury (AKI), is a relatively frequent problem, occurring in approximately 20% of hospitalized patients with cirrhosis. Although serum creatinine may underestimate the degree of renal dysfunction in cirrhosis, measures to diagnose and treat AKI should be made in patients in whom serum creatinine rises abruptly by 0.3 mg/dL or more (>/=26.4 micromol/L) or increases by 150% or more (1.5-fold) from baseline. The most common causes of ARF (the term is used interchangeably with AKI) in cirrhosis are prerenal azotemia (volume-responsive prerenal AKI), acute tubular necrosis, and hepatorenal syndrome (HRS), a functional type of prerenal AKI exclusive of cirrhosis that does not respond to volume repletion. Because of the progressive vasodilatory state of cirrhosis that leads to relative hypovolemia and decreased renal blood flow, patients with decompensated cirrhosis are very susceptible to developing AKI with events associated with a decrease in effective arterial blood volume. HRS can occur spontaneously but is more frequently precipitated by events that worsen vasodilatation, such as spontaneous bacterial peritonitis.

CONCLUSION

Specific therapies of AKI depend on the most likely cause and mechanism. Vasoconstrictors are useful bridging therapies in HRS. Ultimately, liver transplantation is indicated in otherwise reasonable candidates in whom AKI does not resolve with specific therapy.