Liver Retransplantation

Hepatic allograft failure continues to be a serious risk for the liver transplant recipient. 8 Because no effective method of extracorporeal support is currently available for these patients, hepatic retransplantation provides the only available option for patients in whom an existing graft has failed, and accounts for 10-20% of all liver transplants. The need for retransplantation can occur as the result of four principle causes — primary nonfunction, rejection, disease reoccurrence, or as a result of technical complications. These four diagnoses comprise almost 90% of liver retransplants. A diagnosis of primary non-function is a diagnosis of exclusion made if a graft never shows evidence of initial function and its dysfunction cannot be attributed to technical or other causes. By a more stringent definition, PNF is defined as graft dysfunction in the first week post transplant leading to patient death or retransplantation. In practice, this latter definition may be too limited as there is a spectrum in the degree of initial graft failure that may extend out to a month post transplant. These late initial failures (from 7-30 days) have been referred to by some as delayed non-function. The clinical syndrome accompanying initial non-function is also quite variable. In its most dramatic form, it is characterized by a constellation of findings in many ways analogous to fulminant hepatic failure; including a profound hepatic dysfunction accompanied by severe hypoglycemia, deep hepatic coma, renal failure, no bile output, marked coagulopathy, acidosis, and shock. Cerebral edema and elevated intracranial pressures are also possible. Initial graft failure can also present with a more indolent course, as a slow and inexorable loss of function with a rising bilirubin, a gradually worsening coagulopathy, and poor bile production. (Table E6.1)

If a graft fails secondarily, following initial evidence of good function, the cause usually represents either rejection, disease reoccurrence, or technical causes (such as vascular thrombosis and less frequently, complications of biliary reconstruction). Factors that support a decision to retransplant a patient for rejection include: 1) chronic rejection that is not likely to be reversible as shown by massively elevated liver function enzymes or a biopsy showing the disappearance of bile ductules, arteriolar thickening, and extensive periportal fibrosis; 2) the persistent elevation of serum bilirubin which is unresponsive to multiple courses of immu-nosuppression; or 3) poor liver function that deteriorates even further when im-munosuppression is reduced to maintenance levels. Rejection is the most common reason for retransplantation in adults while technical failure is the predominant cause of retransplantation in the pediatric population. Primary non-function is the second most common reason for retransplantation in adults and the least common cause in children.

Disease reoccurrence, especially with regard to hepatitis C (the most common reason for primary transplantation) is a growing cause for considering retransplantation. Recent analysis of large data sets of liver recipients indicates

0 0

Post a comment