Fulminant hepatic failure, metabolic encephalopathies

Prompt referral for liver transplantation is the therapy of choice for most patients with fulminant hepatic failure. Transplantation should be considered in all cases in which the patient demonstrates progressive clinical deterioration (encephalopathy, hypoglycemia, metabolic acidosis, renal failure, and coagulation defects)." Patients should be transferred at the first sign of altered mental status, because these patients often worsen very rapidly. One-year smvival rates with liver transplantation for fulminant hepatitis are 50% to 80% (as compared to <20% with medical management alone)."... 

B. After 24-48 hours, when transaminase levels (AST and ALT) begin to rise, hepatic necrosis becomes evident. If acute fulminant hepatic failure occurs, death may ensue. Encephalopathy, metabolic acidosis, and a continuing rise in the prothrombin time (PT) indicate a poor prognosis. Acute renal failure occasionally occurs, with or without concomitant liver failure. 

Provide general supportive care for hepatic or renal failure if it occurs. Emergency liver transplant may be necessary for fulminant hepatic failure. Encephalopathy, metabolic acidosis, hypoglycemia, and progressive rise in the prothrombin time are indications of severe liver injury. 

B. Hepatic failure. Liver injury may be apparent within 24-36 hours, with rapidly rising transaminase levels. Fulminant hepatic failure may follow, with jaundice, encephalopathy, and death. Encephalopathy, metabolic acidosis, severe coagulopathy, and hypoglycemia are grave prognostic signs and usually predict a fatal outcome. 

However, encephalopathies with a metabohc basis tend to be the most problanatic for infants or children, with functional outcomes dependent upon timely and pradent interventions. Three varieties of metabolic encephalopathy in children are discussed here. The first two are closely related. Inborn (genetic) errors of metabolism can present in the newborn as severe encephalopathy from hyperammonemia alone. When a metabolic error presents months to years later, a degree of hepatic insufficiency may complicate the metabolic derangement. In acute or fulminant hepatic failure of any etiology (i.e., infections, drug-induced, toxin-related), the rise in serum ammonia may be only moderate but other factors contribute to the ensuing encephalopathy, which may be devastating within days. 

Schnittger, C., Weissenborn, K., Boker, K., Kolbe, H., Dengler, R., Manns, M.R 1997. Continuous noninvasive cerebral perfusion monitoring in fulminant hepatic failure and brain oedema. In Advances in Hepatic Encephalopathy Metabolism in Liver Disease, eds C. Record and H. A1 Mardini (eds.)., pp. 515-519. New Castle upon Tyne Medical Faculty of the University of Newcastle upon Tyne... 

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