Organ Transplantation, 2nd edition, edited by Frank P. Stuart, Michael M. Abecassis and Dixon B. Kaufman. ©2003 Landes Bioscience.

fulminant hepatic failure. Hepatitis E is a common cause of ALF during pregnancy in India but is not seen in the United States. A recent survey of 295 cases in the U.S. (Table 9.1) showed acetaminophen intoxication as a leading cause, followed by nonA-nonE (also termed cryptogenic) and drug-induced failure.2 Acetaminophen toxicity was associated with the best spontaneous survival (60%), and it is important to recognize its etiologic role in patients with either underlying alcohol consumption or with poor food intake, in whom lower daily doses (4 grams rather than 10-12 grams) may induce severe liver injury. The cause of nonA-nonE fulminant hepatitis remains elusive. Although a transmissible agent has been implicated, hepatitis C, hepatitis G or TTV (transfusion-transmitted virus) have been shown not to be the culprits. Drug-induced hepatic failure has a particularly poor prognosis and spontaneous survival is rare once encephalopathy develops.

Clinical evidence of intracranial hypertension include, hyperventilation, opisthotonus, hyperpronation-adduction of the arms, cardiac arrhythmia, myoclonus, seizures, poorly reactive pupils.

Patients with ALF present initially with vague symptoms, such as anorexia and malaise. Attention by patients and their caregivers may not focus on the diagnosis of liver failure until jaundice is evident. Patients often describe a syndrome suggestive of and consistent with a viral illness. When jaundice is identified, liver function tests typically reveal massive elevations in AST and ALT, elevated bilirubin, significant elevation in the PT, and, in some patients, metabolic acidosis. If Tylenol overdose is suspected, acetaminophen levels should be obtained and the patient should be started on IV acetyl cysteine (Mucomyst). A delay in diagnosis may lead to referral of a patient with ALF late in the clinical course, resulting in advanced cerebral edema.

Table 9.1. Etiology of fulminant hepatic failure in the United States2

Spontaneous N % Survival (excludes death or transplantation)

Acetaminophen 60 20% 60%

Hepatitis nonA-E 44 15% 10%

Drug-induced 33 12% 10%

Hepatitis B 30 10% 15%

Hepatitis A 21 7% 35%

Miscellaneous 122 Wilson's disease, acute fatty liver of pregnancy, Budd-Chiari Syndrome mushroom intoxication, ischemic injury, tumor infiltration, autoimmune hepatitis, rare viruses (herpes, adenovirus).

Total of series 295

Fulminant hepatic failure typically affects young individuals who had previously been in a perfect state of health and, prior to the availability of liver transplantation, was associated with 80 to 90 percent mortality, especially in patients who progressed to grade 3 or 4 hepatic encephalopathy. With successful transplantation, >90% of patients survive.3 Although many factors contribute to the deterioration and death of these patients, the terminal event is typically brainstem herniation as a result of progressive brain swelling. Hepatic encephalopathy is typically divided into 4 stages. Furthermore, coma in stages 3 and 4 is subdivided into 4 grades.(Table 9.2).

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