N-acetylcysteine in Non-Acetaminophen Pediatric Acute Liver Failure

Inclusion Criteria: * Meet entry criteria for and be enrolled in the Pediatric Acute Liver Failure prospective database. * Able to be evaluated and initiate treatment within the first 24 hours of hospitalization * Patients transferred from referring hospitals to the study site may be considered for enrollment, provided that no other treatment protocol has begun, and that no liver support device (BAL, extracorporeal liver assist device, transgenic pig perfusion) has been used or is contemplated. * Use of fresh frozen plasma infusions will not disqualify patients from participation. Exclusion Criteria: * older than 18 years of age * pregnancy * ALF that is secondary to acute acetaminophen toxicity, mushroom poisoning, or a known malignancy. * Patients who exhibit signs of cerebral herniation, have intractable arterial hypotension, require inotropic drugs, or demonstrate signs of sepsis (temperature ≥ 39.5o C or bacteremia) at the time of enrollment * No exclusion will be made on the basis of race, ethnic group or gender. * Criteria for inclusion of females and minorities will be those established in the NIH guidelines