What are the major causes of FHF?

Acetaminophen toxicity (should be directly treated with N-acetylcysteine), hepA, autoimmune (make ANA), hepB,C,D, Wilson's disease, fatty infiltrate, Reye, pregnancy. Vascular (portal thrombosis, veno-occlusion, ishemic hepatitis) Miscellanous (sepsis, heat stroke, autoimmune)