Fulminant hepatitis. An ultrastructural study.

Ultrastructural changes were observed in 23 consecutive patients who died from fulminant hepatic failure due to hepatitis B virus (4 cases), sporadic non-A, non-B (7), or paracetamol (acetaminophen) overdose (12) and in 3 patients with subacute hepatic necrosis of unknown cause. The findings are described in detail in 12 of these patients. Fatal fulminant hepatitis was characterised by massive confluent necrosis accompanied by collapse of reticulin framework and sudden drop-out of liver cells. No aetiological distinction could be made between different viral causes of fulminant hepatitis on the basis of ultrastructural pathology. Parenchymal changes in viral cases varied from reversible non-specific necrosis to irreversible changes where fragmentation of endoplasmic reticulum, mitochondria and nuclei had occurred. Differences in ultrastructural pathology between non-viral (paracetamol overdose-induced) and viral fulminant hepatitis were apparent. Modification of endoplasmic reticulum with enlarged attached polyribosomes, breakdown of plasma membrane, accumulation of cytoplasmic amorphous material and karyorrhexis and karyolysis of nuclei were the most prominent features in non-viral cases.