Light microscopic findings of liver biopsy specimens from patients with hepatitis type A and comparison with type B.

We compared the light microscopic features of liver biopsy specimens taken within 15 days of onset of symptoms from 17 patients with serologically verified hepatitis type A and 10 patients with serologically verified hepatitis type B. On admission, patients with hepatitis type A experienced higher serum transaminase concentrations and lower total serum bilirubin concentrations than patients with type B. On examination of H & E preparations, specimens from both type A and type B displayed simultaneous hepatocellular degeneration, parenchymal and portal tract inflammatory cell infiltration, and sinusoidal lining cell activation. Hepatitis type A was characterized by conspicuous, mononuclear inflammatory cell infiltration of the portal tract with frequent disruption of the limiting plate, and periportal hepatocyte focal necrosis with virtual sparing of parenchyma about the central vein tributary. Specimens from 10 patients also displayed mild cholestasis. In contrast, hepatitis type B was characterized by modest portal tract infiltration, and extensive parenchymal changes and infiltration, particularly about the central vein tributary.