The pathology and pathogenesis of fatal hepatic amoebiasis—a study based on 79 autopsy cases

Abstract

The present study is based on a retrospective analysis of 79 autopsy cases of hepatic amoebiasis. An attempt has been made to reconstruct the sequence of events starting from intestinal infection to invasion and transport of amoebae along the radicles of the portal veins, the formation of early Zahn's infarct and the proliferation of amoebae in such foci leading to the formation of small abscesses. The coalescence of small abscesses gives rise to the apparently large abscesses. Apart from direct contiguity, more distant extension leading to a satellite abscess is due to involvement of the hepatic and/or portal venous radicles. It seems that obstruction of the hepatic vein contributes substantially towards the enlargement of the liver and its exaggerated nutmeg appearance. Signs and symptoms of hepatic vein obstruction sometimes overshadow the abscess pathology. Thrombosis or pressure of a neighbouring abscess over the portal vein obstruction sometimes overshadow the abscess pathology. Thrombosis or pressure of a neighbouring abscess over the portal vein and bile-duct lead to development of portal hypertension and jaundice. Both cell-mediated and humoral immunity are depressed in fatal cases of hepatic amoebiasis.