Histopathology of hepatic amoebiasis in guinea-pigs infected through intracaecal and intramesenteric routes.

The comparative histopathological details of amoebic liver abscess were studied following intracaecal and intramesenteric inoculation of Entamoeba histolytica into guinea-pigs. The histological changes of amoebic liver abscess formed via the former route were similar to those seen in man. These consisted of a central necrotic area with few lymphomononuclear cells and E. histolytica trophozoites at the periphery of the lesion. The amoebic liver abscess formed via the intramesenteric route, however, differed from that formed by intracaecal inoculation in three ways: (i) in having an intense inflammatory reaction, (ii) healing of the abscess by fibrosis and (iii) exhibiting a giant cell reaction.