Progesterone-induced amoebic liver abscess in guinea-pigs--a new model.

An experimental model of hepatic amoebiasis in guinea-pigs, simulating the natural infection in man, induced by progesterone following intracaecal inoculation of Entamoeba histolytica has been developed. On Day 3 after infection, 60% of the animals developed amoebic liver abscess, but on Days 7, 11, 15, 20 and 35 after infection liver involvement was recorded in all the animals. No animal in the control group developed hepatic amoebiasis. Severity and frequency of caecal lesions was greater in the control groups than in the experimental group receiving progesterone injections. The antiamoebic antibody levels were slightly higher in the experimental group as compared to the control group.