Histopathology of Listeria monocytogenes after oral feeding to mice.

Ingestion by mice of Listeria monocytogenes in drinking water induced micro-abscesses of the liver and ulcerative enteritis. In pregnant mice, these lesions were larger and more extensive than in nonpregnant female and male mice. Pregnancy is interrupted by a purulent panmetritis and necrotizing placentitis. The early microabscess is unique in that it consists of monocytic cells with bizarre-shaped nuclei. The experimentally induced pathological changes in livers and intestines of mice used in this study are similar to those observed in listeric neonatal septicemia of human infants.