Typhlohepatitis in hamsters infected perorally with the Tyzzer's organism.

Tyzzer's organisms from a hamster case were administered perorally to 6- to 8-week-old APG hamsters and the growth of organisms and lesions produced in the intestine and the liver were studied. When cortisone was given after oral infection with 2 X 10(5) or more organisms, most animals died in 4 to 7 days showing severe necrotic lesions in the liver but no diarrhea was observed. Without cortisone, watery diarrhea was seen between 2 and 7 days after infection and some animals died in 7 to 13 days. Dead and surviving animals showed liver lesions to a lesser degree as compared to those with cortisone treatment. Two days after inoculation either with or without cortisone, a number of organisms were found within mucosal epithelial cells of the cecum and colon, and 1 or 2 days later when focal necrosis occurred in the liver, they were also found in the duodenum, jejunum and ileum. Inoculated into a ligated cecal sac, organisms were shown to multiply in epithelial cells and the lamina propria of the ligated sac, then producing hepatic lesions in 3 to 4 days when bacterial growth was not detected at any other parts of intestines, suggesting that organisms might gain access to the liver from the cecum via the portal circulation or lacteals.