[Behavior of a Trypanosoma brucei strain (STIB 348C) in mice. 3. Histopathological findings in the terminal stage of infection].

Histopathological findings in the terminal stage of the infection of mice and rats with different variants of the Trypanosoma brucei brucei stock are described. Mice infected with mild variants showed after 12-149 days intense trypanosome colonization of the interstitial connective tissue, especially of the heart muscle, pancreas and choroid plexus, with severe tissue destructions, especially in the pancreas. With longer duration of the infection, round cell infiltrations of the leptomeninx and around intracerebral vessels developed. The alterations were the same in animals dying with high and low parasitemias. Some animals died with continuous bleeding from the tip of the tail, with serious effusions and massive edema or with generalized bacterial infection. The lymphatic organs showed intense reactive alterations, trypanosomes were only rarely found in lymph nodes. In the liver large fields of lymphatic and myeloid cells were seen, sometimes necroses developed. The kidneys showed marked deposition of eosinophilic material in the glomeruli and precipitation of proteinaceous material in dilated tubules. - Rats infected with mild trypanosomes exhibited intense colonization of the heart by trypanosomes, in some places many trypanosomes in lymph nodes, few trypanosomes in the pancreas. They died after a long phase of high parasitemia.--After infection with virulent parasites which killed the animals with high parasitemia in a few days, mice and rats had single small foci of trypanosome colonization of the interstitial connective tissue of heart, pancreas and choroid plexus as well as of the loose connective tissue in the hilum of the kidney and around lymph nodes.(ABSTRACT TRUNCATED AT 250 WORDS)