Course of infection and histopathological lesions in mice infected with seventeen Trypanosoma cruzi strains isolated from chronic patients

• Published in: Revista da Sociedade Brasileira de Medicina Tropical
• Main Authors: B R Schlemper Jr, C M Ávila, J R Coura, Z Brener
• Format: Article in Journal/Newspaper
• Language: English
• Published: Sociedade Brasileira de Medicina Tropical (SBMT) 1983
• Subjects: Trypanosoma cruzi; Cepas; Histopatologia; Camundongo; Arctic medicine. Tropical medicine; RC955-962; Arctic
• Online Access: https://doi.org/10.1590/S0037-86821983000100004; https://doaj.org/article/1dc048135167415f853186255afc7be4

Mice were infected with blood forms of 17 Trypanosoma cruzi strains recently isolated from chronic patients, which were dassified as of low, medium or high virulence on grounds of the prepatent period, parasitemia and mortality at the acute phase. A total of 212 mice were studied after 3, 6, 9 and 12 months of infection. In the chronic phase, intracellular parasites were detected in 11.0%,27.9%and 54.0,% of mice inoculated, respectively, with the low, medium and high virulent strains (r= 0.98, p < 0.005). Heart fibrosis was also related to virulence, affecting 5.7%, 11.6%and30.8% (r = 0.98, p < 0.001) of the mice inoculated with the above strains; a similar relationship was observed between intensity and frequency of the heart inflammatory reaction and the severity of infection at its early stage. Necrotizing arteritis was detected in 12.2% of the inoculated animals and this lesion was related to the infection duration rather than to strain characteristics. Inflammatory lesions and tissue parasitism were stable within the period of observation, whereas fibrosis was Progressive. The findings suggest that mice may reproduce heart lesions resembling human pathology and that organ damage apparently depends on the parasite virulence.