Experimental Chagasic Cardiomyopathy in Dogs; Clinical and Pathological Findings
P.A. Barbabosa1; CH. J.C. Vázquez1; M.R. Fajardo1; M.M. Barbosa2; V.S. Díaz-González2; C.C. Alejandri1; S.S. Lagoons1; G.F. Oaks1; F.J.G. Estrada1; B.C. Guzmán4
Chagas's disease (Tripanosoma Cruzi) infects around 10 to 18 million people in Latin America, the necessity to have an animal model in which the course of the infection and the pathology evolve from a similar way to the human disease.
A desparasited and vaccinated litter of 6 Creole dogs of 6 months of age was used, five dogs were inoculated with a culture of metacyclic Trypomastigotes Sylvio strain, donated by Dr, Nisha Garg (University of Texas Health. Galveston, Tx). Dogs were inoculated per intra-peritoneally (IP) with 75XI03.
We measured the temperature daily until the day 20 post inoculation (PI) finding slight increase of temperature starting from the day five PI until the day 17. Blood, radiographies and electrocardiograms were performed every week.
In the week two, changes in the electric axis toward the left side were observed. There were not significant changes in the hemograms. Four animals suffered sudden death to the 4 and 5 weeks PI. At necropsy it was observed hepatomegaly, splenomegaly, slight ascites, all hearts showed a severe left hypertrophic and dilated right cardiomyopathy. Histopathologically, hepatic congestion with marked hydropic change were observed, in the kidneys, glomerular congestion and interstitial nephritis were present, lungs showed congestion, in the hearts, a severe myocarditis with infiltration of mononuclear lymphocytes were present with parasites into the muscular fibers.
The findings here, revealed that is very useful the utilization of radiographies and electrocardiograms for diagnostic and estimating the evolution of Chagas's disease in dogs. As an animal model, it reproduced the same findings reported in human Chagas's disease. These results in dogs suggest that radiographies and electrocardiograms could be useful to detect this silent Chagas's disease in humans.