Gino Fornaciari1, Paolo Viacava1, Mónica Esteva2, Elsa L. Segura2
2Instituto Naçonal de Diagnóstico e Investigación de la Enfermedad de Chagas, Buenos Aires. Argentina.
Giemsa staining showed in the myocardium and the esophagus some rare rounding nests, about 15-25 µm large, containing several ovular 1-2 µm formations with small nuclei, suggesting clumps of Trypanosoma cruzi amastigotes. An immunofluorescence and immunohistochemical study using antibodies anti-T. cruzi, showed intense immunoreactivity in the nests and single formations.
Ultrastructural study of the esophageal wall identified large deposits of collagen fibers and rare oval formations, 1 µm in diameter, with the following features: double peripheral membrane, microtubules of 20 nm, electrondense material of about 200 nm identifiable as nucleus, a semilunar elongated 300 X 80 nm body identifiable as kinetoplast and a cylindrical structure of 300 X 30-40 nm with more electrondense thickening at one end identifiable as axoneme with basal body.
These structures are peculiar to amastigotes of the Trypanosomatidae.
This is the first direct demonstration of this disease with its agent in South America during the early Inca civilization.