Poblaciones de trypanosoma cruzi altamente homogéneas en una región de baja endemia chagásica: relevancia en la patogenia de la enfermedad de Chagas en Chile / Highly homogeneous trypanosoma cruzi populations in a low endemic region for Chagas disease: importance in the pathogenesis of Chagas disease in Chile

ABSTRACT

Trypanosoma cruzi from 23 chronic and acute cases of Chagas dosease were isolated and further characterized. They displayed a remarkable similarity, after typification by schizodeme analysis using restriction endonuclease Eco Ri. All trypanosoma cruzi isolates belonged to the isoenzymatic Zymodeme 2 Bol. These findings were corroborated analyzing cases from families with demonstrated congenital transmission. The acute cases were newborns or offspring of infected mothers or patients with AIDS. All trypanosoma cruzi strains isolated in theses cases were very similar with almost identical schizodemes. Patients with AIDS had severe clinical manifestations whereas children with congenital infections had a great variety of clinical symptoms. In chronic cases, little clinical differences were observated for the different trypanosoma cruzi strains. It is concluded that there is a low correlation between the trypanosoma cruzi strain and the clinical prognosis of Chagas disease, being of greater relevance the host's genetic background and inmune response