Revista da Sociedade Brasileira de Medicina Tropical
On-line version ISSN 1678-9849
CAMANDAROBA, Edson L.P. et al. Trypanosoma cruzi: susceptibility to chemotherapy with benznidazole of clones isolated from the highly resistant Colombian strain. Rev. Soc. Bras. Med. Trop. [online]. 2003, vol.36, n.2, pp. 201-209. ISSN 1678-9849. http://dx.doi.org/10.1590/S0037-86822003000200002.
The present investigation was performed to evaluate the susceptibility of seven clones isolated from the highly resistant Colombian strains, prototype of Biodeme Type III. Seven clones previously obtained, showed a phenotypic homogeneity and high similarity with the parental strain. Eight groups of 30 mice were inoculated with one of seven clones or the parental strain; 20 were treated with benznidazole (100mg/kg/day) and 10 were untreated controls. Cure evaluations were done by parasitological and serological tests and PCR. Cure rates varied from 0% (null) to 16.7%. Correlation between positivity of parasitological and serological tests with positive PCR reached 37%. The results demonstrated the high resistance of the clones, suggesting the predominance of a highly resistant principal clone in this strain. The findings apparently indicate that the possibility of cure is minimal for patients infected with this biodeme; a fact that could affect the control of Chagas' disease through treatment of chronically infected people.
Keywords : Chagas' disease; Trypanosoma cruzi; Clones; Chemotherapy; Resistance; Benznidazole.