title: Predominance of lineage I among Trypanosoma cruzi isolates from Venezuelan patients with different clinical profiles of acute Chagas' disease.
abstract: Trypanosoma cruzi isolates from 23 acute chagasic patients from localities of Western Venezuela (state of Barinas) where Chagas' disease is endemic were typed using ribosomal and mini-exon gene markers. Results showed that isolates of the two major phylogenetic lineages, T. cruzi I and T. cruzi II, were isolated from these patients. Six isolates (26%) were typed as T. cruzi II and 17 (74%) as belonging to T. cruzi lineage I. Analysis of random amplified polymorphic DNA (RAPD) patterns confirmed these two groups of isolates, but did not disclose significant genetic intra-lineage polymorphism. Patients infected by both T. cruzi I or T. cruzi II showed different clinical profiles presenting highly variable signs and symptoms of acute phase of Chagas' disease ranging from totally asymptomatic to severe heart failure. The predominance of T. cruzi I human isolates in Venezuela allied to the higher prevalence of severe symptoms of Chagas' disease (heart failure) in patients infected by this lineage do not corroborate an innocuousness of T. cruzi I infection to humans. To our knowledge, this is the first study describing predominance of T. cruzi lineage I in a large number of acute chagasic patients with distinct and well-characterized clinical profiles.
authors.affiliation: Departamento de Biología, Universidad de Los Andes, Facultad de Ciencias, Mérida, Venezuela. nanes@ula.ve
authors.forename: Nestor
authors.initials: N
authors.lastname: Añez
authors.forename: Gladys
authors.initials: G
authors.lastname: Crisante
authors.forename: Flavia Maia
authors.initials: FM
authors.lastname: da Silva
authors.forename: Agustina
authors.initials: A
authors.lastname: Rojas
authors.forename: Hugo
authors.initials: H
authors.lastname: Carrasco
authors.forename: Eufrosina S
authors.initials: ES
authors.lastname: Umezawa
authors.forename: Anna Maria S
authors.initials: AM
authors.lastname: Stolf
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Ramírez
authors.forename: Marta M G
authors.initials: MM
authors.lastname: Teixeira
mesh_terms: D000208:Acute Disease; D000328:Adult; D000818:Animals; D014355:Chagas Disease / Q000175:diagnosis / Q000469:parasitology*; D002648:Child; D002675:Child, Preschool; D016054:DNA, Protozoan / Q000235:genetics; D005260:Female; D005819:Genetic Markers; D006333:Heart Failure / Q000469:parasitology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D010274:Parasitology / Q000379:methods; D011110:Polymorphism, Genetic; D019105:Random Amplified Polymorphic DNA Technique / Q000379:methods; D014349:Trypanosoma cruzi / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D016054:DNA, Protozoan; D005819:Genetic Markers