Identification of Trypanosoma cruzi Discrete Typing Units (DTUs) in Latin-American migrants in Barcelona (Spain)

Trypanosoma cruzi, the causative agent of Chagas disease, is divided into six Discrete Typing Units (DTUs): TcI–TcVI. We aimed to identify T. cruzi DTUs in Latin-American migrants in the Barcelona area (Spain) and to assess different molecular typing approaches for the characterization of T. cruzi genotypes. Seventy-five peripheral blood samples were analyzed by two real-time PCR methods (qPCR) based on satellite DNA (SatDNA) and kinetoplastid DNA (kDNA). The 20 samples testing positive in both methods, all belonging to Bolivian individuals, were submitted to DTU characterization using two PCR-based flowcharts: multiplex qPCR using TaqMan probes (MTq-PCR), and conventional PCR. These samples were also studied by sequencing the SatDNA and classified as type I (TcI/III), type II (TcII/IV) and type I/II hybrid (TcV/VI). Ten out of the 20 samples gave positive results in the flowcharts: TcV (5 samples), TcII/V/VI (3) and mixed infections by TcV plus TcII (1) and TcV plus TcII/VI (1). By SatDNA sequencing, we classified the 20 samples, 19 as type I/II and one as type I. The most frequent DTU identified by both flowcharts, and suggested by SatDNA sequencing in the remaining samples with low parasitic loads, TcV, is common in Bolivia and predominant in peripheral blood. The mixed infection by TcV–TcII was detected for the first time simultaneously in Bolivian migrants. PCR-based flowcharts are very useful to characterize DTUs during acute infection. SatDNA sequence analysis cannot discriminate T. cruzi populations at the level of a single DTU but it enabled us to increase the number of characterized cases in chronically infected patients. Fil: Abras, Alba. Universidad de Barcelona; España. Universidad de Girona; España. Barcelona Centre for International Health Research; España Fil: Gállego, Montserrat. Universidad de Barcelona; España. Barcelona Centre for International Health Research; España Fil: Muñoz, Cármen. Hospital de la Santa Creu i Sant Pau; España. Universitat Autònoma de Barcelona; España Fil: Juiz, Natalia Anahí. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina Fil: Ramirez Gomez, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina Fil: Cura, Carolina Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres” ; Argentina Fil: Tebar, Silvia. Universidad de Barcelona; España. Barcelona Centre for International Health Research; España Fil: Fernández Arévalo, Ana. Universidad de Barcelona; España. Barcelona Centre for International Health Research; España. Hospital de la Santa Creu i Sant Pau; España Fil: Pinazo, María Jesús. Barcelona Centre for International Health Research; España Fil: de la Torre, Leonardo. Barcelona Centre for International Health Research; España Fil: Posada, Elizabeth. Barcelona Centre for International Health Research; España Fil: Navarro, Ferran. Universitat Autònoma de Barcelona; España. Hospital de la Santa Creu i Sant Pau; España Fil: Espinal, Paula. Hospital de la Santa Creu i Sant Pau; España Fil: Ballart, Cristina. Universidad de Barcelona; España. Barcelona Centre for International Health Research; España Fil: Portús, Montserrat. Universidad de Barcelona; España Fil: Gascón, Joaquim. Barcelona Centre for International Health Research; España Fil: Schijman, Alejandro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina