Distribution of Trypanosoma cruzi discrete typing units in Chagas disease patients with HIV co-infection and AIDS reactivation

BISIO MMC; CURA C; DUFFY T; ALTCHEH J; GIGANTI SO; BEGHER S; SCAPELLATO PG; BURGOS JM; LEVIN MJ; SCHRECK R; FREILIJ H; SCHIJMAN AG

Revista Biomédica

Lugar: Mérida Yucatán, Mexico; Año: 2009

0188-493X

ABSTRACTNatural populations of T. cruzi are composed of multiple clones, distributed into sixphylogenetic lineages or discrete typing units, T. cruzi I and II, with 5 lowersubdivisions within T. cruzi II, believed to play a role in tissue tropism and diseasepathogenesis. The impact of HIV infection in the T. cruzi genetic diversity is ascarcely explored field of parasitology.We aimed to characterize the main parasitic lineages in clinical samples from 25patients, namely 8 infants born to 7 HIV - T. cruzi co-infected mothers, 3indeterminate chagasic patients with HIV co-infection and 7 presenting cerebralChagas due to AIDS. All tested samples were PCR positive for kinetoplastid orsatellite sequences. Out of the 7 co-infected mothers, two transmitted both HIV andT. cruzi to their siblings, four transmitted only T. cruzi. The remaining case was apregnant woman with cerebral Chagas disease who entered into a coma beingtreated with benznidazole; she did not transmit congenital Chagas disease nor HIVto her newborn.Most bloodstream populations belonged to T. cruzi IId, with unique minicirclesignatures for each patient´s strain, but identical signatures between strains frommothers and their congenitally infected infants. Mixtures of lineages were alsodetected, with differential tissue tropism of T. cruzi IIb and T. cruzi I in cerebralchagomas. Minicircle signatures showed complex patterns suggestive of polyclonalpopulations. The usefulness of molecular strategies for differential diagnosis ofChagas disease reactivation and monitoring of trypanocidal treatment is underlined.