title: Urbanization of congenital transmission of Trypanosoma cruzi: prospective polymerase chain reaction study in pregnancy.
abstract: Chagas disease ranks among the world's most neglected tropical diseases and congenital transmission is increasingly responsible for urbanization of Chagas disease in non-endemic areas. Molecular assays for amplification and profiling of parasite minicircle DNA (kDNA) and identification of discrete typing units (DTUs) were prospectively conducted in bloodstream and placental samples from pregnant women cursing chronic Chagas disease residing in Buenos Aires city. Sensitivity of kDNA-PCR increased from 75.6% to 95.6% when one to three sequential blood samples were analysed. Congenital infection (CI) was diagnosed in 3 neonates born to kDNA-PCR positive mothers, one who had transmitted CI in a previous gestation, pointing to family clustering of congenital transmission. Fourteen of 44 placental samples were kDNA-PCR positive, all from non-CI transmitting women, indicating that placental PCR is not useful for CI diagnosis. Placental PCR positivity was not related to maternal bloodstream PCR positivity and placental parasitic subpopulations not observed in bloodstream were detected by minicircle signatures. PCR targeted to intergenic regions of spliced-leader genes and serological tests using trypomastigote small surface recombinant antigens showed predominance of DTU group TcII/V/VI and only one patient infected with TcI. To our knowledge, this is the first PCR-based follow-up study of bloodstream and placental T. cruzi infections during pregnancy, including identification of DTUs. kDNA-PCR assays in serial blood samples provided high sensitivity for detection of T. cruzi DNA in pregnant women with chronic Chagas disease.
authors.affiliation: Laboratorio de Biología Molecular de la Enfermedad de Chagas, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET), Ciudad Autónoma de Buenos Aires, Argentina.
authors.forename: Margarita
authors.initials: M
authors.lastname: Bisio
authors.forename: María Elena
authors.initials: ME
authors.lastname: Seidenstein
authors.forename: Juan M
authors.initials: JM
authors.lastname: Burgos
authors.forename: Griselda
authors.initials: G
authors.lastname: Ballering
authors.forename: Marikena
authors.initials: M
authors.lastname: Risso
authors.forename: Rosa
authors.initials: R
authors.lastname: Pontoriero
authors.forename: Marcelo
authors.initials: M
authors.lastname: Moreau
authors.forename: Jaime
authors.initials: J
authors.lastname: Altcheh
authors.forename: María Susana
authors.initials: MS
authors.lastname: Leguizamón
authors.forename: Hector
authors.initials: H
authors.lastname: Freilij
authors.forename: Marta
authors.initials: M
authors.lastname: Marceillac
authors.forename: Alejandro G
authors.initials: AG
authors.lastname: Schijman
mesh_terms: D000328:Adult; D001118:Argentina / Q000453:epidemiology; D015153:Blotting, Western; D014355:Chagas Disease / Q000453:epidemiology* / Q000235:genetics / Q000635:transmission*; D002908:Chronic Disease; D018105:DNA, Kinetoplast / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D010922:Placenta Diseases / Q000453:epidemiology / Q000469:parasitology*; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D015597:Pregnancy Complications, Parasitic / Q000453:epidemiology / Q000235:genetics; D011446:Prospective Studies; D014349:Trypanosoma cruzi / Q000235:genetics / Q000472:pathogenicity*; D014507:Urbanization
chemical_list: D018105:DNA, Kinetoplast