[Seroprevalence and vertical transmission of Chagas disease in a cohort of Latin-american pregnant women in a tertiary hospital in Madrid]

Abstract

Background: Chagas disease, caused by Trypanosoma cruzi (T. cruzi), is endemic in Latin-America and is emerging in Spain due to immigration. The vertical transmission rate is around 5%. A routine prenatal screening with serology of all pregnant women from endemic areas is recommended to identify infected newborns, allowing early treatment and cure.

Objective: The aim of this study was to estimate the prevalence of positive Chagas serology in a cohort of pregnant women from Latin-America and its vertical transmission.

Patients and methods: An observational, prospective, follow-up study was conducted on women with positive serology to T. cruzi, as well as their newborns, from January 2013 to April 2015. Congenital Chagas was ruled out using a PCR technique at birth and at 1 month, and with serology at 9-12 months old. A child was considered infected when PCR was positive, and uninfected when PCR was negative, and/or it had a negative serology.

Results: Screening was performed on 1244 pregnant women from Latin-America, and there were positive results in 40 (prevalence 3.2%, 95% CI: 2.4-4.4%), with 85% of them from Bolivia. There was only one infected newborn (rate of vertical transmission 2.8% (95% CI: 0-15%)), who had a positive PCR at birth. Relative studies enabled an 8-year-old sister with an asymptomatic disease to be diagnosed and treated. Both were treated successfully with benznidazole (later the PCR and serology were negative).

Conclusion: Screening during pregnancy in Latin-American women helped to detect those with Chagas disease. The rate of vertical transmission was 2.8%, in keeping with literature. Screening led to the detection and treatment of previously unidentified familial cases.

Keywords: Chagas disease; Cribado prenatal; Enfermedad de Chagas; Prenatal screening; Transmisión vertical; Vertical transmission.