Toward Improving Early Diagnosis of Congenital Chagas Disease in an Endemic Setting

Abstract

Summary: Congenital Trypanosoma cruzi transmission is now estimated to account for 22% of new infections. Though the proportion of T. cruzi infected infants with clinical signs has fallen from the 1990s, but symptomatic congenital Chagas disease still represents a significant, albeit increasingly challenging to detect, public health problem. 3 AbstractBackground: Congenital Trypanosoma cruzi transmission is now estimated to account for 22%

Congenital Transmission of Trypanosoma cruzi in Argentina, Honduras, and Mexico: An Observational Prospective Study

“…34 A more recent study of 487 infants of T. cruzi infected mothers in Bolivia found higher numbers of false positive and borderline qPCR results. 38 Another recent study found 20.0% positive PCR on cord blood among T. cruzi seropositive mothers in Guanajuato, Mexico. 7 In Argentina, PCR positive rates as high as 30.8% in Jujuy and 27.2% in Formosa have been recently reported.…”

Congenital Chagas disease: current diagnostics, limitations and future perspectives

“…In the same two birth cohorts, the frequency of low birthweight, low Apgar scores, mortality and other clinical signs also fell significantly among uninfected infants, regardless of maternal infection status, suggesting that improvements in prognosis may have been related, at least in part, to advances in prenatal care and nutrition [20]. In a later Bolivian cohort of births from 2010-2014, 22% of T. cruzi-infected singletons had low birthweight compared to 8% of infants of uninfected mothers [18]. Twenty-nine percent of infected infants had one or more manifestations consistent with congenital Chagas disease; no severe morbidity or mortality due to T. cruzi infection was observed.…”

“…Data from prospective and retrospective observational studies as well as case reports are often interpreted interchangeably. Completeness of detection, and therefore measured incidence, will differ based on the number, type and timing of infant specimens, sensitivity of diagnostic methods and rates of follow-up at 9 months or later [17,18]. Nevertheless, factors shown to be associated with higher risk of congenital transmission include younger maternal age (believed to reflect more recent infection) [19,20], maternal and neonatal immunological responses [21,22], higher maternal parasitaemia [19,23], twin births [19], and HIV co-infection [24,25].…”

“…In T. cruzi-infected infants born between 2007 and 2016 to Bolivian women residing in Spain, the rate of symptomatic disease was 18.8% [6]. Symptomatic infants have significantly higher parasite loads, compared to their asymptomatic counterparts [18,37,38]. Congenital infection is generally assumed to carry similar long-term risk of cardiac disease as vector-borne cases, but direct data to support this assumption are lacking.…”

“…The micromethod consists of concentration of infant blood in capillary tubes by centrifugation followed by microscopic examination of the buffy coat [39]. Although the most widely used test for early detection in Latin America, micromethod fails to detect more than half of infections [18,40,41]. This technique is susceptible to differences in specimen quality and operator proficiency, with sensitivity declining with delayed sample processing; trypomastigotes become less motile over time and therefore harder to observe.…”