RESUMEN
We aimed to measure the association between Trypanosoma cruzi infection in pregnancy and reduced fetal growth in the absence of T. cruzi congenital transmission. We conducted a cross-sectional study of secondary data of all singleton live births between 2011 and 2013 in five hospitals from Argentina, Honduras, and Mexico. We excluded newborns with T. cruzi infection. Noninfected pregnant people were those without any positive rapid tests. The main study outcomes were birth weight, head circumference, and length for gestational age and sex. Logistic regression models were adjusted for country, age, education level, and obstetric history. Of the 26,544 deliveries, 459 (1.7%) pregnant people were found by rapid tests to be positive for T. cruzi. Of these, 320 were positive by enzyme-linked immunosorbent assay and 231 had a positive polymerase chain reaction (PCR) test. Uninfected newborns from T. cruzi-infected pregnant people were more likely to have birth weights below the 5th and 10th percentiles and head circumferences below the 3rd and 10th percentiles. Among T. cruzi-infected pregnant people diagnosed by PCR, the odds ratios were 1.58 for birth weight below the 10th percentile (95% CI, 1.12-2.23) and 1.57 for birth weight below the 5th percentile (95% CI, 1.02-2.42). Higher T. cruzi parasitic loads in pregnancy had a stronger association with reduced fetal growth (both in birth weight and head circumference), with an odds ratio of 2.31 (95% CI, 1.36-3.91) for a birth weight below the 5th percentile. The association shows, irrespective of causality, that newborns of pregnancies with T. cruzi have an increased risk of reduced fetal growth. We recommend further studies to assess other potential confounders and the causality of these associations.
Asunto(s)
Peso al Nacer , Enfermedad de Chagas , Trypanosoma cruzi , Humanos , Femenino , Embarazo , Enfermedad de Chagas/transmisión , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/congénito , Estudios Transversales , Honduras/epidemiología , Argentina/epidemiología , Trypanosoma cruzi/aislamiento & purificación , Adulto , México/epidemiología , Recién Nacido , Complicaciones Parasitarias del Embarazo/epidemiología , Masculino , Adulto Joven , Retardo del Crecimiento Fetal/epidemiología , Retardo del Crecimiento Fetal/parasitología , Desarrollo FetalRESUMEN
Activated monocytes/macrophages that produce inflammatory cytokines and nitric oxide are crucial for controlling Trypanosoma cruzi infection. We previously showed that uninfected newborns from T. cruzi infected mothers (M+B- newborns) were sensitized to produce higher levels of inflammatory cytokines than newborns from uninfected mothers (M-B- newborns), suggesting that their monocytes were more activated. Thus, we wondered whether these cells might help limit congenital infection. We investigated this possibility by studying the activation status of M+B- cord blood monocytes and their ability to control T. cruzi in vitro infection. We showed that M+B- monocytes have an upregulated capacity to produce the inflammatory cytokine TNF-α and a better ability to control T. cruzi infection than M-B- monocytes. Our study also showed that T. cruzi-specific Abs transferred from the mother play a dual role by favoring trypomastigote entry into M+B- monocytes and inhibiting intracellular amastigote multiplication. These results support the possibility that some M+B- fetuses may eliminate the parasite transmitted in utero from their mothers, thus being uninfected at birth.
RESUMEN
Trypanosoma cruzi, the causative agent of Chagas disease, exhibits a high genetic variability and has been classified into six discrete typing units (DTUs) named TcI through TcVI. This genetic diversity is believed to be associated with clinical characteristics and outcomes, but evidence supporting such associations has been limited. Herein, we performed a phylogenetic analysis of T. cruzi sequences of the mini-exon intergenic region obtained from a large cohort of pregnant women and newborns from Argentina, Honduras, and Mexico, to assess parasite genetic diversity and possible associations with congenital transmission. Analysis of 105 samples (including five paired samples) from maternal and umbilical cord blood indicated that T. cruzi DTU distribution was similar among pregnant women and newborns from these three countries, with a high frequency of TcII-TcV-TcVI DTUs, including mixed infections with TcI. However, phylogenetic analysis revealed that although the same parasite haplotypes circulated in these three countries, they were present at different frequencies, leading to significant geographic differences. Of importance, a strong association was observed between parasite haplotypes and congenital infection of newborns. Thus, the identification of parasite haplotypes in pregnant women, but not of parasite DTUs, may help predict congenital transmission of T. cruzi.
Asunto(s)
Enfermedad de Chagas/parasitología , Filogenia , Complicaciones Parasitarias del Embarazo/parasitología , Trypanosoma cruzi/genética , Argentina , Enfermedad de Chagas/transmisión , Exones , Femenino , Técnicas de Genotipaje , Haplotipos , Honduras , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , México , Reacción en Cadena de la Polimerasa , EmbarazoRESUMEN
INTRODUCTION: The microscopic examination of microhematocrit tubes (mHCT) has been proposed as the gold standard for acute and congenital Chagas disease diagnosis. We compared different mHCT methodologies detecting T. cruzi parasites in the blood. METHODS: The rotating method, water mount, and immersion oil methods were compared for their suitability, sensitivity, and specificity. RESULTS: The rotating method was easier, faster, and more sensitive than the others with 100% specificity. CONCLUSIONS: The rotating method is feasible for laboratory technicians with standard training in microscopic techniques and is recommended for the diagnosis of acute Chagas disease in primary health care facilities.
Asunto(s)
Tubo Capilar , Centrifugación/métodos , Enfermedad de Chagas/diagnóstico , Hematócrito/métodos , Parasitemia/diagnóstico , Trypanosoma cruzi/aislamiento & purificación , Animales , Enfermedad de Chagas/sangre , Enfermedad de Chagas/parasitología , Servicios de Laboratorio Clínico , Humanos , Parasitemia/parasitología , Sensibilidad y EspecificidadRESUMEN
Abstract INTRODUCTION: The microscopic examination of microhematocrit tubes (mHCT) has been proposed as the gold standard for acute and congenital Chagas disease diagnosis. We compared different mHCT methodologies detecting T. cruzi parasites in the blood. METHODS: The rotating method, water mount, and immersion oil methods were compared for their suitability, sensitivity, and specificity. RESULTS: The rotating method was easier, faster, and more sensitive than the others with 100% specificity. CONCLUSIONS: The rotating method is feasible for laboratory technicians with standard training in microscopic techniques and is recommended for the diagnosis of acute Chagas disease in primary health care facilities.
Asunto(s)
Humanos , Animales , Trypanosoma cruzi/aislamiento & purificación , Centrifugación/métodos , Enfermedad de Chagas/diagnóstico , Parasitemia/diagnóstico , Tubo Capilar , Hematócrito/métodos , Sensibilidad y Especificidad , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/sangre , Parasitemia/parasitología , Servicios de Laboratorio ClínicoRESUMEN
Compared with South America, there is a lack of epidemiologic studies about the risk of congenital transmission of Trypanosoma cruzi in Central America and Mexico. It has been suggested that T. cruzi genotypes might differ by region and that congenital transmission might vary according to the parasite's genotype. Our objective was to compare T. cruzi congenital transmission rates in three countries. We performed an observational prospective study in 2011-2014 enrolling women at delivery in one hospital in Argentina, two hospitals in Honduras, and two hospitals in Mexico. Congenital T. cruzi infection was defined as the presence of one or more of the following criteria: presence of parasites in cord blood (direct parasitological microscopic examination) with positive polymerase chain reaction (PCR) in cord blood, presence of parasites in infant's blood at 4-8 weeks (direct parasitological microscopic examination), and persistence of T. cruzi-specific antibodies at 10 months, as measured by at least two tests. Among 28,145 enrolled women, 347 had at least one antibody rapid test positive in cord blood and a positive enzyme-linked immunosorbent assay in maternal blood. PCR in maternal blood was positive in 73.2% of the cases, and genotyping identified a majority of non-TcI in the three countries. We found no (0.0%; 95% confidence interval [CI]: 0.0, 2.0) confirmed congenital case in Honduras. Congenital transmission was 6.6% (95% CI: 3.1, 12.2) in Argentina and 6.3% (95% CI: 0.8, 20.8) in Mexico. Trypanosoma cruzi non-TcI predominated and risks of congenital transmission were similar in Argentina and Mexico.
Asunto(s)
Enfermedad de Chagas/transmisión , Transmisión de Enfermedad Infecciosa/estadística & datos numéricos , Adulto , Enfermedad de Chagas/epidemiología , Femenino , Sangre Fetal/parasitología , Honduras/epidemiología , Humanos , Recién Nacido , México/epidemiología , Embarazo , Estudios Prospectivos , Estadísticas no Paramétricas , Trypanosoma cruzi/patogenicidadRESUMEN
Congenital infection with Trypanosoma cruzi is a global problem, occurring on average in 5% of children born from chronically infected mothers in endemic areas, with variations depending on the region. This presentation aims to focus on and update epidemiological data, research methods, involved factors, control strategy and possible prevention of congenital infection with T. cruzi. Considering that etiological treatment of the child is always effective if performed before one year of age, the diagnosis of infection in pregnant women and their newborns has to become the standard of care and integrated into the surveillance programs of syphilis and human immunodeficiency virus. In addition to the standard tests, polymerase chain reaction performed on blood of neonates of infected mothers one month after birth might improve the diagnosis of congenital infection. Recent data bring out that its transmission can be prevented through treatment of infected women before they become pregnant. The role of parasite genotypes and host genetic factors in parasite transmission and development of infection in foetuses/neonates has to be more investigated in order to better estimate the risk factors and impact on health of congenital infection with T. cruzi.
Asunto(s)
Humanos , Femenino , Embarazo , Recién Nacido , Enfermedad de Chagas/congénito , Transmisión Vertical de Enfermedad Infecciosa , Complicaciones Parasitarias del Embarazo , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/prevención & control , Genotipo , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Complicaciones Parasitarias del Embarazo/epidemiología , Complicaciones Parasitarias del Embarazo/prevención & control , Factores de Riesgo , Trypanosoma cruziRESUMEN
Congenital infection with Trypanosoma cruzi is a global problem, occurring on average in 5% of children born from chronically infected mothers in endemic areas, with variations depending on the region. This presentation aims to focus on and update epidemiological data, research methods, involved factors, control strategy and possible prevention of congenital infection with T. cruzi. Considering that etiological treatment of the child is always effective if performed before one year of age, the diagnosis of infection in pregnant women and their newborns has to become the standard of care and integrated into the surveillance programs of syphilis and human immunodeficiency virus. In addition to the standard tests, polymerase chain reaction performed on blood of neonates of infected mothers one month after birth might improve the diagnosis of congenital infection. Recent data bring out that its transmission can be prevented through treatment of infected women before they become pregnant. The role of parasite genotypes and host genetic factors in parasite transmission and development of infection in foetuses/neonates has to be more investigated in order to better estimate the risk factors and impact on health of congenital infection with T. cruzi.
Asunto(s)
Enfermedad de Chagas/congénito , Transmisión Vertical de Enfermedad Infecciosa , Complicaciones Parasitarias del Embarazo , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/prevención & control , Femenino , Genotipo , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Embarazo , Complicaciones Parasitarias del Embarazo/epidemiología , Complicaciones Parasitarias del Embarazo/prevención & control , Factores de Riesgo , Trypanosoma cruziRESUMEN
BACKGROUND: Trypanosoma cruzi has been divided into Discrete Typing Units I and non-I (II-VI). T. cruzi I is predominant in Mexico and Central America, while non-I is predominant in most of South America, including Argentina. Little is known about congenital transmission of T. cruzi I. The specific aim of this study is to determine the rate of congenital transmission of T. cruzi I compared to non-I. METHODS/DESIGN: We are conducting a prospective study to enroll at delivery, 10,000 women in Argentina, 7,500 women in Honduras, and 13,000 women in Mexico. We are measuring transmitted maternal T. cruzi antibodies by performing two rapid tests in cord blood (Stat-Pak, Chembio, Medford, New York, and Trypanosoma Detect, InBios, Seattle, Washington). If at least one of the results is positive, we are identifying infants who are congenitally infected by performing parasitological examinations on cord blood and at 4-8 weeks, and serological follow-up at 10 months. Serological confirmation by ELISA (Wiener, Rosario, Argentina) is performed in cord and maternal blood, and at 10 months. We also are performing T. cruzi standard PCR, real-time quantitative PCR and genotyping on maternal venous blood and on cord blood, and serological examinations on siblings. Data are managed by a Data Center in Montevideo, Uruguay. Data are entered online at the sites in an OpenClinica data management system, and digital pictures of data forms are sent to the Data Center for quality control. Weekly reports allow for rapid feedback to the sites.
Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Enfermedad de Chagas/transmisión , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Trypanosoma cruzi/inmunología , Adulto , Argentina , Enfermedad de Chagas/congénito , Enfermedad de Chagas/diagnóstico , Enfermedad de Chagas/prevención & control , Femenino , Sangre Fetal/inmunología , Honduras , Humanos , Lactante , Recién Nacido , México , Embarazo , Complicaciones Parasitarias del Embarazo/sangre , Complicaciones Parasitarias del Embarazo/diagnóstico , Estudios Prospectivos , Trypanosoma cruzi/genéticaRESUMEN
BACKGROUND: This study investigated the prevalence of Chagas disease (ChD) in pregnant women in Choapa Province (IV Region, Chile) and the vertical transmission of Trypanosoma cruzi. METHOD: ELISA and IFI IgG for ChD was performed for the pregnant women. PCR for T. cruzi was done for all chagasic mothers and their newborns. The congenital infection was confirmed by serial positive PCR and/or ELISA or IFI IgG after age of nine months. The placentas of mothers, with and without ChD, were submitted for histopathology and immunohistochemical study. RESULTS: From 4831 deliveries in 2005-2009 with a serological coverage of 88.6%, it was established that 147 cases (3.4%) had ChD. More than 80% of the pregnancies had a physiological evolution and 90% of the newborn were term. Congenital transmission was demonstrated in six children (4.7%) of the 127 newborn studied by serial PCR (at birth and/or between 3-18 months) and/or ELISA or IIF IgG after age nine months. Most of congenital cases were asymptomatic (67%). The histopathology shows edema, necrosis, fibrinoid deposit in the placentas of 28 of 29 chagasic mothers. In three cases the immnunochemistry demonstrated a decrease in actin expression in trophoblast cells. In one congenital case amastigote nests was observed. CONCLUSIONS: These results indicate that T. cruzi infection in pregnant women and vertical transmission in Chile are still prevalent. For this reason it is important to propose control measures in endemic areas of the country.
Asunto(s)
Enfermedad de Chagas/congénito , Trypanosoma cruzi/aislamiento & purificación , Adolescente , Adulto , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/transmisión , Chile/epidemiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Placenta/parasitología , Reacción en Cadena de la Polimerasa , Embarazo , Complicaciones Parasitarias del Embarazo/parasitología , Prevalencia , Adulto JovenRESUMEN
The objective of this study was to determine the presence of Trypanosoma cruzi in blood samples of mothers with chronic Chagas disease and their newborn by conventional PCR targeted to minicircle kinetoplastidic DNA (kDNA), and to determine the lineages in mother/newborn pairs of the congenital cases by hybridization assays with probes belonging to the TcII, TcI and TcV Discrete Typing Units (DTU). In 63 (57.2%) of the mothers the presence of circulating T. cruzi was demonstrated by PCR immediately before delivery and in three newborn (3%) congenital transmission was confirmed by serial PCR and conventional serology between 1 and 16 months of life, at which point treatment was started. The hybridization signals showed that two of the newborn had the same DTU as their mother (TcI, TcII and TcV), whilst in the third congenital case only TcV was detected in the cord blood, suggesting that in this infant TcI and TcII did not cross the placenta or the parasite was not present at a detectable level. Levels T. cruzi DNA was determined by TaqMan Probe based Real Time PCR assay targeted to nuclear satellite sequences in these three pairs of samples.
Asunto(s)
Enfermedad de Chagas/congénito , Enfermedad de Chagas/epidemiología , Complicaciones Parasitarias del Embarazo/epidemiología , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/aislamiento & purificación , Adolescente , Adulto , Sangre/parasitología , Enfermedad de Chagas/transmisión , Análisis por Conglomerados , ADN de Cinetoplasto/genética , ADN Protozoario/genética , Femenino , Genotipo , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Persona de Mediana Edad , Epidemiología Molecular , Hibridación de Ácido Nucleico , Reacción en Cadena de la Polimerasa , Embarazo , Trypanosoma cruzi/genética , Adulto JovenRESUMEN
The first case of neonatal Chagas was reported in Mexico in 1998, but there have been no studies since then. Therefore, we investigated the rates of congenital infection of Trypanosoma cruzi by examining the seroprevalence among 1448 pregnant women in Oaxaca, Jalisco and Mexico City. We performed ELISAs to screen for recombinant and total antigens in mothers, and examined the frequency of congenital T. cruzi transmission by PCR with cord blood and antibody testing in children when they reached two years old. Our results showed that the prevalence of infection in pregnant women was 7.32% (106/1448) overall, and 4.4% (35/794) in Oaxaca, 12.02% (67/557) in Jalisco and 4.12% (4/97) in the Mexico City. In Oaxaca, T. cruzi infection was detected by PCR in 20% (7/35) of infants born to seroreactive mothers and 11.9% (8/67) in Jalisco. No infections were identified in infants from the Mexico City. From these only eleven serological follow up their children are agree to take blood. Therefore, the maternal-fetal overall transmission rate was 4.08% (4/98) in Oaxaca and 9.1% (3/33) in Jalisco 1.5% (1/65) children with positive serology were given specific treatment Chagas. In conclusion, these are the first reports of the rates of congenital Chagas disease in Mexico. The seroprevalence was higher in mothers from Jalisco, and could be related to that there is not the periodic fumigation of the transmitting vector performed in that state. The high rates of maternal-fetal transmission found in Oaxaca could be related to the differences of pathogenicity of trypanosome. No association between both the rate of congenital transmission and the gynecologic anthropometric data was observed.
Asunto(s)
Enfermedad de Chagas/congénito , Enfermedad de Chagas/transmisión , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Complicaciones Parasitarias del Embarazo/epidemiología , Trypanosoma cruzi/inmunología , Adolescente , Adulto , Anticuerpos Antiprotozoarios/sangre , Enfermedad de Chagas/epidemiología , Preescolar , Estudios de Cohortes , ADN Protozoario/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Sangre Fetal/parasitología , Humanos , Lactante , Recién Nacido , México/epidemiología , Reacción en Cadena de la Polimerasa , Embarazo , Estudios Seroepidemiológicos , Encuestas y Cuestionarios , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Adulto JovenRESUMEN
Congenital Chagas disease acquired special importance in Chile after the certification of the control of Triatoma infestans and transmission by blood donors affected with Trypanosoma cruzi. In order to establish adequate protocols for intervention and control in infected mother-neonate pairs in endemic zones of Chagas disease, we present partial results (2005-2008) of a pilot project which is being carried out in the Province of Choapa, IV Region, Chile, whose objectives are: determine the current prevalence of the disease in pregnant women, estimate the incidence of vertical transmission of T. cruzi to newborns, determine the lineages of the parasite present in mothers who do and do not transmit the disease, determine the prevalence of Chagas disease in maternal grandmothers of neonates and study placental histopathology. Preliminary results indicated that in this study period, 3.7% of the women who gave birth in the Province have Chagas disease and 2.5% of their newborns were infected. The most frequent T. cruzi genotypes found in mothers studied during pregnancy were TCI and TCIId, either alone or in mixed infections. A high percentage (74.3%) of the grandmothers studied was infected with the parasite. In 29 placentas from mothers with Chagas disease we observed edema, necrosis, fibrinoid deposits and slight lymphoplasmocyte infiltration. In three placentas we found erythroblastosis and in one of them amastigote forms of T. cruzi; this was one of the cases of congenital infection. The evaluation of the diagnostic and control protocols generated will allow us to determine if it has been possible to modify the natural history of vertical transmission of T. cruzi in Chile.
Asunto(s)
Enfermedad de Chagas/transmisión , Enfermedades Endémicas , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Trypanosoma cruzi/genética , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Chagas/congénito , Enfermedad de Chagas/epidemiología , Chile/epidemiología , Femenino , Genotipo , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Persona de Mediana Edad , Placenta/parasitología , Placenta/patología , Embarazo , PrevalenciaRESUMEN
Congenital Chagas disease acquired special importance in Chile after the certification of the control of Triatoma infestans and transmission by blood donors affected with Trypanosoma cruzi. In order to establish adequate protocols for intervention and control in infected mother-neonate pairs in endemic zones of Chagas disease, we present partial results (2005-2008) of a pilot project which is being carried out in the Province of Choapa, IV Region, Chile, whose objectives are: determine the current prevalence of the disease in pregnant women, estimate the incidence of vertical transmission of T. cruzi to newborns, determine the lineages of the parasite present in mothers who do and do not transmit the disease, determine the prevalence of Chagas disease in maternal grandmothers of neonates and study placental histopathology. Preliminary results indicated that in this study period, 3.7 percent of the women who gave birth in the Province have Chagas disease and 2.5 percent of their newborns were infected. The most frequent T. cruzi genotypes found in mothers studied during pregnancy were TCI and TCIId, either alone or in mixed infections. A high percentage (74.3 percent) of the grandmothers studied was infected with the parasite. In 29 placentas from mothers with Chagas disease we observed edema, necrosis, fibrinoid deposits and slight lymphoplasmocyte infiltration. In three placentas we found erythroblastosis and in one of them amastigote forms of T. cruzi; this was one of the cases of congenital infection. The evaluation of the diagnostic and control protocols generated will allow us to determine if it has been possible to modify the natural history of vertical transmission of T. cruzi in Chile.
Asunto(s)
Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Recién Nacido , Persona de Mediana Edad , Embarazo , Enfermedad de Chagas/transmisión , Enfermedades Endémicas , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Trypanosoma cruzi/genética , Enfermedad de Chagas/congénito , Enfermedad de Chagas/epidemiología , Chile/epidemiología , Genotipo , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Prevalencia , Placenta/parasitología , Placenta/patologíaRESUMEN
Chagas disease (CD) is endemic to Latin America; its prevalence is highest in Bolivia. CD is sometimes seen in the United States and Canada among migrants from Latin America, whereas it is rare in Europe. We report 9 cases of imported CD in France from 2004 to 2006.
Asunto(s)
Enfermedad de Chagas/diagnóstico , Enfermedad de Chagas/epidemiología , Adulto , Animales , Enfermedad de Chagas/complicaciones , Enfermedad de Chagas/tratamiento farmacológico , Femenino , Francia/epidemiología , Guyana Francesa/etnología , Humanos , Masculino , Persona de Mediana Edad , Nitroimidazoles/uso terapéutico , Tripanocidas/uso terapéutico , Trypanosoma cruzi/aislamiento & purificaciónRESUMEN
To better understand the factors involved in maternal-fetal transmission of Trypanosoma cruzi, we compared DNA levels-obtained by use of quantitative real-time PCR and parasitic genotypes determined by PCR amplification followed by hybridization-in Bolivian mothers and their congenitally infected newborns. Mothers and their neonates displayed markedly different parasitic DNA levels, as most maternal estimated parasitemias (> 90%) were < 10 parasites/mL, whereas those of 76% of their newborns were > 1,000 parasites/mL. Comparison of T. cruzi TcII sublineages infecting mothers and newborns showed identity, without evidence of mixed infection in mothers or neonates. Analysis of minor variants of TcIId-genotyped parasites using sequence class probes hybridizing with hypervariable domains of kDNA minicircles showed discrepancies in half of mother/newborn pairs.
Asunto(s)
Enfermedad de Chagas/transmisión , ADN Protozoario/análisis , Transmisión Vertical de Enfermedad Infecciosa , Complicaciones Infecciosas del Embarazo/parasitología , Trypanosoma cruzi/genética , Animales , Bolivia , Enfermedad de Chagas/sangre , Enfermedad de Chagas/congénito , Enfermedad de Chagas/parasitología , Femenino , Humanos , Recién Nacido , Reacción en Cadena de la Polimerasa , Embarazo , Complicaciones Infecciosas del Embarazo/sangre , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/aislamiento & purificaciónRESUMEN
This study aims to typify the Trypanosoma cruzi (sub)lineage(s) in umbilical cord blood of congenitally infected Bolivian newborns, using PCR amplifications of "Region Markers", mini-exon or kDNA fragments followed by hybridization or sequencing. New probes were also designed to distinguish three variants within the TcIId sublineage. The IIb, IId, or IIe T. cruzi sublineages, as well as different variants of the IId sublineage, were detected in infected neonates, whereas mixed infections were not found. The frequencies of the IId sublineage were similar in neonates (95.1%) and adults of the same area (94.1%). The IId-infected newborns displayed either asymptomatic, or severe and fatal clinical forms of congenital Chagas disease, as well as low or high parasitemia. Altogether these data show that T. cruzi DNA polymorphism, based on the presently available markers, is not associated with the occurrence of congenital infection or the development of severe clinical forms of congenital Chagas disease.
Asunto(s)
Enfermedad de Chagas/parasitología , Polimorfismo Genético , Trypanosoma cruzi/genética , Animales , Bolivia/epidemiología , Enfermedad de Chagas/congénito , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/mortalidad , ADN Protozoario/análisis , Sangre Fetal , Humanos , Transmisión Vertical de Enfermedad Infecciosa , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/aislamiento & purificaciónRESUMEN
BACKGROUND: Comparing two surveys performed in Bolivia in 1992-1994 and 1999-2001, we reported a significant decrease in the proportions of severe and mortal forms of congenital Chagas disease. This might be due to a reduction of vectorial density (VD) in maternal residence area, raising the question of a possible causal relationship between such VD, maternal parasitaemia and prognosis of congenital infection with Trypanosoma cruzi. METHOD: Comparisons of haematological and parasitological data obtained from Bolivian mothers infected with T. cruzi, and of clinical and biological data obtained from their infected and uninfected newborns, stratified according to VD in the area of maternal residence. RESULTS: i) Blood hematocrit rates or hemoglobin amounts were within the normal ranges and similar in all the maternal groups, whatever the VD in their areas of residence; ii) mothers living in high VD areas displayed a higher frequency of hemocultures positive for T. cruzi; iii) newborns congenitally infected with T. cruzi, but not uninfected babies born from infected mothers, displayed higher frequencies of very low Apgar scores, low birth weights, prematurity, respiratory distress syndrome or anasarca, as well as higher mortality rates when their mothers lived in areas of high VD. CONCLUSION: Frequent bites of blood sucking Reduvidae during pregnancy do not induce maternal anaemia, but, likely through multiple maternal re-infections with T. cruzi, increase maternal parasitemia and worsen congenital Chagas disease. Maternal dwelling in areas of high VD is associated with a serious increased risk of severe and mortal congenital Chagas disease.
Asunto(s)
Enfermedad de Chagas/congénito , Madres , Animales , Puntaje de Apgar , Bolivia/epidemiología , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/mortalidad , Vectores de Enfermedades , Enfermedades Endémicas , Femenino , Edad Gestacional , Hematócrito , Hemoglobinas/análisis , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Morbilidad , Densidad de Población , Embarazo , Características de la Residencia , Trypanosoma cruziRESUMEN
In Bolivia, the prevalence of infection by T. cruzi in women in fertile age can vary between 20 and 60%. The present study made in the Maternity Germin Urquidi of Cochabamba - Bolivia, it has demonstrated, that 19.9% of the mothers who go to this hospitable center to be taken care of in the childbirth, they are carrying of the infection and that 4,6% of them, they are going to transmit, by transplacentaria route, the infection to its babies. Of the 71 children born with congenital Chagas, only 47,8 % present/display some type of alteration or of development(Apgar to 1 minute low, BPN, prematuridad, pathological dismadurez) or signs (SDR, hepatomegalia, esplenomegalia, neurological signs, cardiomegalia, anasarca, petequias). When investigating the effect of the differences in the vectorial density (low, medium and high) of the zone of maternal residence, on the transmission of the infection of the mother infected to the fetus, we concluded that the rate of transmission of the congenital infection of T. cruzi is not modified by the level of endemicidad of the zone of maternal residence. By another infected new born sides whose mothers reside in zones of high endemicidad present/display, most frequently and of significant way, Apgar to 1 minute < to 7, low weight when being born and prematuridad or an association of these alterations with respiratory syndrome of distress or anasarca, when one compares them with new born of resident mothers in the zones of loss or medium endemicidad, mortality in this group is greater. These results suggest calls to account it of the mothers, in areas of high endemicidad, she is associate with a serious increase in the risk of Disease of newborn severe and mortal congenital Chagas in.
Asunto(s)
Enfermedad de Chagas/congénito , Enfermedades Endémicas , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Insectos Vectores/fisiología , Complicaciones Parasitarias del Embarazo , Adulto , Animales , Puntaje de Apgar , Bolivia/epidemiología , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/transmisión , Demografía , Factores Epidemiológicos , Femenino , Humanos , Recién Nacido , Masculino , Densidad de Población , Embarazo , Prevalencia , Trypanosoma cruzi/fisiologíaRESUMEN
The aim of this study was to validate the method of microhematocrit tube, as a rapid method to estimate the parasitemia in blood and to associate the parasites concentration with the morbidity and mortality of new born children with congenital Chagas diseases. Our results were determined experimentally and shown that the detection limit of the microhematocrit tube method is 40 parasites/ml when at least one of the four observed tubes is positive. Besides, it was also established that when the four examined tubes are positive the parasitemia in blood reaches more than 100 parasites/ml. It is important to highlight the modification made by our laboratory in the microscopic observation of the microhematocrit tubes with respect to the methodology used by previous investigators. A positive association exists between a high number of parasites in blood and the morbi-mortality of the newly born children with congenital chagas. The results of positive association between the parasitic load and the morbility and mortality could constitute an argument to understand the possible role of the parasite in the pathology of the disease.