Revisión sistemática de la exactitud diagnóstica de la gota gruesa en comparación con la reacción en cadena de la polimerasa para malaria asociada al embarazo, 2010-2022 / Systematic review of the diagnostic accuracy of thick smear compared to polymerase chain reaction for pregnancy-associated malaria, 2010-2022

RESUMEN Objetivos. Evaluar la exactitud de gota gruesa (GG) frente a la reacción en cadena de la polimerasa (PCR) cuantitativa para la malaria asociada al embarazo (MAE). Materiales y métodos. Se realizó una revisión sistemática de pruebas diagnósticas en nueve bases de datos. Se evaluó la calidad metodológica con QUADAS. Se estimó sensibilidad, especificidad, cociente de probabilidad positivo (CPP) y negativo (CPN), razón de odds diagnóstica (ORD) y área bajo la curva ROC. Se determinó la heterogeneidad con el estadístico Q de Der Simonian-Laird y la incertidumbre con el porcentaje de peso de cada estudio sobre el resultado global. Resultados. Se incluyeron diez estudios con 5691 gestantes, 1415 placentas y 84 neonatos. En los estudios con nPCR (PCR anidada) y qPCR (PCR cuantitativa) como estándar, los resultados de exactitud diagnóstica fueron estadísticamente similares, con sensibilidad muy baja (50 y 54%, respectivamente), alta especificidad (99% en ambos casos), alto CPP y deficiente CPN. Usando nPCR la OR diagnóstica fue 162 (IC95%=66-401) y el área bajo la curva ROC fue 95%, mientras que con qPCR fueron 231 (IC95%=27-1951) y 78%, respectivamente. Conclusiones. Mediante un protocolo exhaustivo se demostró el bajo desarrollo de investigaciones sobre la exactitud diagnóstica de la GG en MAE. Se demostró que la microscopía tiene un desempeño deficiente para el diagnóstico de infecciones asintomáticas o de baja parasitemia, lo que afianza la importancia de implementar otro tipo de técnicas en el seguimiento y control de las infecciones por malaria en las gestantes, con el fin de lograr el control y posible eliminación de la MAE.

ABSTRACT Objective. To evaluate the accuracy of thick smear (TS) versus quantitative polymerase chain reaction (PCR) for pregnancy-associated malaria (PAM). Materials and methods. We carried out a systematic review of diagnostic tests in nine databases. Methodological quality was evaluated with QUADAS. Sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and area under the ROC curve were estimated. Heterogeneity was determined with the Der Simonian-Laird Q method and uncertainty with the weighted percentage of each study on the overall result. Results. We included 10 studies with 5691 pregnant women, 1415 placentas and 84 neonates. In the studies with nested PCR (nPCR) and quantitative PCR (qPCR) as the standard, the diagnostic accuracy results were statistically similar, with very low sensitivity (50 and 54%, respectively), high specificity (99% in both cases), high PLR and poor NLR. When nPCR was used, the DOR was 162 (95%CI=66-401) and the area under the ROC curve was 95%, while with qPCR it was 231 (95%CI=27-1951) and 78%, respectively. Conclusions. We demonstrated that research on the diagnostic accuracy of TS in PAM is limited. Microscopy showed poor performance in the diagnosis of asymptomatic or low parasitemia infections, which reinforces the importance of implementing other types of techniques for the follow-up and control of malaria infections in pregnant women, in order to achieve the control and possible elimination of PAM.

Seroprevalence of toxoplasmosis in pregnant women and its associated factors among hospital and community populations in Lambayeque, Peru

Abstract INTRODUCTION Toxoplasmosis is a zoonosis caused by Toxoplasma gondii. This study investigated the prevalence and factors associated with toxoplasmosis among pregnant women. METHODS We followed an analytical observational study. From July 2016 to June 2017, 218 pregnant women were selected. The infection was detected through serological dosage of anti-T.gondii Immunoglobulin(Ig) M and IgG antibodies. RESULTS The seroprevalence was 35.8%; the factors associated with infection were consumption of non-drinking water, residence in an urban area, and threatened abortion during the current pregnancy. CONCLUSIONS The seroprevalence of toxoplasmosis among pregnant women is high. The risk factors are dependent on environmental determinants.

Diagnóstico y manejo de la restricción del crecimiento intrauterino en fetos de gestantes provenientes de zonas endémicas para la malaria / Diagnosis and management of intrauterine growth restriction in fetuses of pregnant women from endemic areas for malaria

RESUMEN Introducción: La malaria es una enfermedad infecciosa tropical de gran impacto epidemiológico a nivel mundial; las poblaciones con mayor susceptibilidad de padecerla son los niños menores de 5 años y las gestantes, en quienes, se pude no solo comprometer la salud de la madre sino también la del producto y su desarrollo, pudiendo ocurrir diferentes desenlaces adversos entre ellos la restricción del crecimiento intrauterino (RCIU), incrementando sustancialmente las tasas de mortalidad materna y perinatal. Es importante establecer un diagnóstico preciso y oportuno de la RCIU en fetos de gestantes que padecen de malaria, con el fin de llevar a cabo un enfoque de seguimiento y de manejo que puedan disminuir las complicaciones asociadas a la enfermedad. Métodos: Se realizó una búsqueda bibliográfica en la base de datos de Cochrane y PubMed, libros de la especialidad y consensos de sociedades científicas, relativos a los términos de: malaria during pregnancy, intrauterine growth restriction y malaria and fetal growth restriction. Se seleccionaron finalmente 42 artículos para análisis completo y crítico, que justificara la elaboración de esta revisión. Conclusión: esta revisión aporta elementos para establecer un alto grado de sospecha diagnóstica de malaria durante el embarazo en zonas endémicas para la malaria; además revela la necesidad de implementar protocolos de manejo especifico ante la RCIU según sea la etiología; ya que estas medidas impactaran positivamente en los resultados adversos de la enfermedad, sin olvidar que lo primordial es proteger plenamente a las mujeres contra la malaria desde el comienzo del embarazo hasta el parto.

Toxoplasmosis congénita: Diagnóstico serológico, RPC, aislamiento y caracterización molecular de Toxoplasma gondii / Congenital toxoplasmosis: Serology, PCR, parasite isolation and molecular characterization of Toxoplasma gondii

Resumen Introducción El diagnóstico de toxoplasmosis congénita (TC) en el recién nacido es muy importante porque debe recibir tratamiento siempre, sintomático o no, para evitar o aminorar las secuelas de la enfermedad. Objetivo Evaluación comparativa de los métodos disponibles en la institución para el diagnóstico de TC. Materiales y Métodos Se evaluaron métodos diagnósticos en 67 niños cuyas madres cursaron toxoplasmosis aguda durante el embarazo. Se utilizó la técnica de Sabin Feldman para IgG al nacimiento y durante el seguimiento serológico hasta el año de vida. Para determinar IgM, IgA e IgE se utilizó la técnica immunosorbent agglutination assay (ISAGA). El diagnóstico directo se realizó por reacción de polimerasa en cadena (RPC), aislamiento y caracterización molecular del parásito. Resultados La sensibilidad (S) de ISAGA IgM fue 87%, ISAGA IgA 91% y la especificidad (E) fue 100% para ambas; cuando se realizaron en conjunto, la S aumentó a 98%. La detección de IgE contribuyó al diagnóstico cuando se la detectó sólo en la sangre del neonato y no en sangre materna. Se aisló el parásito en cuatro casos de TC, uno fue genotipo II y los otros tres, genotipos "atípicos". La S del aislamiento fue 80% y la E 100%. Conclusión Los métodos serológicos utilizados mostraron una buena eficacia diagnóstica. Un caso fue detectado sólo por el aislamiento y la caracterización molecular tiene gran valor epidemiológico.

Background. Congenital toxoplasmosis diagnosis in the newborn is a very important issue due to the need for early treatment to prevent future sequels. Aim To compare available methods at the institution for the diagnosis of congenital toxoplasmosis. Material and Methods In this study we have evaluated the different diagnostic tests used in 67 congenital exposed newborns, including serological tests, PCR, parasite isolation and molecular characterization. Results The ISAGA IgM and IgA tests showed sensitivity (Se) of 87 and 91%, respectively, and specificity (Sp) of 100%. When ISAGA IgM and IgA were performed simultaneously, the Se increased to 98% and the Sp was 100%. The presence of IgE contributed to the diagnosis when it was detected in the child's serum but not in maternal blood. In four congenital infected children the parasite was isolated and genotyped: one was genotype II and the other three were "atypical" genotypes. No parasite was isolated in children without congenital toxoplasmosis. Discussion Overall, serological tests showed a good diagnostic performance although in one case they were all negative and isolation was the only tool to identify the infection. We conclude that it is essential to use all diagnostic tests in every single exposed child, including if possible, molecular characterization due to its epidemiological implication.

A cross sectional study of leptospirosis and fetal death in Yucatan, Mexico / Estudio transversal de leptospirosis y muerte fetal en Yucatán, México

Introduction: Leptospirosis is a zoonotic disease affecting mainly to low income human population. Acute leptospiral infection during pregnancy has been associated with spontaneous abortion and fetal death during the first trimester and the abortion may occur as consequence of systemic failure. Objective: To estimate the frequency of Leptospira interrogans infection in women with spontaneous abortion in the state of Yucatan, Mexico. Methods: A cross sectional study on women with spontaneous abortion was conducted. Serum samples were tested for Leptospirosis by the microaglutination test, to estimate the frequency of the infecting serovar. The indirect ELISA IgM was used to detect recent infection by L. interrogans. DNA was extracted from paraffin-embedded tissue of placenta for PCR detection of L. interrogans. Results: Overall frequency of infection with L. interrogans in the 81 women with abortion was 13.6%. Five of the 12 serovars evaluated were found and included. Two of the 11 women with abortion and positive to microaglutination test were also positive to the ELISA IgM test. None samples were positive for PCR Leptospira diagnosis. Conclusion: two women could be associated with spontaneous abortion due to leptospirosis, because they showed antibodies against L. interrogans in the microaglutination test and ELISA IgM assays. Differences between regions were found with respect to the prevalences of lesptospirosis.

Introducción: Leptospirosis es una enfermedad zoonótica que afecta principalmente la población humana de bajos recursos. Infección aguda por leptospirosis durante el embarazo se ha asociado con aborto espontáneo y muerte fetal durante el primer trimestre del embarazo. Objetivo: Estimar la frecuencia de infección por Leptospira interrogans en mujeres con aborto espontáneo en el estado de Yucatán, México. Métodos: Se efectuó un estudio trasversal en 81 mujeres con aborto espontáneo. La prueba de referencia para Leptospirosis, prueba de microaglutinación, se utilizó para estimar la frecuencia de la serovar infectante. El ELISA IgM indirecto se utilizó para detectar infección reciente por L. interrogans. Se extrajo ADN a partir de tejido embebido en parafina de placenta para la detección de L. interrogans por PCR. Resultados: La frecuencia global de la infección con L. interrogans en 81 mujeres con aborto, fue del 13.6%. Se encontró cinco de 12 serovares de Leptospira. Dos de las 11 mujeres con aborto espontáneo y positivo a microaglutinación también fueron positivas a la prueba ELISA IgM. Ninguna muestra fue positiva hacia el diagnóstico PCR de Leptospira. Conclusion: Dos mujeres podrían estar asociados con el aborto espontáneo debido a la leptospirosis, porque mostraron anticuerpos contra L. interrogans en la microaglutinación y ensayos de ELISA IgM. Diferencias entre regiones fueron encontradas con respecto a las prevalencias de leptospirosis.

Congenitally transmitted visceral leishmaniasis: report of two brazilian human cases

Visceral leishmaniasis is a relevant public health problem worldwide. Most of the reported cases in Latin America are from Brazil. Herein we report two human cases of congenitally transmitted visceral leishmaniasis in two patients who developed symptoms during pregnancy. The diagnosis was made by visual examination of Leishmania parasites in bone marrow aspirates of the mothers and by detecting parasite kDNA in bone marrow samples of the newborn children using polymerase chain reaction.

Incidence of Trypanosoma cruzi transmission through breastfeeding during acute experimental Chagas disease

OBJECTIVE: To verify the incidence of T. cruzi transmission through breastfeeding during acute experimental Chagas' disease. METHODS: Fifteen female Swiss mice were mated and, after pregnancy confirmation, placed in individual cages. A few hours after birth, the females were inoculated with 0.1 mL of blood containing approximately 3 x 10(5) trypomastigote forms of Y strain of T. cruzi and continued breastfeeding for 25 days. RESULTS: In 142 offspring examined no infection through breast-feeding was observed. CONCLUSIONS: The low number of trypomastigote forms ingested by the newborn mice combined with biological and biochemical characteristics of blood trypomastigotes may explain the lack of transmission in this experiment.

Congenital toxoplasmosis transmitted by human immunodeficiency-virus infected women

We report the occurrence of congenital toxoplasmosis in three infants born to HIV infected women who had high anti-toxoplasma IgG and negative IgM during pregnancy. We briefly reviewed available literature and discussed the possible transmission mechanisms of congenital toxoplasmosis among HIV infected pregnant women. Serum samples were tested for Toxoplasma gondii IgM and IgG antibodies using commercial enzyme immunoassay and IgG-avidity tests. In the first case, fetal death occurred at 28th week of gestation. In the second case, congenital toxoplasmosis was diagnosis at 6th month of life; and in the third case, an HIV-infected newborn, congenital toxoplasmosis was asymptomatic. These cases point out to the possibility of enhanced maternal-fetal transmission of T. gondii infection by HIV-infected women chronically infected, which may have important public health consequences, considering that increasing frequency of HIV-infection has been observed among women of childbearing age around the world.

Infection and invasion mechanisms of Trypanosoma cruzi in the congenital transmission of Chagas' disease: A proposal

Chagas' disease is produced by the haemophlagelated protozoan Trypanosoma cruzi and transmitted by haematophages insects such as Triatoma infestans (vinchuca). Due to vector control, congenital transmission gains importance and is responsible for the presence and expansion of this disease in non-endemic areas. The mechanisms of congenital infection are uncertain. It has been suggested that the parasite reaches the fetus through the bloodstream by crossing the placental barrier, and that congenital Chagas' disease is the result of complex interactions between the immune response, placental factors, and the parasite's characteristics. We review the cellular and molecular mechanisms of infection and invasion of the parasite and how immune and placental factors may modulate this process. Finally, we propose a possible model for the vertical transmission of Chagas' disease.

Anomalías morfológicas y estructurales en fetos de ratones con infección aguda experimental por Trypanosoma cruzi / Morphological and structural anomalies in fetuses of mice with acute experimental infection by Trypanosoma cruzi

El presente estudio muestra el desarrollo de fetos de ratones hembras NMRI inoculadas con la cepa M/HOM/BRA/53/Y de trypanosoma cruzi y preñadas durante la fase aguda de la infección. Altos niveles de parasitemias fueron observados en las ratones con 30 días post-infección y 20 días de gestación, en comparación con las detectadas en los ratones vírgenes e infectadas con T. cruzi. En 3 de los fetos (15%) provenientes de dos madres infectadas/gestantes con altas parasitemias, se observaron signos de anomalías congénitas morfológicas y estructurales músculo-esqueléticas. Presentándose en uno de los fetos la formación de dos protuberancias, una sobre el lado dorsal del cuerpo y la otra en la base de la pata inferior izquierda, en otro de los fetos, la pata derecha se desarrolló sobre el lado derecho de la cara y en un tercer feto se formó una protuberancia en la pata anterior izquierda a nivel de la región subescapular. El estudio histopatológico con hematoxilina y eosina de los tejidos muscular esquelético y cardíaco, mostró en el 10% (2/20) de los tejidos fetales, intenso infiltrado celular mononuclear con predominio de linfocitos, macrófagos o histiocitos y monocitos entre las fibras musculares y cardíacas, con discreta miositis y miocarditis. Con la técnica de peroxidada anti peroxidada se observaron abundantes depósitos antigénicos, tanto en placenta como en músculo esquelético de los fetos con alteraciones morfológicas. En los ratones infectadas/gestantes los fetos presentaron reducción del peso corporal y retardo en el crecimiento fetal, así como reducción en el número de fetos de 10 en comparación con 14 fetos de mayor tamaño y aspecto normal desarrollados en las ratonas sanas preñadas.

The present study shows the development of the fetuses from pregnant female mice NMRI inoculated with M/HOM/BRA/53/Y Trypanosoma cruzi strain. The infection revealed the highest levels of patent parasitemia in mice with 30 days postinfection and 20 days of pregnancy in comparison with infected unmated mice. Three fetuses (15%) from two infected mice with high levels of parasitemia, showed morphological and structural muscularskeletal congenital anomalies. Two protuberances were observed, one on the dorsal side of the body, and the other on the left footpad base. In another fetus his right footpad came out from the right part of his face and in the 3rd one it was observed a lump in the left leg, above the level subscapular region. The histophatological study with hematoxilin-eosin staining of skeletal muscle and cardiac tissue, showed in 10% (2/20) of the mice, inflammatory infiltrate with lymphocytes, macrophages and monocytes into muscular and cardiac fibers, with discrete myositis and myocarditis. Peroxidase anti-peroxidase staining showed T. cruzi antigens in placenta and skeletal muscle of the fetuses with morphological alterations. In the pregnant mice, fetuses also showed both, loss of weight and growth retardation, as well as reduction of the number of fetuses to 10 in comparison with 14 fetuses in normal and healthy pregnant mice.

Association of the presence of residual anti-Toxoplasma gondii IgM in pregnant women and their respective family groups in Miracema, Northwest Rio de Janeiro, Brazil

The seroprevalence of toxoplasmosis in 832 pregnant women in Miracema, Rio de Janeiro, was determined and 75.1 percent (625) and 2.0 percent (17) were anti-Toxoplasma gondii IgG and IgM positive, respectively. Out of the 17 IgM positive pregnant women, only one had low avidity IgG corresponding to the acute phase of the infection. All the other women presented with high avidity IgG and also presented with residual IgM anti-T. gondii. Of this sample, 106 received home visits (this includes 11 family nuclei of pregnant women with residual IgM anti-T. gondii, 68 nuclei of only IgG positive pregnant women and 27 nuclei of pregnant women with no antibodies to anti-T. gondii), resulting in 267 individuals visited. Out of these 267 individuals, 21 were positive for IgG and IgM anti-T. gondii and were candidates for the IgG avidity test. All of them presented with high avidity IgG and residual IgM. Five of these IgM+ individuals were (5/238; 2.1 percent) relatives of IgM negative pregnant women. The other 16 (16/29; 55.2 percent) were relatives of IgM+ pregnant women who were positive for residual IgM anti-T. gondii. This association was statistically significant (p = 0.0000). The analysis presented herein raises questions regarding the presence of residual IgM anti-T. gondii such as genetic determinants or even constant antigenic stimuli for the same family cluster.

O diagnóstico da toxoplasmose na gestante e no recém-nascido / Toxoplasmosis diagnosis in pregnangy and at the newborn

O diagnóstico da infecção produzida no homem pelo Toxoplasma gondii durante a gestação e o seu reconhecimento nos recem-nascidos é especialmente importante pela gravidade das lesões, muitas vezes definitivas...

Serological screening and toxoplasmosis exposure factors among pregnant women in South of Brazil

Screening sorológico e avaliação de fatores de risco para a transmissão de Toxoplasma gondii foi conduzido em 2.126 gestantes no sul do Brasil. Entre as gestantes avaliadas, 74,5% (n=1.583) mostraram anticorpos específicos contra Toxoplasma gondii. O contato com o solo foi o maior fator associado à infecção.

Chagas' disease: study of congenital transmission in cases of acute maternal infection

Se descrevem 3 gestantes com a doença de Chagas aguda. Duas gestantes infetadas no 3º trimestre de gestação não tiveram crianças infetadas. O 3º filho, doquella madre foi infetada no 1º trimestre, nasceu com doença de Chagas congénita. Estes resultados inducem a investigação sobre os fatores de riscos da transmição e sobre as desições médicas na conducção dos casos de gestantes com a doença de Chagas aguda.

Enfermedad de Chagas en Perú: transmisión congénita / Chagas disease in Peru: congenital transmission

American Trypanosomosis is an important parasitic infection in Peru. Human cases, reservoirs and vectors have been showed in two known geographic areas in the endemic zones: southwestern and northern and northeastern regions of the country; however vectors belonging to the three genera of triatominae: Triatoma, Panstrongylus and Rhodnius have been collected in almost all the territory. The serological surveys in blood banks in the southwestern region is 2-6% and human cases found out of the endemic areas show the possibility of congenital cases. The study of the prevalence is starting. This preliminary study performed on 3000 pregnant of Arequipa shows serological positives in 22 (0.7%) and only a newborn positive at IgM. This result indicates a probable low rate of congenital transmission and necessary to perform more studies.

Hallazgo de tripomastigoto en estudio citoquímico de líquido amniótico / Clinical finding of trypomastigote in citochemical study of amniotic fluid

Chagas disease is an important endemic disease in Latinamerica. The transmitions mechanism of Trypanosoma cruzi, etiologic agent of Chagas disease are multiples, this comunication is refering to congenital infection or transplacental infection. The aim of the present report was to describe the finding of trypomastigote in citochemical study of amniotic fluid from pregnant women with 32 weeks of gestation. Clinical findings of trypomastigote in amniotic fluid, shows the importance of microscopics tools in orger to detect and diagnose de Chagas disease in pregnant patients. Diagnosis of Chagas disease by citochemical study is an unreported and unexploited technique, easy to perform in an ordinary laboratory, allowing the possibility to explore events of early detection in the newborn

Effect of Chloroquine Prophylaxis on Birthweight and Malaria Parasite Load among pregnant women delivering in a regional hospital in Cameroon

This survey was conducted between December, 1997 and August, 1998 at the Chantal Biya Maternity Section of the Ebolowa Provincial Hospital, Cameroon. A total of 231 parturient mothers who gave birth to 232 neonates were included in the study. Ninety-five of them (41.1 percent) took anti-malaria prophylaxis (chroloquine) in the index pregnancy, and 136 (58.9 percent) did not. Both groups were similar with respect to socio-demographic characteristics except for educational level of the mother, which was significantly higher in the group on prophylaxis (x2 = 8.05; df = 2, p = 0.02). The overall prevalence of maternal parasitaemia was 37.2 percent. The group on chloroquine (TG) experienced a lesser parasitaemia (26.3 percent) than the non-prophylactic group (CG) (44.9 percent odds ratio (OR) = 2.28, CI = 1.24 - 4.19). The proportion of women with severe parasitaemia (>4000 parasites/ul) was also lower in the TG than CG (17.6 percent vs. 7.3 percent; OR = 2.69, CI = 1.04 - 7.23). A modest reduction in low birthweight was found in the TG which was not significant (23.4 percent vs 16.0 percent; p = 0.16). In conclusion, chloroquine given to prevent malaria in pregnancy was found to be effective in reducing peripheral malaria parasitaemia, but improvement in birthweight could not be demonstrated. Among other factors, impaired biological activity of the drug at the level of the placenta where parasite sequestration frequently occurs might be the explanation. We recommend that further investigation be carried out in the study area to evaluate this finding, and if confirmed, institute appropriate changes in the present policy of chloroquine prophylaxis in pregnancy.

Toxoplasmosis y aborto en evolución / Toxoplasmosis and abortion in evolution

Para conocer la prevalencia de toxoplasmosis en población abierta de Comitán Chiapas, se realizó estudio serológico por inmunofluorescncia indirecta en voluntarios sanos. Además se identifico la presencia de anticuerpos anti Toxoplasma gondii en 50 mujeres con aborto en evolución. Los resultados mostraron que alrededor de 5 por ciento de la población general tiene títulos positivos de anticuerpos anti Toxoplasma gondii, y el 18 por ciento en el caso de las mujeres con aborto en volución. Se concluyó que la seropositividad para esta parasitosis estadísticamente es signficativa en los casos de aborto que entre la población general (P<0.006) y también, es significativamente mayor a las mujeres con aborto, que con respecto a la mujeres de la población general de Comitán Chiapas (P<0.01)

Possible risk factors for vertical transmission of Chagas' disease

The author emphasizes the importance of the congenital transmission of Chagas' disease and discusses the possible risk factors for transmission such as age, origin, obstetrical history and maternal form of disease. Exacerbation of infection during pregnancy is also considered as a possible risk factor for transmission. Besides, a relationship between the frequency of transmission and gestational age is presented. Concerning breast-feeding, the risk of transmission is directly related to the acute phase of maternal disease and bleeding nipples

Avaliaçäo da parasitemia em mulheres portadoras de infecçäo pelo Trypanosoma cruzi durante e após a gestaçäo / Evaluation of parasitaemia in women who are carriers of Trypanosoma cruzi infection during and after pregnancy

Avaliou-se o perfil parasitêmico de 119 chagásicos crônicos, através de 828 xenodiagnósticos, realizados durante (465 xenos) e após a gravidez (363 xenos) visando rastrear uma possível variaçäo da parasitemia nesses períodos. A freqüência de xenos positivos foi maior durante a gestaçäo. Por outro lado, a freqüência de triatomíneos infectados foi, também maior durante a gravidez, indicando níveis parasitêmicos mais elevados neste período. Apenas 17 por cento das mäes estudadas tiveram dois ou mais xenos positivos durante a gravidez. Nestas mulheres, a diferença entre a freqüência de xenos positivos durante e após a gravidez foi elevada, sugerindo ter havido exacerbaçäo da infecçäo chagásica, pelo menos em algumas delas