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1.
Nature ; 582(7810): 104-108, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32427965

RESUMO

Malaria caused by Plasmodium falciparum remains the leading single-agent cause of mortality in children1, yet the promise of an effective vaccine has not been fulfilled. Here, using our previously described differential screening method to analyse the proteome of blood-stage P. falciparum parasites2, we identify P. falciparum glutamic-acid-rich protein (PfGARP) as a parasite antigen that is recognized by antibodies in the plasma of children who are relatively resistant-but not those who are susceptible-to malaria caused by P. falciparum. PfGARP is a parasite antigen of 80 kDa that is expressed on the exofacial surface of erythrocytes infected by early-to-late-trophozoite-stage parasites. We demonstrate that antibodies against PfGARP kill trophozoite-infected erythrocytes in culture by inducing programmed cell death in the parasites, and that vaccinating non-human primates with PfGARP partially protects against a challenge with P. falciparum. Furthermore, our longitudinal cohort studies showed that, compared to individuals who had naturally occurring anti-PfGARP antibodies, Tanzanian children without anti-PfGARP antibodies had a 2.5-fold-higher risk of severe malaria and Kenyan adolescents and adults without these antibodies had a twofold-higher parasite density. By killing trophozoite-infected erythrocytes, PfGARP could synergize with other vaccines that target parasite invasion of hepatocytes or the invasion of and egress from erythrocytes.


Assuntos
Apoptose/imunologia , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Malária Falciparum/imunologia , Malária Falciparum/prevenção & controle , Parasitos/imunologia , Plasmodium falciparum/citologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Adolescente , Adulto , Animais , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/química , Antígenos de Protozoários/imunologia , Aotidae/imunologia , Aotidae/parasitologia , Caspases/metabolismo , Criança , Estudos de Coortes , DNA de Protozoário/química , DNA de Protozoário/metabolismo , Ativação Enzimática , Eritrócitos/parasitologia , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Quênia , Vacinas Antimaláricas/imunologia , Malária Falciparum/parasitologia , Masculino , Camundongos , Parasitos/citologia , Parasitos/crescimento & desenvolvimento , Plasmodium falciparum/crescimento & desenvolvimento , Proteínas de Protozoários/química , Tanzânia , Trofozoítos/citologia , Trofozoítos/crescimento & desenvolvimento , Trofozoítos/imunologia , Vacúolos/imunologia
2.
J Infect Dis ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38942608

RESUMO

Immunomodulation enhances parasite fitness by reducing inflammation-induced morbidity in the mammalian host, as well as by attenuating parasite-targeting immune responses. Using a whole proteome differential screening method, we identified Schistosoma japonicum Helminth Defense Molecule (SjHDM-1) as a target of antibodies expressed by S. japonicum resistant, but not susceptible, individuals. In a longitudinal cohort study (N=644) conducted in a S. japonicum endemic region of the Philippines, antibody levels to SjHDM-1 did not predict resistance to reinfection but were associated with increased measures of inflammation. Individuals with high levels of anti-SjHDM-1 IgG had higher levels of C-reactive protein compared to individuals with low anti-SjHDM-1. High anti-SjHDM-1 IgG responses were also associated with reduced biomarkers of nutritional status (albumin), as well as decreased anthropometric measures of nutritional status (WAZ and HAZ) and increased measures of hepatomegaly. Our results suggest that anti-SjHDM-1 responses inhibit the immunomodulatory function of SjHDM-1, resulting in increased morbidity.

3.
Clin Infect Dis ; 78(1): 90-93, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-37585653

RESUMO

In a cross-sectional analysis of 354 Ugandan children (age 12-48 months) infected with Schistosoma mansoni, we assessed relationships between infection intensity and nutritional morbidities. Higher intensity was associated with an increased risk for anemia (RR = 1.05, 95% confidence interval [CI] 1.01-1.10) yet not associated with risk for underweight, stunting, or wasting.


Assuntos
Anemia , Esquistossomose mansoni , Criança , Animais , Humanos , Pré-Escolar , Lactente , Esquistossomose mansoni/complicações , Esquistossomose mansoni/epidemiologia , Uganda/epidemiologia , Estado Nutricional , Estudos Transversais , Prevalência , Schistosoma mansoni , Anemia/epidemiologia , Anemia/etiologia
4.
J Pediatr ; 269: 113977, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38401788

RESUMO

OBJECTIVE: To assess the impact and potential mechanistic pathways of prenatal alcohol exposure (PAE) on longitudinal growth and nutritional status in early childhood. STUDY DESIGN: A cohort of 296 mother-infant dyads (32% with PAE vs 68% unexposed) were recruited in Leyte, the Philippines, and followed from early gestation through 24 months of age. PAE was assessed using serum phosphatidylethanol (PEth) captured twice prenatally and in cord blood and supplemented with self-reported alcohol consumption. Linear mixed models were used to examine longitudinal effects of PAE on growth from birth through 2 years including key potential mediating factors (placental histopathology, and infant serum leptin and Insulin-like Growth Factor 1 [IGF-1]). RESULTS: After adjusting for potential confounders, we found that PAE was significantly associated with a delayed blunting of linear growth trajectories (height-for-age z-score, body length) and weight (weight-for-age z-score, body weight) that manifested between 4 and 6 months and continued through 12-24 months. PAE was also associated with a decreased rate of mid-upper-arm circumference growth from birth to 12 months, and a lower mean IGF-1 levels at birth and 6 months. CONCLUSION: This study demonstrates a delayed impact of PAE on growth that manifested around 6 months of age, underscoring the importance of routine clinical monitoring in early childhood. Furthermore, the findings supported prior animal model findings that suggest a mechanistic role for IGF-1 in PAE-induced growth delay.


Assuntos
Fator de Crescimento Insulin-Like I , Estado Nutricional , Efeitos Tardios da Exposição Pré-Natal , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/análise , Feminino , Filipinas/epidemiologia , Gravidez , Lactente , Masculino , Recém-Nascido , Estudos Longitudinais , Pré-Escolar , Consumo de Bebidas Alcoólicas/efeitos adversos , Desenvolvimento Infantil/efeitos dos fármacos , Adulto , Sangue Fetal/metabolismo , Sangue Fetal/química , Glicerofosfolipídeos/sangue , Peptídeos Semelhantes à Insulina
5.
Brain Behav Immun ; 118: 510-520, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38431237

RESUMO

Prenatal exposure to inflammation is related to the risk for cognitive impairment in offspring. However, mechanisms underlying the link between inflammatory cytokines at the maternal-fetal interface and human cognitive development are largely unknown. This study addressed this research gap by examining whether i) cytokines within the placenta are associated with different domains of neurocognitive development during infancy, and ii) if DHEA-S in cord blood mediates these associations. We also explored the role of early-life socioeconomic status (SES) in moderating the effect of fetal adrenal steroids on cognitive development in low- and middle-income country contexts. A cohort of 242 mother-infant dyads in Leyte, the Philippines participated in the study and all of them were followed from early pregnancy until 12-months. Concentrations of pro- and anti-inflammatory cytokines in the placenta, and DHEA-S in cord blood collected at delivery were evaluated. The multifactorial aspects of the infant's cognitive functioning were assessed based on the Bayley Scales of Infant Development, third edition (BSID-III). We used Structural Equation Modelling (SEM) with an orthogonal rotation to examine associated paths among latent variables of pro- and anti-inflammatory cytokines in the placenta, fetal neuroendocrine factors, and cognitive development. Pathway analyses showed that both pro- and anti-inflammatory cytokines in the placenta were indirectly related to cognitive (p < 0.05) and language developmental outcomes (p < 0.1) via DHEA-S in cord blood among the low SES group. Yet, we found no statistically significant indirect effect of pro- or anti-inflammatory cytokines on neurocognitive development among the high SES sub-sample. This study extends our understanding of how early-life socioeconomic conditions modify biological pathways underlying the relationship between prenatal factors and postpartum cognitive development.


Assuntos
Citocinas , Placenta , Lactente , Criança , Humanos , Gravidez , Feminino , Circulação Placentária , Filipinas , Cognição , Desidroepiandrosterona , Anti-Inflamatórios
6.
Trop Med Int Health ; 29(4): 334-342, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38356464

RESUMO

OBJECTIVES: Schistosomiasis is persistent in Lake Albert, Uganda, but local data are limited. This study aims to describe the local burden of moderate-to-heavy infection and associated morbidity in all ages and identify factors associated with these outcomes to guide further research. METHODS: This cross-sectional pilot study was conducted in July-August, 2022 in four village sites (Walukuba, Rwentale, Kyabarangwa and Runga) of the Praziquantel in Preschoolers (PIP) trial. Residents (approximately four per household) of any age of households of PIP participants were eligible, but individuals <10 years were only enrolled if no older individuals were available. Socio-demographic information, household location, single stool Kato-Katz and hepatic ultrasound results were obtained for a convenience sampled subset of trial households. The primary outcome, moderate-to-heavy infection (≥100 eggs per gram of faeces), was analysed using mixed-effects logistic regression, with a household random effect. Univariate analyses were used for the secondary outcome, periportal fibrosis (Niamey protocol ultrasound image pattern C-F). RESULTS: Of 243 participants with a median age of 22 (interquartile range 12-33) years from 66 households, 49.8% (103/207 with a Kato-Katz result) had moderate-to-heavy infection and 11.2% (25/224 with ultrasound data) had periportal fibrosis. Moderate-to-heavy infection clustered by household (intraclass correlation coefficient = 0.11) and, in multivariable analysis, varied by village (Walukuba vs. Kyabarangwa adjusted odds ratio [aOR] 0.11, 95% CI 0.02-0.71), was highest in participants aged 10-15 years (vs. 5-9 years aOR 6.14, 95% CI 1.61-23.38) and lower in those reporting praziquantel treatment in the past year (aOR 0.39, 95% CI 0.18-0.88). CONCLUSIONS: In this setting, schistosome infection and morbidity are pervasive in all age groups. More intensive interventions are needed, for example more frequent praziquantel treatment, under investigation in the PIP trial and improved water and sanitation. More research is needed to understand local treatment barriers and optimal control strategies.


Assuntos
Schistosoma mansoni , Esquistossomose mansoni , Adolescente , Adulto , Animais , Criança , Humanos , Adulto Jovem , Estudos Transversais , Fezes , Lagos , Cirrose Hepática , Morbidade , Projetos Piloto , Praziquantel/uso terapêutico , Prevalência , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Uganda/epidemiologia , Ensaios Clínicos como Assunto
7.
J Infect Dis ; 225(10): 1856-1860, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35091745

RESUMO

Hookworm infection is associated with poor nutritional outcomes, anemia, and impaired cognitive performance. We examined the association between maternal hookworm infection and birth outcomes in a cohort of women in Leyte, Philippines. We observed poor intrauterine growth characteristics associated with maternal hookworm only among male offspring, with lower birth weight, head circumference, and placental surface area. Male neonates also had higher insulin-like growth factor 2 (IGF-2) and lower adiponectin in cord blood. These data intriguingly suggest nutritional impacts of maternal hookworm infection during pregnancy may be divergent based on sex of the offspring.


Assuntos
Infecções por Uncinaria , Placenta , Peso ao Nascer , Feminino , Sangue Fetal , Infecções por Uncinaria/complicações , Humanos , Recém-Nascido , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Placenta/metabolismo , Gravidez
8.
J Infect Dis ; 223(7): 1265-1274, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33606021

RESUMO

Schistosomiasis remains a leading cause of chronic morbidity in endemic regions despite decades of widespread mass chemotherapy with praziquantel. Using our whole proteome differential screening approach, and plasma and epidemiologic data from a longitudinal cohort of individuals living in a Schistosoma japonicum-endemic region of the Philippines, we interrogated the parasite proteome to identify novel vaccine candidates for Schistosoma japonicum. We identified 16 parasite genes which encoded proteins that were recognized by immunoglobulin G or immunoglobulin E antibodies in the plasma of individuals who had developed resistance to reinfection, but were not recognized by antibodies in the plasma of individuals who remained susceptible to reinfection. Antibody levels to Sj6-8 and Sj4-1 measured in the entire cohort (N = 505) 1 month after praziquantel treatment were associated with significantly decreased risk of reinfection and lower intensity of reinfection over 18 months of follow-up.


Assuntos
Anticorpos Anti-Helmínticos , Schistosoma japonicum , Esquistossomose Japônica , Vacinas , Animais , Anticorpos Anti-Helmínticos/imunologia , Resistência à Doença , Humanos , Recidiva Local de Neoplasia , Praziquantel/uso terapêutico , Proteoma , Reinfecção/prevenção & controle , Schistosoma japonicum/genética , Esquistossomose Japônica/prevenção & controle
9.
J Infect Dis ; 222(4): 538-550, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32219317

RESUMO

BACKGROUND: Our objective was to quantify the risk of acquiring malaria among progeny of women with malaria during pregnancy. METHODS: We searched MEDLINE, EMBASE, CINAHL, and the Cochrane Library for eligible prospective studies. The primary predictor was malaria during pregnancy defined as placental malaria, parasitemia, clinical malaria, or pregnancy-associated malaria. Primary outcomes were parasitemia or clinically defined malaria of young children. We performed meta-analyses to pool adjusted risk estimates using a random-effects model. RESULTS: Nineteen of 2053 eligible studies met inclusion criteria for the systemic review. Eleven of these studies were quantitative and were included in the meta-analyses. The pooled adjusted odds ratio (aOR) or adjusted hazard ratio (aHR) of malaria during pregnancy for detection of parasitemia in young children were 1.94 (95% confidence interval [CI], 0.93-4.07; P = .08) and 1.46 (95% CI, 1.07-2.00; P < .001), respectively. The pooled aOR or aHR for clinically defined malaria in young children were 2.82 (95% CI, 1.82-4.38; P < .001) and 1.31 (95% CI, 0.96-1.79; P = .09), respectively. CONCLUSIONS: Our results confirmed that malaria during pregnancy significantly increased the overall risk of malaria in young children via indeterminate mechanisms and emphasize the urgent need to implement safe and highly effective strategies to prevent malaria during pregnancy.


Assuntos
Número de Gestações , Transmissão Vertical de Doenças Infecciosas , Malária/transmissão , Feminino , Humanos , Lactente , Parasitemia , Placenta/parasitologia , Gravidez , Fatores de Risco
10.
Artigo em Inglês | MEDLINE | ID: mdl-32631820

RESUMO

An estimated 40 million women of reproductive age are infected with one of three species of the waterborne parasite Schistosoma spp. Treatment with praziquantel (PZQ) via mass drug administration (MDA) campaigns is the mainstay of schistosomiasis control for populations living in areas of endemicity. The World Health Organization recommends that pregnant and lactating women be included in schistosomiasis MDA programs, and several recent studies have evaluated the safety and efficacy of PZQ use during pregnancy. To date, there are no data describing PZQ pharmacokinetics (PK) during pregnancy or among lactating postpartum women. As part of a randomized controlled trial investigating the safety and efficacy of PZQ during human pregnancy, we examined the PK of this therapeutic drug among three distinct cohorts of women infected with S. japonicum in Leyte, Philippines. Specifically, we studied the PK properties of PZQ among early- and late-gestation pregnant women (n = 15 each) and lactating postpartum women (n = 15) with schistosomiasis. We found that women in early pregnancy had increased apparent clearance and lower area-under-the-curve (AUC0-24) values that may be related to physiological changes in drug clearance and/or changes in oral bioavailability. There was no relationship between body weight and apparent clearance. The mean ± standard deviation partition ratio of plasma to breast milk was 0.36. ± 0.13. The estimated median infant PZQ daily dose would be 0.037 mg/kg of body weight ingested from breast milk, which is significantly lower than the dosage required for antischistosomal activity and not known to be harmful to the infant. Our PK data do not support the suggestion to delay breastfeeding 72 h after taking PZQ. Results can help inform future drug efficacy studies in pregnant and lactating women with schistosomiasis.


Assuntos
Anti-Helmínticos , Schistosoma japonicum , Esquistossomose , Animais , Anti-Helmínticos/uso terapêutico , Feminino , Humanos , Lactação , Filipinas , Praziquantel/uso terapêutico , Gravidez , Schistosoma mansoni , Esquistossomose/tratamento farmacológico
11.
Clin Infect Dis ; 68(10): 1718-1724, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-30165569

RESUMO

BACKGROUND: In holoendemic areas, children suffer the most from Plasmodium falciparum malaria, yet newborns and young infants express a relative resistance to both infection and severe malarial disease (SM). This relative resistance has been ascribed to maternally-derived anti-parasite immunoglobulin G; however, the targets of these protective antibodies remain elusive. METHODS: We enrolled 647 newborns at birth from a malaria-holoendemic region of Tanzania. We collected cord blood, measured antibodies to Plasmodium falciparum Schizont Egress Antigen-1 (PfSEA-1), and related these antibodies to the risk of severe malaria in the first year of life. In addition, we vaccinated female mice with PbSEA-1, mated them, and challenged their pups with P. berghei ANKA parasites to assess the impact of maternal PbSEA-1 vaccination on newborns' resistance to malaria. RESULTS: Children with high cord-blood anti-PfSEA-1 antibody levels had 51.4% fewer cases of SM compared to individuals with lower anti-PfSEA-1 levels over 12 months of follow-up (P = .03). In 3 trials, pups born to PbSEA-1-vaccinated dams had significantly lower parasitemia and longer survival following a P. berghei challenge compared to pups born to control dams. CONCLUSIONS: We demonstrate that maternally-derived, cord-blood anti-PfSEA-1 antibodies predict decreased risk of SM in infants and vaccination of mice with PbSEA-1 prior to pregnancy protects their offspring from lethal P. berghei challenge. These results identify, for the first time, a parasite-specific target of maternal antibodies that protect infants from SM and suggest that vaccination of pregnant women with PfSEA-1 may afford a survival advantage to their offspring.


Assuntos
Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Sangue Fetal/imunologia , Imunidade Materno-Adquirida , Malária Falciparum/prevenção & controle , Proteínas de Protozoários/imunologia , Índice de Gravidade de Doença , Animais , Antígenos de Protozoários/administração & dosagem , Estudos de Coortes , Resistência à Doença , Feminino , Humanos , Imunoglobulina G/sangue , Lactente , Recém-Nascido , Malária Falciparum/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Parasitemia/imunologia , Parasitemia/prevenção & controle , Plasmodium berghei/imunologia , Plasmodium falciparum , Proteínas de Protozoários/administração & dosagem , Tanzânia , Vacinação
12.
Pediatr Res ; 86(3): 396-402, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31129681

RESUMO

BACKGROUND: We evaluated the association between etiology of maternal anemia and iron status throughout infancy. METHODS: Samples from a study designed to examine Praziquantel treatment during pregnancy were used (n = 359). All women were infected with schistosomiasis and randomized to Praziquantel or placebo at 16 ± 2 weeks' gestation. Hemoglobin, serum ferritin (SF), soluble transferrin receptor (sTfR), hepcidin, C-reactive protein, and interleukin-6 were measured in maternal and infant blood. The relationship between both maternal Praziquantel treatment and etiology of anemia and infant iron status was evaluated. RESULTS: Maternal iron-deficiency anemia was associated with increased risk of infant anemia at 6 months of age. Infants of mothers with the lowest levels of circulating hepcidin during gestation, likely a marker for iron deficiency, had higher sTfR:SF levels and lower hemoglobin levels, particularly at 12 months of age. Maternal non-iron-deficiency anemia (NIDA) did not impact infant anemia risk or iron status. Maternal treatment for schistosomiasis had no effect on infant hematologic status. CONCLUSIONS: Maternal iron deficiency anemia was associated with an increased risk for anemia or iron deficiency during late infancy. We did not observe an association between maternal NIDA and increased risk for iron deficiency during infancy.


Assuntos
Anemia/diagnóstico , Anemia/genética , Ferro/sangue , Complicações Hematológicas na Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Esquistossomose/tratamento farmacológico , Anti-Helmínticos/efeitos adversos , Anti-Helmínticos/farmacologia , Antígenos CD/sangue , Proteína C-Reativa/análise , Feminino , Ferritinas/sangue , Hemoglobinas/análise , Hepcidinas/sangue , Humanos , Recém-Nascido , Doenças do Recém-Nascido , Interleucina-6/sangue , Deficiências de Ferro , Masculino , Exposição Materna , Filipinas , Praziquantel/efeitos adversos , Praziquantel/farmacologia , Gravidez , Resultado da Gravidez , Receptores da Transferrina/sangue , Esquistossomose/complicações
13.
Bull World Health Organ ; 96(1): 59-65, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29403101

RESUMO

In 2014, an estimated 40 million women of reproductive age were infected with Schistosoma haematobium, S. japonicum and/or S. mansoni. In both 2003 and 2006, the World Health Organization (WHO) recommended that all schistosome-infected pregnant and breastfeeding women be offered treatment, with praziquantel, either individually or during treatment campaigns. In 2006, WHO also stated the need for randomized controlled trials to assess the safety and efficacy of such treatment. Some countries have yet to follow the recommendation on treatment and many programme managers and pregnant women in other countries remain reluctant to follow the recommended approach. Since 2006, two randomized controlled trials on the use of praziquantel during pregnancy have been conducted: one against S. mansoni in Uganda and the other against S. japonicum in the Philippines. In these trials, praziquantel treatment of pregnant women had no significant effect on birth weight, appeared safe and caused minimal side-effects that were similar to those seen in treated non-pregnant subjects. Having summarized the encouraging data, on efficacy, pharmacokinetics and safety, from these two trials and reviewed the safety data from non-interventional human studies, we recommend that all countries include pregnant women in praziquantel treatment campaigns. We identify the barriers to the treatment of pregnant women, in countries that already include such women in individual treatments and mass drug administration campaigns, and discuss ways to address these barriers.


En 2014, on estimait que 40 millions de femmes en âge de procréer étaient infectées par Schistosoma haematobium, S. japonicum et/ou S. mansoni. En 2003 et 2006, l'Organisation mondiale de la Santé (OMS) a recommandé qu'un traitement au praziquantel soit offert, individuellement ou dans le cadre de campagnes de traitement, à toutes les femmes enceintes et allaitantes infectées par le schistosome. En 2006, l'OMS a également affirmé la nécessité d'essais contrôlés randomisés pour évaluer l'innocuité et l'efficacité de ce traitement. Néanmoins, certains pays ne suivent toujours pas la recommandation relative au traitement et dans d'autres pays, bon nombre de gestionnaires de programme et de femmes enceintes demeurent réticents à suivre l'approche recommandée. Depuis 2006, deux essais contrôlés randomisés sur l'utilisation du praziquantel au cours de la grossesse ont été menés: l'un sur S. mansoni en Ouganda et l'autre sur S. japonicum aux Philippines. Dans le cadre de ces essais, le traitement au praziquantel des femmes enceintes n'a pas eu d'effet notable sur le poids à la naissance, s'est révélé sans danger et a provoqué des effets secondaires minimes, similaires à ceux constatés chez les femmes traitées qui n'étaient pas enceintes. Ayant résumé les données encourageantes sur l'efficacité, la pharmacocinétique et l'innocuité tirées de ces deux essais et examiné les données de sécurité provenant d'études non interventionnelles sur l'homme, nous recommandons que tous les pays incluent les femmes enceintes dans des campagnes de traitement au praziquantel. Nous mettons en évidence les obstacles qui empêchent le traitement des femmes enceintes ­ dans des pays les incluant déjà dans des traitements individuels et des campagnes d'administration massive de médicaments ­ et décrivons des moyens permettant de surmonter ces obstacles.


En 2014, se estima que 40 millones de mujeres en edad reproductiva estaban infectadas con Schistosoma haematobium, S. japonicum y/o S. mansoni. Tanto en 2003 como en 2006, la Organización Mundial de la Salud (OMS) recomendó que todas las mujeres embarazadas y lactantes infectadas con esquistosoma recibieran tratamiento, con praziquantel, ya fuera individualmente o durante las campañas de tratamiento. En 2006, la OMS también informó de la necesidad de ensayos aleatorizados controlados para evaluar la seguridad y la eficacia de dicho tratamiento. Algunos países todavía tienen que seguir la recomendación sobre el tratamiento y muchos gestores de programas y mujeres embarazadas en otros países siguen siendo reacios a seguir el enfoque recomendado. Desde 2006, se han llevado a cabo dos ensayos aleatorizados controlados sobre el uso de praziquantel durante el embarazo: uno contra el S. mansoni en Uganda y el otro contra el S. japonicum en Filipinas. En estos ensayos, el tratamiento con praziquantel en mujeres embarazadas no tuvo un efecto significativo sobre el peso en el momento del nacimiento, pareció seguro y causó efectos secundarios mínimos, similares a los observados en sujetos no embarazadas tratadas. Después de resumir los alentadores datos sobre la eficacia, la farmacocinética y la seguridad de estos dos ensayos y revisar los datos de seguridad de los estudios observacionales en humanos, recomendamos que todos los países incluyan a mujeres embarazadas en las campañas de tratamiento con praziquantel. Identificamos las barreras para el tratamiento de mujeres embarazadas, en países que ya incluyen a mujeres en los tratamientos individuales y en las campañas masivas de administración de medicamentos, y analizamos las formas de abordar estas barreras.


Assuntos
Anti-Helmínticos/uso terapêutico , Praziquantel/uso terapêutico , Complicações Parasitárias na Gravidez/tratamento farmacológico , Schistosoma japonicum/efeitos dos fármacos , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose/tratamento farmacológico , Animais , Feminino , Humanos , Filipinas , Gravidez , Complicações Parasitárias na Gravidez/diagnóstico , Schistosoma japonicum/isolamento & purificação , Schistosoma mansoni/isolamento & purificação , Esquistossomose/diagnóstico , Resultado do Tratamento , Uganda
14.
J Nutr ; 148(3): 427-436, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29546300

RESUMO

Background: To our knowledge, no studies have addressed whether maternal anemia of inflammation (AI) affects newborn iron status, and few have addressed risk factors for specific etiologies of maternal anemia. Objectives: The study aims were to evaluate 1) the contribution of AI and iron deficiency anemia (IDA) to newborn iron endowment, 2) hepcidin as a biomarker to distinguish AI from IDA among pregnant women, and 3) risk factors for specific etiologies of maternal anemia. Methods: We measured hematologic biomarkers in maternal blood at 12 and 32 wk of gestation and in cord blood from a randomized trial of praziquantel in 358 pregnant women with Schistosoma japonicum in The Philippines. IDA was defined as anemia with serum ferritin <30 ng/mL and non-IDA (NIDA), largely due to AI, as anemia with ferritin ≥30 ng/mL. We identified cutoffs for biomarkers to distinguish IDA from NIDA by using area under the curve (AUC) analyses and examined the impact of different causes of anemia on newborn iron status (primary outcome) by using multivariate regression modeling. Results: Of the 358 mothers, 38% (n = 136) had IDA and 9% (n = 32) had NIDA at 32 wk of gestation. At 32 wk of gestation, serum hepcidin performed better than soluble transferrin receptor (sTfR) in identifying women with NIDA compared with the rest of the cohort (AUCs: 0.75 and 0.70, respectively) and in identifying women with NIDA among women with anemia (0.73 and 0.72, respectively). The cutoff that optimally distinguished women with NIDA from women with IDA in our cohort was 6.1 µg/L. Maternal IDA, but not NIDA, was associated with significantly lower newborn ferritin (114.4 ng/mL compared with 148.4 µg/L; P = 0.042). Conclusions: Hepcidin performed better than sTfR in identifying pregnant women with NIDA, but its cost may limit its use. Maternal IDA, but not NIDA, is associated with decreased newborn iron stores, emphasizing the need to identify this cause and provide iron therapy. This trial was registered at www.clinicaltrials.gov as NCT00486863.


Assuntos
Anemia/etiologia , Ferritinas/sangue , Hepcidinas/sangue , Saúde do Lactente , Inflamação/complicações , Ferro/sangue , Complicações na Gravidez/sangue , Adulto , Anemia/sangue , Anemia Ferropriva/sangue , Anemia Ferropriva/etiologia , Animais , Área Sob a Curva , Biomarcadores/sangue , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Inflamação/sangue , Deficiências de Ferro , Mães , Estado Nutricional , Gravidez , Complicações na Gravidez/etiologia , Receptores da Transferrina/sangue , Valores de Referência , Fatores de Risco , Schistosoma japonicum , Adulto Jovem
15.
Br Med Bull ; 123(1): 115-125, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28910994

RESUMO

Background: In endemic areas, schistosomiasis causes both overt and subclinical disease in young children and their mothers, as well as in returned travellers. Sources of data: Key recently published literature. Areas of agreement: An action plan for paediatric schistosomiasis and female genital schistosomiasis (FGS) is needed with expanded access to praziquantel (PZQ) treatment required. Areas of controversy: Schistosomiasis-related morbidity is underappreciated. Present and future demand for PZQ treatment is bottlenecked, imbalanced and inequitable. Current dosing, treatment algorithms and access plans are suboptimal with treatment stalled during pregnancy. Growing points: Raised dosing of PZQ (>40 mg/kg) is being explored in young children. Surveillance of female genital schistosomiasis FGS is increasing. Use of PZQ in pregnancy is safe and preventive chemotherapy guidelines are being revised in morbidity- and transmission-control settings. Areas timely for developing research: Shifting focus of population-level control to individual-case management. Detection and prevention of FGS within general health services and integration of PZQ treatment for women and children in antenatal clinics. Feasibility studies assessing alternative and expanded access to PZQ treatment to at-risk children and mothers and pregnant women.


Assuntos
Anti-Helmínticos/uso terapêutico , Praziquantel/uso terapêutico , Esquistossomose/tratamento farmacológico , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/provisão & distribuição , Criança , Doenças Transmissíveis Importadas , Feminino , Humanos , Praziquantel/administração & dosagem , Praziquantel/provisão & distribuição , Gravidez , Complicações Parasitárias na Gravidez/tratamento farmacológico , Esquistossomose/transmissão
16.
J Infect Dis ; 209(3): 468-72, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23964108

RESUMO

Schistosomiasis affects approximately 40 million women of reproductive age and has been linked to elevated levels of circulating endotoxin in nonpregnant individuals. We have evaluated endotoxin levels in maternal, placental, and newborn blood collected from women residing in Leyte, Philippines. Endotoxin levels in both maternal and placental compartments in pregnant women with schistosomiasis were 1.3- and 2.4-fold higher, respectively, than in uninfected women. In addition, higher concentrations of endotoxin in placental blood were associated with premature birth, acute chorioamnionitis, and elevated proinflammatory cytokines. By promoting endotoxemia, schistosomiasis may exert additional, maladaptive influences on pregnancy outcomes.


Assuntos
Análise Química do Sangue , Endotoxinas/sangue , Sangue Fetal/química , Complicações Parasitárias na Gravidez/patologia , Esquistossomose Japônica/patologia , Adulto , Citocinas/sangue , Feminino , Humanos , Recém-Nascido , Filipinas , Gravidez
17.
Infect Immun ; 82(1): 350-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24166958

RESUMO

The global burden of schistosomiasis is significant, with fibrosis a major associated morbidity and the primary cause of mortality. We have previously shown that schistosomiasis during pregnancy upregulates proinflammatory cytokines in the cord blood. In this study, we extend these findings to include a large panel of fibrosis-associated markers. We developed a multiplex bead-based assay to measure the levels of 35 proteins associated with fibrosis. Cord blood from 109 neonates born to mothers residing in an area of Schistosoma japonicum endemicity was assessed for these molecules. Ten mediators were elevated in the cord blood from schistosome-infected pregnancies, including insulin-like growth factor 1 (IGF-1), tumor growth factor ß1 (TGF-ß1), connective tissue growth factor (CTGF), procollagen I carboxy-terminal propeptide (PICP), amino-telopeptide of type 1 collagen (ICTP), collagen VI, desmosine, matrix metalloproteinase 2 (MMP-2), tissue inhibitor of metalloproteinases 1 (TIMP-1), and TIMP-4. Many of these were also positively correlated with preterm birth (PICP, ICTP, MMP-2, TGF-ß1, desmosine, CTGF, TIMP-1). In addition, birth weight was 168 g lower for infants with detectable levels of CTGF than for those with CTGF levels below the level of detection. Maternal schistosomiasis results in upregulation of fibrosis-associated proteins in the cord blood of the neonate, a subset of which are also associated with adverse birth outcomes. As the first report of fibrosis-associated molecules altered in the newborn of infected mothers, this study has broad implications for the health of the fetus, stretching from gestation to adulthood.


Assuntos
Sangue Fetal/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Cirrose Hepática/parasitologia , Schistosoma japonicum/fisiologia , Esquistossomose Japônica/sangue , Animais , Biomarcadores/sangue , Peso ao Nascer/fisiologia , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Cirrose Hepática/sangue , Filipinas , Gravidez , Complicações Parasitárias na Gravidez , Nascimento Prematuro , Esquistossomose Japônica/patologia
18.
Int J Gynaecol Obstet ; 164(2): 750-757, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37589399

RESUMO

OBJECTIVE: Poor intrauterine growth has negative impacts for child growth and development and disproportionately affects children living in low-resource settings. In the present study, we investigated relationships between placental pathologies and indicators of poor intrauterine growth. METHODS: We enrolled a longitudinal cohort of 279 mother-infant pairs from Leyte, the Philippines. Placental measures included characteristics, pathological findings, and immunohistochemistry. At birth, intrauterine growth was assessed using anthropometric measures, weight-for-gestational age, and the clinical assessment of nutritional status score (CANSCORE) for determining fetal malnutrition. Multivariate linear regression and log-binomial regression models were applied, controlling for potential confounding factors. RESULTS: Maternal vascular malperfusion (MVM) was related to reduced birthweight (P < 0.0001), birth length (P = 0.002), head circumference (P = 0.001), and weight-to-length ratio (P = 0.016). MVM increased the risk for preterm delivery (P = 0.0005) and small for gestational age (SGA) (P = 0.016). Acute chorioamnionitis (P = 0.013) and MVM (P = 0.021) both led to an increased risk for fetal malnutrition defined by CANSORE<25. Villous tissue activated caspase-3 was associated with lower birth length (P = 0.0006), higher weight-to-length ratio (P = 0.004), reduced risks for SGA (P = 0.011) and low weight-to-length ratio for gestational age (P = 0.004). CONCLUSION: The present study applied comprehensive measures for intrauterine growth and demonstrates that low placental weight and placental pathology, chiefly MVM, contribute to poor intrauterine growth. A better understanding of the mechanistic role of specific placental pathologies on adverse newborn outcomes will provide opportunities for reducing incidence of poor intrauterine growth and associated long-term morbidities.


Assuntos
Transtornos da Nutrição Fetal , Placenta , Recém-Nascido , Criança , Gravidez , Feminino , Humanos , Placenta/irrigação sanguínea , Resultado da Gravidez/epidemiologia , Mães , Transtornos da Nutrição Fetal/patologia , Filipinas/epidemiologia , Estudos Retrospectivos , Retardo do Crescimento Fetal/epidemiologia , Retardo do Crescimento Fetal/etiologia
19.
Sci Rep ; 14(1): 8164, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589377

RESUMO

Schistosoma japonicum is endemic in the Philippines. The Kato-Katz (KK) method was used to diagnose S. japonicum. This is impractical, particularly when the sample size is limited. Knowledge on point-of-care circulating cathodic antigen (CCA) test performance for S. japonicum is limited. Determining the sensitivity and specificity of new diagnostics is difficult when the gold standard test is less effective or absent. Latent class analysis (LCA) can address some limitations. A total of 484 children and 572 adults from the Philippines were screened for S. japonicum. We performed Bayesian LCA to estimate the infection prevalence, sensitivity and specificity of each test by stratifying them into two age groups. Observed prevalence assessed by KK was 50.2% and 31.8%, and by CCA was 89.9% and 66.8%, respectively. Using Bayesian LCA, among children, the sensitivity and specificity of CCA were 94.8% (88.7-99.4) and 21.5% (10.5-36.1) while those of KK were 66.0% (54.2-83.3) and 78.1% (61.1-91.3). Among adults, the sensitivity and specificity of CCA were 86.4% (76.6-96.9) and 62.8% (49.1-81.1) while those of KK were 43.6% (35.1-53.9) and 85.5% (75.8-94.6). Overall, CCA was more sensitive than KK, regardless of the age group at diagnosis, as KK was more specific. KK and CCA have different diagnostic performance, which should inform their use in the planning and implementation of S. japonicum control programs.


Assuntos
Schistosoma japonicum , Esquistossomose mansoni , Criança , Adulto , Animais , Humanos , Schistosoma mansoni , Antígenos de Helmintos , Teorema de Bayes , Análise de Classes Latentes , Sistemas Automatizados de Assistência Junto ao Leito , Fezes/química , Sensibilidade e Especificidade , Prevalência
20.
Pediatr Infect Dis J ; 43(1): 14-20, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37922490

RESUMO

BACKGROUND: Periportal fibrosis is a late-stage manifestation of chronic infection with Schistosoma mansoni . Praziquantel (PZQ), the only drug available for the treatment of schistosomiasis, has limited effect in treating established morbidity. Preschool-age children (PSAC) are not considered to be an at-risk population for severe morbidity. However, the prevalence of periportal fibrosis in PSAC in S. mansoni endemic settings is unknown. METHODS: As part of a phase II clinical trial comparing different dosing regimens of PZQ in children age 12-47 months infected with S. mansoni in Uganda ("praziquantel in preschoolers" trial), we present baseline results assessing liver ultrasound (US) findings as per the WHO Niamey Protocol. RESULTS: A total of 7/347 (2%) PSAC had Image Pattern C with pipe stems and echogenic rings suggestive of periportal fibrosis, 29/347 (8%) had Image Pattern B and 58 (17%) had evidence of periportal thickening There were higher adjusted odds of periportal thickening with older age [odds ratio (OR): 1.04; 95% confidence interval (CI): 1.00-1.07], primary maternal education (OR: 1.04; 95% CI: 1.00-1.07) and being taken to the lake weekly (OR: 3.02; 95% CI: 1.19-7.63). A further 44/347 children (13%) had a rounded caudal liver edge which was associated with high S. mansoni infection intensity (adjusted OR: 3.31; 95% CI: 1.46-7.51). CONCLUSIONS: Incipient schistosomiasis-related liver morbidity was detected in young children enrolled in the praziquantel in preschoolers trial. Adequate age-adjusted reference measurements for liver ultrasound findings in very small children are lacking but urgently needed. Schistosomiasis-related fibrosis may be delayed or averted with early and repeated PZQ treatment.


Assuntos
Anti-Helmínticos , Esquistossomose mansoni , Esquistossomose , Pré-Escolar , Humanos , Lactente , Praziquantel/uso terapêutico , Anti-Helmínticos/uso terapêutico , Uganda/epidemiologia , Lagos , Esquistossomose mansoni/diagnóstico por imagem , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Esquistossomose/tratamento farmacológico , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/tratamento farmacológico
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