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1.
Curr Pediatr Rev ; 18(1): 53-58, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34727860

RESUMO

BACKGROUND: Malaria is endemic in many states of India. Though there are reports of maternal and congenital malaria from endemic areas, however, there remains a paucity of data from hilly terrains. The present study evaluated the prevalence, clinical and microbiological spectrum of maternal and congenital malaria at a tertiary health care facility in Northern India over a period of 18 months. METHODS: In this observational study, mothers along with their newborns were evaluated for malaria by maternal, placental, and cord blood smear examination and rapid point-of-care diagnostic serological tests. Positive cases were confirmed by polymerase chain reaction. Mother-newborn duos were followed up till discharge from the hospital. RESULTS: A total of 843 mothers delivered during the study period and were screened along with their newborns and placentae. A total of Ten (1.18%) mothers had evidence of malarial parasitemia (Plasmodium vivax, n=7 and Pl. falciparum, n=3), however, none of the placental and cord blood samples were positive for malaria. Overall, 127 (15.1%) neonates required admission in neonatal intensive care unit for various morbidities. Incidence of small for gestational age (SGA) was high (n=210; 24.9%). Multivariate logistic regression analysis demonstrated maternal malaria to be an independent contributor for SGA [Odds Ratio (95% Confidence Interval), 10.7 (2.06 - 49.72)]. However, only 2% variance of SGA could be explained by maternal malaria alone. CONCLUSION: We report an encouragingly lower incidence of maternal malaria in mothers attending for delivery and a 'Zero' incidence for placental and congenital malaria during the study period as compared to national data (upto 7.4% in non-immune mothers), although maternal malaria could be a causative factor for SGA.


Assuntos
Malária , Mães , Feminino , Humanos , Índia/epidemiologia , Recém-Nascido , Malária/diagnóstico , Malária/epidemiologia , Parasitemia/congênito , Parasitemia/diagnóstico , Parasitemia/epidemiologia , Placenta , Gravidez
2.
Am J Trop Med Hyg ; 100(5): 1158-1163, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30860019

RESUMO

Despite recent large-scale investments, malaria remains a major public health concern. Few studies have examined congenital malaria, defined as the presence of malaria parasitemia within the first 7 days of life, in endemic areas. This study aimed to determine the prevalence, to describe the clinical presentation, and to examine factors associated with congenital malaria in newborns aged up to 7 days attending Tororo General Hospital in Uganda. A total of 261 mother/baby pairs were recruited in this cross-sectional study. Giemsa-stained thick blood smears for malaria parasites and rapid malaria diagnostic tests were performed on capillary blood samples from all newborns and mothers, as well as on placental and cord samples from newborns delivered in the hospital. The prevalence of congenital malaria in the newborns was 16/261 (6.1%). No single clinical feature was associated with congenital malaria. However, there were associations between congenital malaria and maternal parasitemia (P < 0.001), gravidity of one (P = 0.03), maternal age < 19 years (P = 0.01), cord blood parasitemia (P = 0.01), and placental malaria (P = 0.02). In conclusion, congenital malaria is not rare in Uganda and there are no obvious clinical features associated with it in the newborn. Based on these findings, we recommend strengthening malaria prevention during pregnancy to reduce the occurrence of congenital malaria in newborns.


Assuntos
Malária/congênito , Malária/epidemiologia , Parasitemia/congênito , Parasitemia/epidemiologia , Complicações Parasitárias na Gravidez/epidemiologia , Adolescente , Estudos Transversais , Feminino , Sangue Fetal/parasitologia , Hospitais Gerais , Humanos , Recém-Nascido , Doenças do Recém-Nascido/epidemiologia , Doenças do Recém-Nascido/parasitologia , Malária/sangue , Idade Materna , Mães/estatística & dados numéricos , Placenta/parasitologia , Gravidez , Complicações Parasitárias na Gravidez/prevenção & controle , Prevalência , Uganda , Adulto Jovem
4.
Malar J ; 13: 271, 2014 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-25015559

RESUMO

Albeit pregnancy-associated malaria (PAM) poses a potential risk for over 125 million women each year, an accurate review assessing the impact on malaria in infants has yet to be conducted. In addition to an effect on low birth weight (LBW) and prematurity, PAM determines foetal exposure to Plasmodium falciparum in utero and is correlated to congenital malaria and early development of clinical episodes during infancy. This interaction plausibly results from an ongoing immune tolerance process to antigens in utero, however, a complete explanation of this immune process remains a question for further research, as does the precise role of protective maternal antibodies. Preventive interventions against PAM modify foetal exposure to P. falciparum in utero, and have thus an effect on perinatal malaria outcomes. Effective intermittent preventive treatment in pregnancy (IPTp) diminishes placental malaria (PM) and its subsequent malaria-associated morbidity. However, emerging resistance to sulphadoxine-pyrimethamine (SP) is currently hindering the efficacy of IPTp regimes and the efficacy of alternative strategies, such as intermittent screening and treatment (IST), has not been accurately evaluated in different transmission settings. Due to the increased risk of clinical malaria for offspring of malaria infected mothers, PAM preventive interventions should ideally start during the preconceptual period. Innovative research examining the effect of PAM on the neurocognitive development of the infant, as well as examining the potential influence of HLA-G polymorphisms on malaria symptoms, is urged to contribute to a better understanding of PAM and infant health.


Assuntos
Malária/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Adulto , África Subsaariana/epidemiologia , Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Comorbidade , Ativação do Complemento , Deficiências do Desenvolvimento/etiologia , Deficiências do Desenvolvimento/imunologia , Combinação de Medicamentos , Resistência a Medicamentos , Feminino , Doenças Fetais/parasitologia , Doenças Fetais/prevenção & controle , Retardo do Crescimento Fetal/etiologia , Predisposição Genética para Doença , Infecções por HIV/epidemiologia , Antígenos HLA-G/genética , Antígenos HLA-G/imunologia , Humanos , Tolerância Imunológica , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/parasitologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Malária/congênito , Malária/tratamento farmacológico , Malária/embriologia , Malária/imunologia , Malária/prevenção & controle , Malária/transmissão , Malária Cerebral/complicações , Malária Cerebral/embriologia , Malária Cerebral/imunologia , Parasitemia/congênito , Parasitemia/epidemiologia , Parasitemia/transmissão , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/parasitologia , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Fatores de Risco , Natimorto/epidemiologia , Sulfadoxina/farmacologia , Sulfadoxina/uso terapêutico
5.
PLoS Negl Trop Dis ; 7(10): e2476, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24147166

RESUMO

BACKGROUND: According to the Chagas congenital transmission guides, the diagnosis of infants, born to Trypanosoma cruzi infected mothers, relies on the detection of parasites by INP micromethod, and/or the persistence of T. cruzi specific antibody titers at 10-12 months of age. METHODOLOGY AND PRINCIPAL FINDINGS: Parasitemia levels were quantified by PCR in T. cruzi-infected children, grouped according to the results of one-year follow-up diagnosis: A) Neonates that were diagnosed in the first month after delivery by microscopic blood examination (INP micromethod) (n = 19) had a median parasitemia of 1,700 Pe/mL (equivalent amounts of parasite DNA per mL); B) Infants that required a second parasitological diagnosis at six months of age (n = 10) showed a median parasitemia of around 20 Pe/mL and 500 Pe/mL at 1 and 6 months old, respectively, and C) babies with undetectable parasitemia by three blood microscopic observations but diagnosed by specific anti - T. cruzi serology at around 1 year old, (n = 22), exhibited a parasitemia of around 5 Pe/mL, 800 Pe/mL and 20 Pe/mL 1, 6 and 12 month after delivery, respectively. T. cruzi parasites were isolated by hemoculture from 19 congenitally infected children, 18 of which were genotypified as DTU TcV, (former lineage TcIId) and only one as TcI. SIGNIFICANCE: This report is the first to quantify parasitemia levels in more than 50 children congenitally infected with T. cruzi, at three different diagnostic controls during one-year follow-up after delivery. Our results show that the parasite burden in some children (22 out of 51) is below the detection limit of the INP micromethod. As the current trypanocidal treatment proved to be very effective to cure T. cruzi - infected children, more sensitive parasitological methods should be developed to assure an early T. cruzi congenital diagnosis.


Assuntos
Doença de Chagas/congênito , Doença de Chagas/diagnóstico , DNA de Protozoário/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Parasitemia/congênito , Parasitemia/diagnóstico , Trypanosoma cruzi/isolamento & purificação , DNA de Protozoário/genética , Diagnóstico Precoce , Feminino , Humanos , Lactente , Recém-Nascido , Carga Parasitária/métodos , Gravidez
6.
Malar J ; 12: 17, 2013 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-23311646

RESUMO

BACKGROUND: Congenital malaria is defined as malaria parasitaemia in the first week of life. The reported prevalence of congenital malaria in sub-Saharan Africa is variable (0 - 46%). Even though the clinical significance of congenital malaria parasitaemia is uncertain, anti-malarial drugs are empirically prescribed for sick newborns by frontline health care workers. Data on prevalence of congenital malaria in high-risk newborns will inform appropriate drug use and timely referral of sick newborns. METHODS: Blood samples of untreated newborns less than 1 week of age at the time of referral to Korle Bu Teaching hospital in Accra, Ghana during the peak malaria seasons (April to July) of 2008 and 2010 were examined for malaria parasites by, i) Giemsa-stained thick and thin blood smears for parasite count and species identification, ii) histidine-rich protein- and lactic dehydrogenase-based rapid diagnosis tests, or iii) polymerase chain reaction amplification of the merozoite surface protein 2 gene, for identification of sub-microscopic parasitaemia. Other investigations were also done as clinically indicated. RESULTS: In 2008, nine cases of Plasmodium falciparum parasitaemia were diagnosed by microscopy in 405 (2.2%) newborns. All the nine newborns had low parasite densities (≤ 50 per microlitre). In 2010, there was no case of parasitaemia by either microscopy or rapid diagnosis tests in 522 newborns; however, 56/467 (12%) cases of P. falciparum were detected by polymerase chain reaction. CONCLUSION: Congenital malaria is an uncommon cause of clinical illness in high-risk untreated newborns referred to a tertiary hospital in the first week of life. Empirical anti-malarial drug treatment for sick newborns without laboratory confirmation of parasitaemia is imprudent. Early referral of sick newborns to hospitals with resources and skills for appropriate care is recommended.


Assuntos
Malária Falciparum/congênito , Malária Falciparum/epidemiologia , Antígenos de Protozoários/sangue , Sangue/parasitologia , Estudos Transversais , DNA de Protozoário/sangue , Feminino , Gana/epidemiologia , Humanos , Imunoensaio , Recém-Nascido , Masculino , Microscopia , Parasitemia/congênito , Parasitemia/epidemiologia , Reação em Cadeia da Polimerase , Prevalência
7.
Malar J ; 11: 411, 2012 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-23217209

RESUMO

This is a report of the first Plasmodium vivax congenital malaria case in Guatemala and the first case in Latin America with genotypical, histological and clinical characterization. The findings show that maternal P. vivax infection still occurs in areas that are in the pathway towards malaria elimination, and can be associated with detrimental health effects for the neonate. It also highlights the need in very low transmission areas of not only maintaining, but increasing awareness of the problem and developing surveillance strategies, based on population risk, to detect the infection especially in this vulnerable group of the population.


Assuntos
Malária Vivax/congênito , Doenças Endêmicas , Feminino , Sangue Fetal/parasitologia , Guatemala/epidemiologia , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Malária Vivax/epidemiologia , Malária Vivax/transmissão , Parasitemia/congênito , Parasitemia/parasitologia , Plasmodium vivax/genética , Plasmodium vivax/isolamento & purificação , Vigilância da População , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/parasitologia , Adulto Jovem
8.
Trop Biomed ; 28(2): 339-42, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22041754

RESUMO

Congenital malaria is a condition rarely diagnosed, even in endemic countries. This tropical disease is associated with high mortality in the absence of timely recognition and prompt therapy, particularly when is due to Plasmodium falciparum, however Plasmodium vivax can also lead to relevant morbidity and mortality. We report an unusual case of a 19- day-old male newborn with neonatal vivax malaria, suspected primarily on the basis of positive maternal history, which presented with low birth weight, thrombocytopenia and a significant parasitemia. He responded satisfactorily to chloroquine antimalarial therapy, being successfully discharged 10 days after admission. Blood smears remained negative during the first 2 months of follow up. At 8 weeks of follow-up, she showed remarkable weight gain and was developing normally with age-appropriate anthropometry with no subsequent complications.


Assuntos
Malária Vivax/congênito , Plasmodium vivax/isolamento & purificação , Antimaláricos/administração & dosagem , Cloroquina/administração & dosagem , Humanos , Recém-Nascido , Malária Vivax/tratamento farmacológico , Masculino , Parasitemia/congênito , Parasitemia/tratamento farmacológico , Resultado do Tratamento
9.
Malar J ; 10: 239, 2011 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-21846373

RESUMO

BACKGROUND: Congenital malaria has been considered a rare event; however, recent reports have shown frequencies ranging from 3% to 54.2% among newborns of mothers who had suffered malaria during pregnancy. There are only a few references concerning the epidemiological impact of this entity in Latin-America and Colombia. OBJECTIVE: The aim of the study was to measure the prevalence of congenital malaria in an endemic Colombian region and to determine some of its characteristics. METHODS: A prospective, descriptive study was carried out in the mothers who suffered malaria during pregnancy and their newborns. Neonates were clinically evaluated at birth and screened for Plasmodium spp. infection by thick smear from the umbilical cord and peripheral blood, and followed-up weekly during the first 21 days of postnatal life through clinical examinations and thick smears. RESULTS: 116 newborns were included in the study and 80 umbilical cord samples were obtained. Five cases of congenital infection were identified (four caused by P. vivax and one by P. falciparum), two in umbilical cord blood and three in newborn peripheral blood. One case was diagnosed at birth and the others during follow-up. Prevalence of congenital infection was 4.3%. One of the infected newborns was severely ill, while the others were asymptomatic and apparently healthy. The mothers of the newborns with congenital malaria had been diagnosed with malaria in the last trimester of pregnancy or during delivery, and also presented placental infection. CONCLUSIONS: Congenital malaria may be a frequent event in newborns of mothers who have suffered malaria during pregnancy in Colombia. An association was found between congenital malaria and the diagnosis of malaria in the mother during the last trimester of pregnancy or during delivery, and the presence of placental infection.


Assuntos
Malária Falciparum/congênito , Malária Falciparum/epidemiologia , Malária Vivax/congênito , Malária Vivax/epidemiologia , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Adolescente , Adulto , Sangue/parasitologia , Colômbia/epidemiologia , Feminino , Humanos , Recém-Nascido , Malária Falciparum/diagnóstico , Malária Vivax/diagnóstico , Masculino , Parasitemia/congênito , Parasitemia/diagnóstico , Parasitemia/epidemiologia , Gravidez , Estudos Prospectivos , Adulto Jovem
10.
Eur J Immunol ; 40(4): 1062-72, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20039298

RESUMO

Placental malaria (PM), a frequent infection of pregnancy, provides an ideal opportunity to investigate the impact on immune development of exposure of the foetal immune system to foreign Ag. We investigated the effect of PM on the regulatory phenotype and function of cord blood cells from healthy Gambian newborns and peripheral blood cells from their mothers, and analyzed for effects on the balance between regulatory and effector responses. Using the gold standard for classifying PM we further distinguished between resolved infection and acute or chronic PM active at the time of delivery. We show that exposure to malarial Ag in utero results in the expansion of malaria-specific FOXP3(+) Treg and more generalized FOXP3(+) CD4(+) Treg in chronic and resolved PM, alongside increased Th1 pro-inflammatory responses (IFN-gamma, TNF-alpha, IFN-gamma:IL-10) in resolved PM infection only. These observations demonstrate a clear effect of exposure to malarial Ag in foetal life on the immune environment at birth, with a regulatory response dominating in the newborns with ongoing chronic PM, while those with resolved infection produce both regulatory and inflammatory responses. The findings might explain some of the adverse effects on the health of babies born to women with PM.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Sangue Fetal/imunologia , Doenças Fetais/imunologia , Feto/imunologia , Recém-Nascido/imunologia , Transmissão Vertical de Doenças Infecciosas , Malária Falciparum/imunologia , Parasitemia/imunologia , Doenças Placentárias/imunologia , Complicações Infecciosas na Gravidez/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Animais , Linfócitos T CD4-Positivos/química , Linfócitos T CD4-Positivos/metabolismo , Feminino , Sangue Fetal/parasitologia , Doenças Fetais/parasitologia , Fatores de Transcrição Forkhead/análise , Humanos , Recém-Nascido/sangue , Interferon gama/metabolismo , Interleucina-10/metabolismo , Malária Falciparum/congênito , Malária Falciparum/embriologia , Masculino , Parasitemia/congênito , Parasitemia/embriologia , Doenças Placentárias/parasitologia , Gravidez , Complicações Infecciosas na Gravidez/parasitologia , Subpopulações de Linfócitos T/química , Subpopulações de Linfócitos T/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
Emerg Infect Dis ; 15(5): 788-91, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19402971

RESUMO

Only 2 neonates with transplacentally or perinatally acquired (congenital) babesiosis have been reported. We describe a probable third congenital case of babesiosis in a 26-day-old infant; transmission was determined on the basis of a blood smear from the infant (15% parasitemia) and serologic results from the infant and mother.


Assuntos
Babesia/imunologia , Babesiose/congênito , Transmissão Vertical de Doenças Infecciosas , Parasitemia/congênito , Adulto , Animais , Babesiose/diagnóstico , Babesiose/parasitologia , Babesiose/transmissão , Feminino , Humanos , Recém-Nascido , New Jersey , Parasitemia/diagnóstico , Parasitemia/parasitologia , Parasitemia/transmissão , Gravidez
12.
Malar J ; 7: 117, 2008 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-18598342

RESUMO

BACKGROUND: Although recent reports on congenital malaria suggest that the incidence is increasing, it is difficult to determine whether the clinical disease is due to parasites acquired before delivery or as a result of contamination by maternal blood at birth. Understanding of the method of parasite acquisition is important for estimating the time incidence of congenital malaria and design of preventive measures. The aim of this study was to determine whether the first Plasmodium falciparum malaria disease in infants is due to same parasites present on the placenta at birth. METHODS: Babies born to mothers with P. falciparum parasites on the placenta detected by PCR were followed up to two years and observed for malaria episodes. Paired placental and infant peripheral blood samples at first malaria episode within first three months of life were genotyped (msp2) to determine genetic relatedness. Selected amplifications from nested PCR were sequenced and compared between pairs. RESULTS: Eighteen (19.1%) out of 95 infants who were followed up developed clinical malaria within the first three months of age. Eight pairs (60%) out of 14 pairs of sequenced placental and cord samples were genetically related while six (40%) were genetically unrelated. One pair (14.3%) out of seven pairs of sequenced placental and infants samples were genetically related. In addition, infants born from primigravidae mothers were more likely to be infected with P. falciparum (P < 0.001) as compared to infants from secundigravidae and multigravidae mothers during the two years of follow up. Infants from multigravidae mothers got the first P. falciparum infection earlier than those from secundigravidae and primigravidae mothers (RR = 1.43). CONCLUSION: Plasmodium falciparum malaria parasites present on the placenta as detected by PCR are more likely to result in clinical disease (congenital malaria) in the infant during the first three months of life. However, sequencing data seem to question the validity of this likelihood. Therefore, the relationship between placental parasites and first clinical disease need to be confirmed in larger studies.


Assuntos
Malária Falciparum/congênito , Malária Falciparum/epidemiologia , Plasmodium falciparum/isolamento & purificação , Adolescente , Adulto , Animais , Antígenos de Protozoários/genética , Feminino , Sangue Fetal/parasitologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/parasitologia , Transmissão Vertical de Doenças Infecciosas , Malária Falciparum/parasitologia , Malária Falciparum/transmissão , Pessoa de Meia-Idade , Parasitemia/congênito , Parasitemia/epidemiologia , Parasitemia/parasitologia , Parasitemia/transmissão , Placenta/parasitologia , Plasmodium falciparum/classificação , Plasmodium falciparum/genética , Reação em Cadeia da Polimerase , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/parasitologia , Prevalência , Proteínas de Protozoários/genética , Tanzânia/epidemiologia
13.
Invest Clin ; 44(3): 241-54, 2003 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-14552062

RESUMO

Research on this form of transmission was carried out on female rats intradermally injected, before mating, with 1 x 10(4) metacyclic trypomastigotes of T. cruzi strains from dog (Pr) and human (YBM). The infected rats, as well as their offspring, were given parasitological, immunological and histopathological examinations during and after gestation. Healthy gestating rats were used as controls. Rats infected with T. cruzi strains showed clear signs of infection between 18 and 45 days post-inoculation (pi). Of 44 offspring from mothers infected with Pr, 4 males (9.1%) showed high parasitemia (432 and 240 tryps./mm3 of blood) at 30 and 40 days after birth, while direct blood examination, hemoculture and xenodiagnosis showed no infection in the other 40, or in the 52 offspring of rats infected with YBM. Anti-T. cruzi antibodies were found in appreciable quantities in infected mothers and in 44 out of 92 (47.8%) of the offspring, with titers that fluctuated between 1:32 and 1:2048 respectively. Histopathological studies of rats sacrificed at the end of gestation showed acute myocarditis and myositis of varying intensity and extent, characterized by abundant inflammatory infiltrate, in some cases associated with nests of amastigotes. The placentas showed moderate cellular infiltrate without parasites in the vascular stroma and amniotic fluid. The offspring of mothers infected with Chagas' disease were reinoculated and showed an acute phase characterized by low parasitemia (p < 0.05); after 60 days, the beginnings of chronic myocarditis and myositis could be observed, of a similar intensity to that observed in offspring born to infected mothers that were subsequently infected. These results confirm that T. cruzi can be transmitted vertically in Wistar rats; that a small number of offspring contract Chagasic infection congenitally; that anti-T. cruzi antibodies can pass from the mother and that these can modify the immune response in the offspring; that the pathogenicity of the strains of T. cruzi plays an important role in congenital transmission independently of origin or geographical location.


Assuntos
Doença de Chagas/transmissão , Transmissão Vertical de Doenças Infecciosas , Parasitemia/parasitologia , Complicações Infecciosas na Gravidez/parasitologia , Doença Aguda , Líquido Amniótico/parasitologia , Animais , Animais Recém-Nascidos , Anticorpos Antiprotozoários/sangue , Cardiomiopatia Chagásica/parasitologia , Doença de Chagas/congênito , Doença de Chagas/imunologia , Doença de Chagas/parasitologia , Feminino , Imunidade Materno-Adquirida , Masculino , Músculo Esquelético/parasitologia , Parasitemia/congênito , Parasitemia/imunologia , Placenta/parasitologia , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Ratos , Ratos Wistar , Trypanosoma cruzi/imunologia , Trypanosoma cruzi/isolamento & purificação , Trypanosoma cruzi/patogenicidade
14.
Clin Exp Immunol ; 117(1): 130-7, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10403926

RESUMO

This study investigated the effect of maternal Onchocerca volvulus infection on humoral and cellular responsiveness in newborn children and their mothers. Onchocerca volvulus-specific IgG isotypes and IgE were significantly elevated in infected mothers and their infants. One year post partum, O. volvulus-specific IgG4 was strongly reduced in children of infected mothers, while IgG1 responses weakened only slightly. Umbilical cord mononuclear blood cells (UCBC) and peripheral blood cells (PBMC) from mothers proliferated in response to phytohaemagglutinin (PHA), concanavalin A (Con A), and the bacterial antigens streptolysin-O (SL-O) or purified protein derivative (PPD). UCBC from neonates born to O. volvulus-infected mothers responded lower (P < 0.01) to Con A (at 5 micrograms/ml), PPD (at 10 and 50 micrograms/ml) and O. volvulus-derived antigens (OvAg) (at 35 micrograms/ml), and in parallel, a diminished cellular reactivity (P < 0.01) by PBMC was observed to OvAg in mothers positive for O. volvulus. Several Th1-type (IL-2, IL-12, interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha)) and Th2-type (IL-4, IL-5, IL-10, IL-13) cytokines were secreted by UCBC and PBMC in response to OvAg, bacterial SL-O and PHA. OvAg did not stimulate IL-2 and none of the mitogens or antigens induced production of IL-4 in neonates. In response to OvAg, substantially elevated (P < 0.01) amounts of IFN-gamma were produced by UCBC from newborns of O. volvulus-infected mothers. UCBC secreted low levels of IL-5 and IL-13, while higher amounts of IL-10 were found (P < 0. 01) in newborns from onchocerciasis-free mothers. In conclusion, maternal O. volvulus-infection will sensitize in utero parasite-specific cellular immune responsiveness in neonates and activate OvAg-specific production of several Th1- and Th2-type cytokines.


Assuntos
Anticorpos Antiprotozoários/imunologia , Citocinas/biossíntese , Sangue Fetal/imunologia , Doenças Fetais/imunologia , Imunidade Materno-Adquirida , Onchocerca volvulus/imunologia , Oncocercose/congênito , Oncocercose/imunologia , Complicações Parasitárias na Gravidez/imunologia , Adolescente , Adulto , Animais , Anticorpos Antiprotozoários/biossíntese , Anticorpos Antiprotozoários/sangue , Citocinas/metabolismo , Suscetibilidade a Doenças , Feminino , Sangue Fetal/citologia , Humanos , Imunidade Celular , Imunoglobulina E/biossíntese , Imunoglobulina E/imunologia , Imunoglobulina G/biossíntese , Imunoglobulina G/imunologia , Recém-Nascido , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Microfilárias/isolamento & purificação , Pessoa de Meia-Idade , Onchocerca volvulus/isolamento & purificação , Oncocercose/embriologia , Oncocercose/epidemiologia , Parasitemia/congênito , Parasitemia/imunologia , Gravidez , Togo/epidemiologia
15.
J Parasitol ; 82(4): 635-7, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8691374

RESUMO

Until recently, congenital malaria was thought to be rare. Now, several reports suggest that more than 10% of newborns in some settings are parasitemic. The pathophysiology of transplacental transmission of Plasmodium is not well understood, and no animal model of congenital malaria exists. A rodent model of malaria in pregnant females, however, has been developed. In an effort to test the usefulness of this model in the study of congenital malaria, Wistar rats were injected intraperitoneally with approximately 10(6) NYU-2 strain Plasmodium berghei-infected erythrocytes at various times relative to conception. Perinatal maternal and neonatal blood was tested for the presence of parasites. Two rats infected preconceptually, 1 at 29 and the other at 11 days prior to mating, delivered aparasitemic pups. Fourteen rats were inoculated during gestation. Five of 5 rats infected on the fifth gestational day succumbed prior to delivery; 1 fetus was parasitemic. Offspring of females infected on the 9th, 10th, 12th, and 14th days of gestation were aparasitemic at birth. Four rats conceived after an initial Plasmodium infection had waned and were reinfected during pregnancy; none of their pups showed evidence of parasitemia. Thus, though rare, transplacental passage of malaria parasites can occur in rats. The Wistar rat-P. berghei model of gestational malaria, however, does not seem to be useful for the study of congenital malaria.


Assuntos
Modelos Animais de Doenças , Malária/congênito , Plasmodium berghei , Complicações Parasitárias na Gravidez , Ratos Wistar , Animais , Animais Recém-Nascidos , Feminino , Feto/parasitologia , Transmissão Vertical de Doenças Infecciosas , Malária/transmissão , Parasitemia/congênito , Gravidez , Ratos
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