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1.
Pediatrics ; 151(4)2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36861307

RESUMO

BACKGROUND: Cerebral malaria (CM) and severe malarial anemia (SMA) are associated with neurocognitive impairment in childhood but their effects on long-term academic achievement are not known. METHODS: Ugandan children 5 to 12 years old who participated in a previous study evaluating cognitive outcomes after CM (n = 73) or SMA (n = 56), along with community children (CC, n = 100) from the same household or neighborhood, were on average enrolled 67.1 months (range, 19-101 months) after the severe malaria episode or previous study enrollment. Academic achievement in word reading, sentence comprehension, spelling, and math computation was evaluated using the Wide Range Achievement Test, Fourth Edition. Age-adjusted z-scores for academic achievement outcomes were calculated from CC scores. RESULTS: After adjustment for age and time from enrollment, reading scores were lower (mean difference from CC [95% confidence interval]) in children with CM (-0.15 [-0.27 to -0.03], P = .02) or SMA (-0.15 [-0.28 to -0.02], P = .02) than CC. Postdischarge malaria episodes were associated with worse spelling and reading scores in CM and worse spelling scores only in SMA. Pathway analysis showed that incidence of postdischarge uncomplicated malaria contributed significantly to the association of CM or SMA with poorer reading scores. CONCLUSION: Children with CM or SMA have poorer long-term reading skills. Postdischarge malaria episodes contribute significantly to this association. Postdischarge malaria chemoprevention should be assessed as an intervention to improve long-term academic achievement in children with severe malaria.


Assuntos
Sucesso Acadêmico , Anemia , Malária Cerebral , Criança , Humanos , Pré-Escolar , Assistência ao Convalescente , Alta do Paciente , Malária Cerebral/epidemiologia , Anemia/complicações
2.
BMC Med ; 20(1): 28, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35081974

RESUMO

BACKGROUND: Understanding the age patterns of disease is necessary to target interventions to maximise cost-effective impact. New malaria chemoprevention and vaccine initiatives target young children attending routine immunisation services. Here we explore the relationships between age and severity of malaria hospitalisation versus malaria transmission intensity. METHODS: Clinical data from 21 surveillance hospitals in East Africa were reviewed. Malaria admissions aged 1 month to 14 years from discrete administrative areas since 2006 were identified. Each site-time period was matched to a model estimated community-based age-corrected parasite prevalence to provide predictions of prevalence in childhood (PfPR2-10). Admission with all-cause malaria, severe malaria anaemia (SMA), respiratory distress (RD) and cerebral malaria (CM) were analysed as means and predicted probabilities from Bayesian generalised mixed models. RESULTS: 52,684 malaria admissions aged 1 month to 14 years were described at 21 hospitals from 49 site-time locations where PfPR2-10 varied from < 1 to 48.7%. Twelve site-time periods were described as low transmission (PfPR2-10 < 5%), five low-moderate transmission (PfPR2-10 5-9%), 20 moderate transmission (PfPR2-10 10-29%) and 12 high transmission (PfPR2-10 ≥ 30%). The majority of malaria admissions were below 5 years of age (69-85%) and rare among children aged 10-14 years (0.7-5.4%) across all transmission settings. The mean age of all-cause malaria hospitalisation was 49.5 months (95% CI 45.1, 55.4) under low transmission compared with 34.1 months (95% CI 30.4, 38.3) at high transmission, with similar trends for each severe malaria phenotype. CM presented among older children at a mean of 48.7 months compared with 39.0 months and 33.7 months for SMA and RD, respectively. In moderate and high transmission settings, 34% and 42% of the children were aged between 2 and 23 months and so within the age range targeted by chemoprevention or vaccines. CONCLUSIONS: Targeting chemoprevention or vaccination programmes to areas where community-based parasite prevalence is ≥10% is likely to match the age ranges covered by interventions (e.g. intermittent presumptive treatment in infancy to children aged 2-23 months and current vaccine age eligibility and duration of efficacy) and the age ranges of highest disease burden.


Assuntos
Malária Cerebral , Malária Falciparum , Adolescente , África Oriental/epidemiologia , Teorema de Bayes , Criança , Pré-Escolar , Hospitalização , Humanos , Lactente , Malária Cerebral/epidemiologia , Malária Falciparum/epidemiologia , Fenótipo
3.
Crit Care Med ; 48(9): e734-e743, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32618701

RESUMO

OBJECTIVES: Evaluate the relationship between endothelial activation, malaria complications, and long-term cognitive outcomes in severe malaria survivors. DESIGN: Prospectively cohort study of children with cerebral malaria, severe malarial anemia, or community children. SETTING: Mulago National Referral Hospital in Kampala, Uganda. SUBJECTS: Children 18 months to 12 years old with severe malaria (cerebral malaria, n = 253 or severe malarial anemia, n = 211) or community children (n = 206) were followed for 24 months. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Children underwent neurocognitive evaluation at enrollment (community children) or a week following hospital discharge (severe malaria) and 6, 12, and 24 months follow-up. Endothelial activation was assessed at admission on plasma samples (von Willebrand factor, angiopoietin-1 and angiopoietin-2, soluble intercellular adhesion molecule-1, soluble vascular cell adhesion molecule-1, soluble E-Selectin, and P-Selectin). False discovery rate was used to adjust for multiple comparisons. Severe malaria was associated with widespread endothelial activation compared with community children (p < 0.0001 for all markers). Acute kidney injury was independently associated with changes in von Willebrand factor, soluble intercellular adhesion molecule-1, soluble E-Selectin, P-Selectin, and angiopoietin-2 (p < 0.0001 for all). A log10 increase in angiopoietin-2 was associated with lower cognitive z scores across age groups (children < 5, ß -0.42, 95% CI, -0.69 to -0.15, p = 0.002; children ≥ 5, ß -0.39, 95% CI, -0.67 to -0.11, p = 0.007) independent of disease severity (coma, number of seizures, acute kidney injury) and sociodemographic factors. Angiopoietin-2 was associated with hemolysis (lactate dehydrogenase, total bilirubin) and inflammation (tumor necrosis factor-α, interleukin-10). In children with cerebral malaria who had a lumbar puncture performed, angiopoietin-2 was associated with blood-brain barrier dysfunction, and markers of neuroinflammation and injury in the cerebrospinal fluid (tumor necrosis factor-α, kynurenic acid, tau). CONCLUSIONS: These data support angiopoietin-2 as a measure of disease severity and a risk factor for long-term cognitive injury in children with severe malaria.


Assuntos
Injúria Renal Aguda/etiologia , Angiopoietina-2/biossíntese , Disfunção Cognitiva/etiologia , Endotélio/metabolismo , Malária Cerebral/complicações , Injúria Renal Aguda/fisiopatologia , Fatores Etários , Anemia Falciforme/epidemiologia , Criança , Pré-Escolar , Disfunção Cognitiva/fisiopatologia , Comorbidade , Feminino , Hemólise/fisiologia , Humanos , Imunoensaio , Lactente , Mediadores da Inflamação/metabolismo , Malária Cerebral/epidemiologia , Malária Cerebral/fisiopatologia , Masculino , Fatores de Risco , Índice de Gravidade de Doença , Fatores Socioeconômicos , Sobreviventes , Uganda/epidemiologia
4.
BMC Infect Dis ; 20(1): 442, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32576141

RESUMO

BACKGROUND: Cerebral malaria is the most severe form of infection with Plasmodium falciparum characterized by a highly inflammatory response. This systematic review aimed to investigate the association between TNF-α levels and cerebral malaria. METHODS: This review followed the Preferred Reporting of Systematic Review and Meta-analyses (PRISMA) guidelines. The search was performed at PubMed, LILACS, Scopus, Web of Science, The Cochrane Library, OpenGrey and Google Scholar. We have included studies of P. falciparum-infected humans with or without cerebral malaria and TNF-α dosage level. All studies were evaluated using a risk of bias tool and the GRADE approach. RESULTS: Our results have identified 2338 studies, and 8 articles were eligible according to this systematic review inclusion criteria. Among the eight articles, five have evaluated TNF- α plasma dosage, while two have evaluated at the blood and one at the brain (post-Morten). Among them, only five studies showed higher TNF-α levels in the cerebral malaria group compared to the severe malaria group. Methodological problems were identified regarding sample size, randomization and blindness, but no risk of bias was detected. CONCLUSION: Although the results suggested that that TNF-α level is associated with cerebral malaria, the evidence is inconsistent and imprecise. More observational studies evaluating the average TNF-alpha are needed.


Assuntos
Malária Cerebral/epidemiologia , Malária Falciparum/epidemiologia , Fator de Necrose Tumoral alfa/sangue , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Malária Cerebral/sangue , Malária Falciparum/sangue , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum , Adulto Jovem
5.
Nat Rev Neurol ; 16(6): 333-345, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32427939

RESUMO

Zoonotic and vector-borne parasites are important preventable risk factors for epilepsy. Three parasitic infections - cerebral malaria, Taenia solium cysticercosis and onchocerciasis - have an established association with epilepsy. Parasitoses are widely prevalent in low-income and middle-income countries, which are home to 80% of the people with epilepsy in the world. Once a parasitic infection has taken hold in the brain, therapeutic measures do not seem to influence the development of epilepsy in the long term. Consequently, strategies to control, eliminate and eradicate parasites represent the most feasible way to reduce the epilepsy burden at present. The elucidation of immune mechanisms underpinning the parasitic infections, some of which are parasite-specific, opens up new therapeutic possibilities. In this Review, we explore the pathophysiological basis of the link between parasitic infections and epilepsy, and we consider preventive and therapeutic approaches to reduce the burden of epilepsy attributable to parasitic disorders. We conclude that a concerted approach involving medical, veterinary, parasitological and ecological experts, backed by robust political support and sustainable funding, is the key to reducing this burden.


Assuntos
Países em Desenvolvimento/economia , Epilepsia/economia , Doenças Parasitárias/economia , Pobreza/economia , Doenças Transmitidas por Vetores/economia , Zoonoses/economia , Animais , Cisticercose/economia , Cisticercose/epidemiologia , Epilepsia/epidemiologia , Humanos , Malária Cerebral/economia , Malária Cerebral/epidemiologia , Neurocisticercose/economia , Neurocisticercose/epidemiologia , Oncocercose/economia , Oncocercose/epidemiologia , Parasitos , Doenças Parasitárias/epidemiologia , Pobreza/tendências , Doenças Transmitidas por Vetores/epidemiologia , Zoonoses/epidemiologia
6.
Pediatr Infect Dis J ; 38(8): 840-848, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31232898

RESUMO

BACKGROUND: We explored 3 immunopathogenic biomarkers collected during acute malaria illness as potential moderators of gains from a computerized cognitive rehabilitation training (CCRT) intervention. METHOD: Von Willebrand Factor (vWF), tumor necrosis factor (TNF) and Regulated on Activation, Normal T Expressed and Secreted (RANTES) were assayed from plasma and cerebral spinal fluid (CSF) of children during acute severe malaria anemia or cerebral malaria. Two years after acute malaria illness, 150 surviving children and 150 nonmalaria community controls (CCs) from their households 6-12 years old entered a 3-arm randomized controlled trial of titrating and nontitrating CCRT against no CCRT. Tests of cognition [Kaufman Assessment Battery for Children (KABC)], Tests of Variables of Attention and Achenbach Child Behavior Checklist (CBCL) were administered before and after 24 CCRT sessions over a 3-month period, and at 1-year follow-up. Differences in outcomes by trial arms and biomarker levels were evaluated using linear mixed effects models. RESULTS: Severe malaria survivors with lower levels of vWF, lower CSF levels of TNF and higher levels of plasma and CSF RANTES had better KABC cognitive performance after both titrating and nontitrating CCRT compared with no CCRT. For the CBCL, high plasma RANTES was associated with no benefit from either the titrating and nontitrating CCRT, whereas high TNF plasma was predictive of the benefit for both interventions. These biomarker moderating effects were not evident for CC children. CONCLUSIONS: Severe malaria immunopathogenic biomarkers may be related to poorer long-term brain/behavior function as evidenced by diminished benefit from a computerized cognitive rehabilitation intervention.


Assuntos
Biomarcadores , Terapia Cognitivo-Comportamental , Malária Cerebral/epidemiologia , Malária Cerebral/metabolismo , Transtornos Neurocognitivos/epidemiologia , Transtornos Neurocognitivos/etiologia , Atenção , Criança , Comportamento Infantil , Pré-Escolar , Terapia Cognitivo-Comportamental/métodos , Feminino , Humanos , Imunoensaio , Malária Cerebral/complicações , Malária Cerebral/etiologia , Masculino , Transtornos Neurocognitivos/psicologia , Transtornos Neurocognitivos/reabilitação , Testes Neuropsicológicos , Avaliação de Resultados da Assistência ao Paciente , Uganda/epidemiologia , Jogos de Vídeo
7.
Infect Genet Evol ; 69: 107-116, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30677532

RESUMO

Host genetic factors are frequently ascribed to differential malaria outcomes as a by-product of evolutionary adaptation. To this respect, Tumor Necrosis factor alpha (TNF-α), a human cytokine, is known to be associated with malaria through its differential regulation in diverse malaria manifestations. Since diversity in differential malaria outcome is uncommon in every endemic settings, possible association of TNF-α and malaria is not commonly established. In order to check for association between the occurrence of Single Nucleotide Polymorphisms (SNPs) in the TNF-α gene with different malaria manifestations, we have sequenced a 4011 bp region constituting the promoter and the whole gene of human TNF-α in 61 patients [(16 cerebral plus severe (SCM), 21 severe (SM) and 24 uncomplicated (UM)] samples in a highly malaria endemic state (Odisha) of India. Multiple sequence alignment revealed presence of six SNPs (-1031 T > C, -863C > A, -857C > T, -308G > A, -806C > T, +787C > A), out of which the -806C > T and +787C > A are novel in malaria patients in general and the +787C > A was detected for the first time in humans. Although alleles due to six different SNPs segregate differentially in the three groups of malaria (SCM, SM and UM) in the present study, interestingly, for the -1031 T > C position, the frequency of individuals possessing the homozygous rare allele was higher in the SCM group with a higher number of heterozygotes in the UM group. The Tajima's D values considering all the SNPs in a defined group were positive and statistically insignificant conforming no evolutionary constraint. However, statistically significant deviation from expectation under Hardy-Weinberg equilibrium for -1031 T > C SNP in the UM group points towards the probable role of natural selection providing some kind of protection to malaria in Odisha, India.


Assuntos
Evolução Molecular , Predisposição Genética para Doença , Malária/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Fator de Necrose Tumoral alfa/genética , Alelos , Feminino , Ligação Genética , Haplótipos , Humanos , Índia/epidemiologia , Desequilíbrio de Ligação , Malária/epidemiologia , Malária/parasitologia , Malária Cerebral/epidemiologia , Malária Cerebral/genética , Malária Cerebral/parasitologia , Masculino , Morbidade , Avaliação de Resultados da Assistência ao Paciente
8.
Parasite Immunol ; 39(7)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28453871

RESUMO

Systemic tumour necrosis factor-α (TNF-α) may contribute to the pathogenesis of cerebral malaria (CM) by promoting endothelial activation and parasite sequestration. However, less is known about the role of central nervous system (CNS) TNF-α in CM. We assessed plasma (n=249) and cerebrospinal fluid (CSF) (n=167) TNF-α levels in Ugandan children with CM, plasma TNF-α in Ugandan community control children (n=198) and CSF TNF-α in North American control children who had recovered from leukaemia (n=13). Plasma and CSF TNF-α were measured by magnetic bead assay. We compared plasma and CSF TNF-α levels in children with CM to mortality, acute and chronic neurologic deficits and long-term neurocognitive impairment. Plasma and CSF TNF-α levels were higher in CM than control children (P<.0001 for both). CSF TNF-α levels were higher in children who had neurologic deficits at discharge or 6-month follow-up (P≤.05 for both). Elevated CSF but not plasma TNF-α was associated with longer coma duration (Spearman's rho .18, P=.02) and deficits in overall cognition in children 5 years and older (ß coefficient -.74, 95% CI -1.35 to -0.13, P=.02). The study findings suggest that CNS TNF-α may be involved in the development of acute and chronic neurologic and cognitive sequelae in children with CM.


Assuntos
Transtornos Cognitivos/etiologia , Malária Cerebral/complicações , Transtornos Neurocognitivos/etiologia , Plasmodium falciparum/imunologia , Fator de Necrose Tumoral alfa/líquido cefalorraquidiano , Criança , Pré-Escolar , Transtornos Cognitivos/líquido cefalorraquidiano , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/parasitologia , Estudos de Coortes , Feminino , Humanos , Lactente , Malária Cerebral/líquido cefalorraquidiano , Malária Cerebral/epidemiologia , Malária Cerebral/imunologia , Masculino , Transtornos Neurocognitivos/líquido cefalorraquidiano , Transtornos Neurocognitivos/epidemiologia , Transtornos Neurocognitivos/parasitologia , Estudos Prospectivos , Fator de Necrose Tumoral alfa/sangue , Uganda/epidemiologia
9.
J Infect ; 73(3): 189-99, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27311750

RESUMO

OBJECTIVES: Study of the effect of HIV on disease progression in heterogeneous severe malaria syndromes with imprecise diagnostic criteria has led to varying results. Characteristic retinopathy refines cerebral malaria (CM) diagnosis, enabling more precise exploration of the hypothesis that HIV decreases the cytokine response in CM, leading to higher parasite density and a poor outcome. METHODS: We retrospectively reviewed data on clinical progression and laboratory parameters in 877 retinopathy-positive CM cases admitted 1996-2011 (14.4% HIV-infected) to a large hospital in Malawi. Admission plasma levels of TNF, interleukin-10, and soluble intercellular adhesion molecule (sICAM-1) were measured by ELISA in 135 retinopathy-positive CM cases. RESULTS: HIV-infected CM cases had lower median plasma levels of TNF (p = 0.008), interleukin-10 (p = 0.045) and sICAM-1 (p = 0.04) than HIV-uninfected cases. Although HIV-infected children were older and more likely to have co-morbidities, HIV-status did not significantly affect parasite density (p = 0.90) or outcome (24.8% infected, vs. 18.5% uninfected; p = 0.13). CONCLUSION: In this well-characterised CM cohort, HIV-coinfection was associated with marked blunting of the inflammatory response but did not affect parasite density or outcome. These data highlight the complex influence of HIV on severe malaria and bring into question systemic inflammation as a primary driver of pathogenesis in human CM.


Assuntos
Coinfecção/imunologia , Infecções por HIV/complicações , Malária Cerebral/complicações , Malária Cerebral/imunologia , Criança , Pré-Escolar , Progressão da Doença , Feminino , Infecções por HIV/imunologia , Humanos , Lactente , Molécula 1 de Adesão Intercelular/biossíntese , Molécula 1 de Adesão Intercelular/sangue , Interleucina-10/biossíntese , Interleucina-10/sangue , Malária Cerebral/epidemiologia , Malária Cerebral/terapia , Masculino , Estudos Retrospectivos , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/sangue
10.
J Infect Dis ; 212(8): 1322-31, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25883389

RESUMO

Plasmodium falciparum infection can result in severe disease that is associated with elevated inflammation and vital organ dysfunction; however, malaria-endemic residents gain protection from lethal outcomes and manifest only mild symptoms during infection. To characterize host responses associated with this more effective antimalarial response, we characterized whole-blood transcriptional profiles in Rwandan adults during a mild malaria episode and compared them with findings from a convalescence sample. We observed transcriptional up-regulation in many pathways, including type I interferon, interferon γ, complement activation, and nitric oxide during malaria infection, which provide benchmarks of mild disease physiology. Transcripts encoding negative regulators of T-cell activation, such as programmed death ligand 1 (PD-L1), programmed death 1 ligand 2 (PD-L2), and the butyrophilin family member butyrophilin-like 2 (BTNL2) were also increased. To support an important functional role for BTNL2 during malaria infection, we studied chimeric mice reconstituted with BTNL2(-/-) or wild-type hematopoietic cells that were inoculated with Plasmodium berghei ANKA, a murine model of cerebral malaria. We found that BTNL2(-/-) chimeric mice had a significant decrease in survival compared with wild-type counterparts. Collectively these data characterize the immune responses associated with mild malaria and uncover a novel role for BTNL2 in the host response to malaria.


Assuntos
Malária Cerebral/imunologia , Malária Falciparum/imunologia , Glicoproteínas de Membrana/metabolismo , Plasmodium falciparum/imunologia , Adulto , Animais , Antígeno B7-H1/imunologia , Butirofilinas , Ativação do Complemento , Doenças Endêmicas , Feminino , Humanos , Interferon Tipo I/imunologia , Interferon gama/imunologia , Ativação Linfocitária , Malária/epidemiologia , Malária/imunologia , Malária/parasitologia , Malária Cerebral/epidemiologia , Malária Cerebral/parasitologia , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo , Plasmodium berghei/imunologia , Ruanda/epidemiologia , Regulação para Cima , Adulto Jovem
11.
Artigo em Inglês | MEDLINE | ID: mdl-25191643

RESUMO

Pediatric cerebral malaria carries a high mortality rate in sub-Saharan Africa. We present our systematic analysis of the descriptive and quantitative histopathology of all organs sampled from a series of 103 autopsies performed between 1996 and 2010 in Blantyre, Malawi on pediatric cerebral malaria patients and control patients (without coma, or without malaria infection) who were clinically well characterized prior to death. We found brain swelling in all cerebral malaria patients and the majority of controls. The histopathology in patients with sequestration of parasites in the brain demonstrated two patterns: (a) the "classic" appearance (i.e., ring hemorrhages, dense sequestration, and extra-erythrocytic pigment) which was associated with evidence of systemic activation of coagulation and (b) the "sequestration only" appearance associated with shorter duration of illness and higher total burden of parasites in all organs including the spleen. Sequestration of parasites was most intense in the gastrointestinal tract in all parasitemic patients (those with cerebral malarial and those without).


Assuntos
Malária Cerebral/patologia , Autopsia , Encéfalo/patologia , Criança , Pré-Escolar , Glândulas Endócrinas/parasitologia , Glândulas Endócrinas/patologia , Eritrócitos/parasitologia , Eritrócitos/patologia , Trato Gastrointestinal/parasitologia , Trato Gastrointestinal/patologia , Granuloma/patologia , Hemorragia/patologia , Humanos , Lactente , Pulmão/parasitologia , Pulmão/patologia , Malária Cerebral/epidemiologia , Malária Cerebral/parasitologia , Malaui/epidemiologia , Miocárdio/patologia , Sistema Urogenital/parasitologia , Sistema Urogenital/patologia
12.
Lancet Glob Health ; 1(3): e153-60, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24748325

RESUMO

BACKGROUND: Fever with reduced consciousness is an important cause of hospital admission of children in sub-Saharan Africa, with high mortality. Cerebral malaria, diagnosed when acute Plasmodium falciparum infection and coma are recorded with no other apparent reason, is one important cause. We investigated whether viruses could also be an important cause of CNS infection in such patients, and examined the relative contribution of viral pathogens and malaria parasitaemia. METHODS: We did a prospective cohort study in Blantyre, Malawi. From March 1, 2002, to Aug 31, 2004, we enrolled children aged between 2 months and 15 years who were admitted to hospital with suspected non-bacterial CNS infections. Children with a cerebrospinal fluid (CSF) white cell count of less than 1000 cells per µL and negative bacterial microscopy and culture were deemed to have suspected viral CNS infection. Blood was examined for asexual forms of P falciparum. PCR was done on CSF or on post-mortem brain biopsy specimens to detect 15 viruses known to cause CNS infection. FINDINGS: Full outcome data were available for 513 children with suspected viral CNS infection, of whom 94 (18%) died. 163 children (32%) had P falciparum parasitaemia, of whom 34 (21%) died. At least one virus was detected in the CNS in 133 children (26%), of whom 43 (33%) died. 12 different viruses were detected; adenovirus was the most common, affecting 42 children; mumps, human herpes virus 6, rabies, cytomegalovirus, herpes simplex virus 1, and enterovirus were also important. 45 (9%) of the 513 children had both parasitaemia and viral infection, including 27 (35%) of 78 diagnosed clinically with cerebral malaria. Children with dual infection were more likely to have seizures than were those with parasitaemia alone, viral infection only, or neither (p<0·0001). 17 (38%) of the 45 children with dual infection died, compared with 26 (30%) of 88 with viral infection only, 17 (14%) of 118 with parasitaemia only, and 34 (13%) of 262 with neither (p<0·0001). Logistic regression showed children with a viral CNS infection had a significantly higher mortality than did those who did not have a viral CNS infection (p=0·001). INTERPRETATION: Viral CNS infections are an important cause of hospital admission and death in children in Malawi, including in children whose coma might be attributed solely to cerebral malaria. Interaction between viral infection and parasitaemia could increase disease severity. FUNDING: Wellcome Trust, US National Institutes of Health, and UK Medical Research Council.


Assuntos
Viroses do Sistema Nervoso Central/epidemiologia , Doenças Endêmicas , Malária Cerebral/epidemiologia , Malária Falciparum/epidemiologia , Plasmodium falciparum/isolamento & purificação , Adolescente , Viroses do Sistema Nervoso Central/líquido cefalorraquidiano , Criança , Pré-Escolar , Estudos de Coortes , Coinfecção/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Humanos , Lactente , Malária Cerebral/sangue , Malária Cerebral/líquido cefalorraquidiano , Malária Falciparum/sangue , Malária Falciparum/líquido cefalorraquidiano , Malaui/epidemiologia , Masculino , Plasmodium falciparum/genética , Reação em Cadeia da Polimerase , Estudos Prospectivos
13.
Am J Trop Med Hyg ; 80(4): 541-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19346372

RESUMO

Damage to the cerebral microvasculature is a feature of cerebral malaria. Circulating endothelial progenitor cells are needed for microvascular repair. Based on this knowledge, we hypothesized that the failure to mobilize sufficient circulating endothelial progenitor cells to the cerebral microvasculature is a pathophysiologic feature of cerebral malaria. To test this hypothesis, we compared peripheral blood levels of CD34 (+)/VEGFR2(+) and CD34 (+)/CD133(+) cells and plasma levels of the chemokine stromal cell-derived growth factor 1 (SDF-1) in 214 children in Accra, Ghana. Children with cerebral malaria had lower levels of CD34 (+)/VEGFR2(+) and CD34 (+)/CD133(+) cells compared with those with uncomplicated malaria, asymptomatic parasitemia, or healthy controls. SDF-1 levels were higher in children with acute malaria compared with healthy controls. Together, these results uncover a potentially novel role for endothelial progenitor cell mobilization in the pathophysiology of cerebral malaria.


Assuntos
Células Endoteliais/citologia , Malária Cerebral/patologia , Células-Tronco/citologia , Antígeno AC133 , Antígenos CD/análise , Antígenos CD34/análise , Quimiocinas/genética , Quimiocinas/metabolismo , Criança , Pré-Escolar , Células Endoteliais/química , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica , Gana/epidemiologia , Glicoproteínas/análise , Humanos , Lactente , Malária Cerebral/epidemiologia , Masculino , Peptídeos/análise , Células-Tronco/química , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise
14.
Acta Trop ; 102(1): 20-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17397790

RESUMO

Plasma levels of three soluble inducible adhesion molecules, namely: intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1) and endothelial leucocyte adhesion molecule-1 (sELAM-1) or sE-selectin and the pro-inflammatory cytokine, tumour necrosis factor-alpha (TNF-alpha) were measured in well-defined clinical groups of children with severe and uncomplicated malaria. The goal of the study was to investigate the role of these molecules in immunopathogenic processes associated with severe malaria in Cameroonian children. Results showed significantly increased plasma concentrations of sICAM-1, sVCAM-1 and sE-selectin in children with severe malaria compared to those with uncomplicated malaria and healthy children (P<0.001). TNF-alpha levels increased significantly in children with severe malaria, approximately 2-folds compared to those with uncomplicated malaria and about 3-folds compared to healthy children (P<0.001). More importantly, levels of TNF-alpha strongly correlated with those of the three adhesion molecules and were significantly associated with increased risk of death (P=0.03). In addition, children who died from severe malaria showed higher mean levels of all measured factors compared to those who recovered, with significant differences observed with sICAM-1 (P<0.001) and sE-selectin (P=0.002). Furthermore, children with severe malarial anemia relative to those without, showed significantly elevated levels of the three soluble molecules; and sICAM-1 was significantly associated with increased risk of severe anemia. Taken together, these results confirm the role of TNF-alpha and the three adhesion molecules in pathogenic processes associated with severe malaria in children, and suggest an association between sICAM-1 and severe malarial anemia.


Assuntos
Moléculas de Adesão Celular/sangue , Malária Falciparum/imunologia , Malária Falciparum/fisiopatologia , Plasmodium falciparum/patogenicidade , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/sangue , Animais , Camarões/epidemiologia , Criança , Pré-Escolar , Selectina E/sangue , Feminino , Humanos , Lactente , Molécula 1 de Adesão Intercelular/sangue , Malária Cerebral/epidemiologia , Malária Cerebral/imunologia , Malária Cerebral/parasitologia , Malária Cerebral/fisiopatologia , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Masculino , Plasmodium falciparum/isolamento & purificação , Solubilidade , Regulação para Cima , Molécula 1 de Adesão de Célula Vascular/sangue
15.
Rev Neurol ; 43 Suppl 1: S101-9, 2006 Oct 10.
Artigo em Espanhol | MEDLINE | ID: mdl-17061176

RESUMO

INTRODUCTION: The causes of child morbidity in Africa, which are extremely varied, raise a series of aetiopathogenic questions related to socio economics, socio-politics culture, religion and medicine. Development and conclusions. The paper analyses the morbid particularities of malaria in African children, in which numerous (often poorly understood) neurological manifestations are predominant. We also deal with the role played by arterial cerebrovascular malformations, above all in vascular obliterations due to congenital anomalies of haemoglobin or caused by clots formed by the accumulation of Plasmodium falciparum. Apart from malaria, paediatric mortality in Africa, which is made worse by the absence of an equitable form of medicine, is not only due to insufficient involvement by the State but, above all, to the increase in the appearance of orphan pathologies. The most important examples of such conditions are inborn malformations of the cerebrospinal system, traumatic brain or spine injuries and brain tumours. Paediatric neuroAIDS has recently appeared as a new problem to be added to the common infectious pathologies that are a frequent source of neurological complications in African children.


Assuntos
Doenças do Sistema Nervoso/etiologia , Adolescente , África/epidemiologia , Camarões/epidemiologia , Criança , Pré-Escolar , Feminino , Hemoglobina Falciforme , Humanos , Lactente , Recém-Nascido , Malária Cerebral/sangue , Malária Cerebral/epidemiologia , Malária Cerebral/etiologia , Masculino , Doenças do Sistema Nervoso/epidemiologia
16.
J Infect Dis ; 194(6): 837-45, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16941352

RESUMO

BACKGROUND: In children with cerebral malaria (CM), serum chemokine levels and associated morbidity and mortality have not been characterized. METHODS: Serum levels of the cytokines interleukin (IL)-1 beta , IL-6, IL-10, interferon (IFN)-gamma, and tumor necrosis factor-alpha and the chemokines macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta, and regulated upon activation, normal T cell expressed and secreted (RANTES) were measured in Ugandan children with CM, in children with uncomplicated malaria (UM), and in healthy children from the community, as control subjects (CCs). RESULTS: Children with CM had lower levels of RANTES and higher levels of all other cytokines and chemokines than CCs (all P<.0001), and they had lower levels of RANTES (P=.004) and higher levels of IL-10 (P=.003), IFN-gamma (P=.007), and IL-1 beta (P=.05) than children with UM. Children with CM who died had lower levels of RANTES (P=.006) and higher of levels of IL-6 (P=.006), IL-10 (P=.01), IFN-gamma (P=.03), and MIP-1 beta (P=.008) than children who survived. After adjustment for other cytokine and chemokine levels, only low levels of RANTES were independently associated with mortality (P=.016). Levels of RANTES correlated with platelet count but were associated with mortality independently of platelet count. CONCLUSIONS: The serum cytokine and chemokine profile of children who die of CM is similar to that of individuals who die of sepsis. Levels of RANTES are significantly lower in children with CM, and very low levels of RANTES are associated with mortality, independently of other cytokine and chemokine levels.


Assuntos
Quimiocina CCL5/imunologia , Citocinas/sangue , Malária Cerebral/imunologia , Malária Cerebral/mortalidade , Malária Falciparum/imunologia , Quimiocina CCL5/sangue , Criança , Pré-Escolar , Citocinas/imunologia , Feminino , Humanos , Malária Cerebral/epidemiologia , Malária Falciparum/epidemiologia , Masculino , Contagem de Plaquetas , Estatística como Assunto , Fatores de Tempo , Uganda/epidemiologia
17.
Epilepsia ; 47(5): 873-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16686652

RESUMO

PURPOSE: Cerebral malaria (CM) is suspected to be a potential cause of epilepsy in tropical areas, but little information is available. The purpose of this study was to evaluate the role of CM in epilepsy among children in Mali. METHODS: An exposed-nonexposed study was performed to identify children who had epilepsy after malaria in the 0- to 15-year age group. The exposure factor was CM defined according to World Health Organization (WHO) criteria, and the nonexposure factor was symptomatic malaria without the characteristics of CM (NCM). All the children underwent a screening questionnaire and were examined by a medical physician. After the screening phase, a specialist in neuropediatrics examined the children suspected to have epilepsy. EEG and computed tomography (CT) scans were performed in some of these patients. RESULTS: In total, 101 subjects who had had CM and 222 who had had NCM were included. Fifty-four children (CM, 34; NCM, 20) were suspected to have epilepsy, and six were confirmed (CM, five; NCM, one). The incidence rate was 17.0 per 1000 person-years in the CM group and 1.8 per 1000 person-year in the NCM group; thus the relative risk (RR) was 9.4 [95% confidence interval (CI), 1.3-80.3; p = 0.02]. After adjustment on age and duration of follow-up, the RR was 14.3 (95% CI, 1.6-132.0; p = 0.01). CONCLUSIONS: The risk of sequelar epilepsy is significantly higher in the CM group compared with the NCM group. A reevaluation of this cohort should be carried out later to search for temporal epilepsy that appeared after age 10 years.


Assuntos
Epilepsia/epidemiologia , Epilepsia/etiologia , Malária Cerebral/complicações , Malária Cerebral/epidemiologia , Fatores Etários , Criança , Pré-Escolar , Doenças Endêmicas/estatística & dados numéricos , Exposição Ambiental , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mali/epidemiologia , Programas de Rastreamento , Prevalência , Fatores de Risco , Clima Tropical
18.
Med Mal Infect ; 35(7-8): 383-9, 2005.
Artigo em Francês | MEDLINE | ID: mdl-15975752

RESUMO

OBJECTIVES: This retrospective study was carried out to determine the prevalence of cerebromeningeal diseases at the Fann Teaching Hospital Infectious Diseases Clinic, in Dakar, and to describe their epidemiological, clinical, and etiological features. PATIENTS AND METHODS: Data was collected for analysis from patients files recorded from January 1, 2001 to December 31, 2003. RESULTS: Four hundred seventy cases were identified (11.4% of total admissions) with a M/F sex ratio of 1.38 and a mean age of 33 years. Eighty-nine patients were infected by HIV and clinical presentations included fever (78%), meningeal syndrome (57.4%), coma (64.9%), convulsions (19%), focal neurological deficits (15.5%), and cranial nerves dysfunction (7.2%). Etiologies presented as cerebral malaria (85 cases), purulent meningitis (51 cases), neuromeningeal cryptococcosis (37 cases), tuberculous meningitis (11 cases), intracranial abscess (10 cases), toxoplasma encephalitis (4 cases), cerebrovascular attack (11 cases), and cerebromeningeal hemorrhages (3 cases). In as many as 248 cases (52.8%) no etiology could be found. The case fatality rate was 44.5% overall (209 deaths) and 68.5% among HIV-infected patients. Neurological sequels were found in 22 survivors (8.8%), consisting in focal neurological deficit (12 cases), deafness (5 cases), diplopia (2 cases), dementia (2 cases), postmeningitic encephalitis (1 case). CONCLUSION: These results show the need to improve our technical capacities in our diagnostic laboratories, the prevention of opportunistic infections in the course of HIV/AIDS infection, and the involvement of various specialists in the management of cerebromeningeal diseases.


Assuntos
Encefalopatias/epidemiologia , Meningite/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Hemorragia Cerebral/epidemiologia , Criança , Pré-Escolar , Coma/epidemiologia , Grupos Diagnósticos Relacionados , Encefalite/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Mortalidade Hospitalar , Hospitais Universitários/estatística & dados numéricos , Humanos , Malária Cerebral/epidemiologia , Masculino , Meningite Criptocócica/epidemiologia , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Estações do Ano , Senegal/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Toxoplasmose Cerebral/epidemiologia , Tuberculose do Sistema Nervoso Central/epidemiologia
19.
J Soc Biol ; 198(3): 187-92, 2004.
Artigo em Francês | MEDLINE | ID: mdl-15662934

RESUMO

Five to six hundred millions of people, throughout the world, suffer from malaria and more than one million die each year as a consequence, in about 20% of the cases, of cerebral malaria, an important complication of Plasmodium falciparum infection (Holding & Snow, 2001). Despite many studies, the physiopathology of these cerebral occurrences is not understood, especially concerning the intricacy and respective roles of the various mechanisms identified: sequestration of parasitized red cells in microvessels, cytokine secretion, changes in the T lymphocyte repertoire, host genetic factors driving sensitivity pathogenic factors from Plasmodium (Mazier et al., 2000).


Assuntos
Células Endoteliais/fisiologia , Endotélio Vascular/fisiopatologia , Malária Cerebral/fisiopatologia , Animais , Apoptose , Adesão Celular , Circulação Cerebrovascular , Citocinas/fisiologia , Citotoxicidade Imunológica , Eritrócitos/parasitologia , Humanos , Subpopulações de Linfócitos/imunologia , Malária Cerebral/epidemiologia , Malária Cerebral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Microcirculação , Modelos Biológicos , Estresse Oxidativo , Plasmodium berghei , Receptores de Quimiocinas/fisiologia
20.
Malar J ; 2: 6, 2003 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-12716455

RESUMO

BACKGROUND: The inflammatory nature of falciparum malaria has been acknowledged since increased circulating levels of tumour necrosis factor (TNF) were first measured, but precisely where the mediators downstream from this prototype inflammatory mediator are generated has not been investigated. Here we report on the cellular distribution, by immunohistochemistry, of migration inhibitory factor (MIF) and inducible nitric oxide synthase (iNOS) in this disease, and in sepsis. METHODS: We stained for MIF and iNOS in tissues collected during 44 paediatric autopsies in Blantyre, Malawi. These comprised 42 acutely ill comatose patients, 32 of whom were diagnosed clinically as cerebral malaria and the other 10 as non-malarial diseases. Another 2 were non-malarial, non-comatose deaths. Other control tissues were from Australian adults. RESULTS: Of the 32 clinically diagnosed cerebral malaria cases, 11 had negligible histological change in the brain, and no or scanty intravascular sequestration of parasitised erythrocytes, another 7 had no histological changes in the brain, but sequestered parasitised erythrocytes were present (usually dense), and the remaining 14 brains showed micro-haemorrhages and intravascular mononuclear cell accumulations, plus sequestered parasitised erythrocytes. The vascular walls of the latter group stained most strongly for iNOS. Vascular wall iNOS staining was usually of low intensity in the second group (7 brains) and was virtually absent from the cerebral vascular walls of 8 of the 10 comatose patients without malaria, and also from control brains. The chest wall was chosen as a typical non-cerebral site encompassing a range of tissues of interest. Here pronounced iNOS staining in vascular wall and skeletal muscle was present in some 50% of the children in all groups, including septic meningitis, irrespective of the degree of staining in cerebral vascular walls. Parasites or malarial pigment were rare to absent in all chest wall sections. While MIF was common in chest wall vessels, usually in association with iNOS, it was absent in brain vessels. CONCLUSIONS: These results agree with the view that clinically diagnosed cerebral malaria in African children is a collection of overlapping syndromes acting through different organ systems, with several mechanisms, not necessarily associated with cerebral vascular inflammation and damage, combining to cause death.


Assuntos
Fatores Inibidores da Migração de Macrófagos/metabolismo , Malária Falciparum/enzimologia , Malária Falciparum/metabolismo , Óxido Nítrico Sintase/metabolismo , Sepse/enzimologia , Sepse/metabolismo , Adulto , África/epidemiologia , Animais , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Fatores Inibidores da Migração de Macrófagos/imunologia , Malária Cerebral/enzimologia , Malária Cerebral/epidemiologia , Malária Cerebral/metabolismo , Malária Falciparum/epidemiologia , Masculino , Óxido Nítrico Sintase Tipo II , Plasmodium falciparum/isolamento & purificação , Telencéfalo/química , Telencéfalo/patologia , Distribuição Tecidual
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