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1.
Malar J ; 17(1): 435, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30477519

RESUMO

BACKGROUND: Cerebral malaria (CM) is often fatal, and severe brain swelling is a predictor of CM-related mortality. CM is characterized by elevated circulating pro-inflammatory cytokines TNF and IFN-γ and anti-inflammatory cytokine IL-10, however whether cytokine levels correlate with brain swelling severity is unknown. This study therefore was conducted to investigate the relationship between cytokine levels and brain swelling severity in children presenting with CM. METHODS: A total of 195 Malawian children presenting with CM were recruited and had the concentrations of plasma cytokines determined and compared to brain swelling severity, determined by MRI examination, and graded as severe, moderate, mild or none. RESULTS: Levels of IL-1ß, IL-6, IL-8 and IL-10 did not differ between CM patients with and without severe brain swelling. Compared to children without brain swelling, IL-12 levels were higher in children with severe swelling (p < 0.01, no swelling 1 pg/mL, IQR [1] vs. severe swelling 18.7 pg/mL, IQR [1-27]), whereas TNF concentrations were higher in children with moderate brain swelling compared to children with no swelling (p < 0.01, no swelling 3 pg/mL, IQR [1-20] vs. moderate swelling 24 pg/mL, IQR [8-58]. Multivariate analysis showed that no single cytokine independently predicted brain swelling. CONCLUSION: Severe brain swelling in paediatric CM was independent of tested blood pro-inflammatory and anti-inflammatory cytokines which are markers of systemic inflammation.


Assuntos
Edema Encefálico/patologia , Citocinas/sangue , Malária Cerebral/patologia , Plasma/química , Edema Encefálico/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Malaui , Masculino , Índice de Gravidade de Doença
2.
J Infect Dis ; 216(5): 545-553, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28931222

RESUMO

Background: Human immunodeficiency virus (HIV) infection is a recognized risk factor for stroke among young populations, but the exact mechanisms are poorly understood. We studied the clinical, radiologic, and histologic features of HIV-related ischemic stroke to gain insight into the disease mechanisms. Methods: We conducted a prospective, in-depth analysis of adult ischemic stroke patients presenting to Queen Elizabeth Central Hospital, Blantyre, Malawi, in 2011. Results: We recruited 64 HIV-infected and 107 HIV-uninfected patients. Those with HIV were significantly younger (P < .001) and less likely to have established vascular risk factors. Patients with HIV were more likely to have large artery disease (21% vs 10%; P < .001). The commonest etiology was HIV-associated vasculopathy (24 [38%]), followed by opportunistic infections (16 [25%]). Sixteen of 64 (25%) had a stroke soon after starting antiretroviral therapy (ART), suggesting an immune reconstitution-like syndrome. In this group, CD4+ T-lymphocyte count was low, despite a significantly lower HIV viral load in those recently started on treatment (P < .001). Conclusions: HIV-associated vasculopathy and opportunistic infections are common causes of HIV-related ischemic stroke. Furthermore, subtypes of HIV-associated vasculopathy may manifest as a result of an immune reconstitution-like syndrome after starting ART. A better understanding of this mechanism may point toward new treatments.


Assuntos
Infecções por HIV/complicações , Acidente Vascular Cerebral/virologia , Vasculite/complicações , Adulto , Idoso , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Estudos de Casos e Controles , Feminino , HIV , Infecções por HIV/tratamento farmacológico , Humanos , Síndrome Inflamatória da Reconstituição Imune/etiologia , Síndrome Inflamatória da Reconstituição Imune/virologia , Malaui , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Vasculite/diagnóstico , Vasculite/virologia , Carga Viral
3.
Malar J ; 13: 276, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25038815

RESUMO

Understanding the mechanisms underlying the pathophysiology of cerebral malaria in patients with Plasmodium falciparum infection is necessary to implement new curative interventions. While autopsy-based studies shed some light on several pathological events that are believed to be crucial in the development of this neurologic syndrome, their investigative potential is limited and has not allowed the identification of causes of death in patients who succumb to it. This can only be achieved by comparing features between patients who die from cerebral malaria and those who survive. In this review, several alternative approaches recently developed to facilitate the comparison of specific parameters between fatal, non-fatal cerebral malaria and uncomplicated malaria patients are described, as well as their limitations. The emergence of neuroimaging as a revolutionary tool in identifying critical structural and functional modifications of the brain during cerebral malaria is discussed and highly promising areas of clinical research using magnetic resonance imaging are highlighted.


Assuntos
Imageamento por Ressonância Magnética , Malária Cerebral/patologia , Malária Falciparum/patologia , Neuroimagem , Adulto , Ásia/epidemiologia , Autopsia , Edema Encefálico/diagnóstico , Edema Encefálico/etiologia , Isquemia Encefálica/etiologia , Isquemia Encefálica/parasitologia , Causas de Morte , Circulação Cerebrovascular , Criança , Coma/etiologia , Coma/fisiopatologia , Países em Desenvolvimento , Progressão da Doença , Doenças Endêmicas , Eritrócitos/parasitologia , Infecções Oculares Parasitárias/complicações , Humanos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Malária Cerebral/etiologia , Malária Cerebral/mortalidade , Malária Cerebral/fisiopatologia , Malária Falciparum/etiologia , Malária Falciparum/mortalidade , Malária Falciparum/fisiopatologia , Malaui/epidemiologia , Microcirculação , Modelos Biológicos , Mudanças Depois da Morte , Tomografia Computadorizada por Raios X
4.
PLoS One ; 19(4): e0294823, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38640099

RESUMO

BACKGROUND: Despite eradication efforts, ~135,000 African children sustained brain injuries as a result of central nervous system (CNS) malaria in 2021. Newer antimalarial medications rapidly clear peripheral parasitemia and improve survival, but mortality remains high with no associated decline in post-malaria neurologic injury. A randomized controlled trial of aggressive antipyretic therapy with acetaminophen and ibuprofen (Fever RCT) for malarial fevers being conducted in Malawi and Zambia began enrollment in 2019. We propose to use neuroimaging in the context of the RCT to further evaluate neuroprotective effects of aggressive antipyretic therapy. METHODS: This observational magnetic resonance imaging (MRI) ancillary study will obtain neuroimaging and neurodevelopmental and behavioral outcomes in children previously enrolled in the Fever RCT at 1- and 12-months post discharge. Analysis will compare the odds of any brain injury between the aggressive antipyretic therapy and usual care groups based upon MRI structural abnormalities. For children unable to undergo imaging without deep sedation, neurodevelopmental and behavioral outcomes will be used to identify brain injury. DISCUSSION: Neuroimaging is a well-established, valid proxy for neurological outcomes after brain injury in pediatric CNS malaria. This MRI ancillary study will add value to the Fever RCT by determining if treatment with aggressive antipyretic therapy is neuroprotective in CNS malaria. It may also help elucidate the underlying mechanism(s) of neuroprotection and expand upon FEVER RCT safety assessments.


Assuntos
Antipiréticos , Lesões Encefálicas , Malária , Humanos , Criança , Antipiréticos/uso terapêutico , Assistência ao Convalescente , Alta do Paciente , Febre/complicações , Febre/tratamento farmacológico , Febre/prevenção & controle , Imageamento por Ressonância Magnética , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Observacionais como Assunto
5.
Pediatr Blood Cancer ; 60(1): 5-11, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23015404

RESUMO

Wilms tumour is a relatively common and curable paediatric tumour. Known challenges to cure in low income countries are late presentation with advanced disease, malnutrition, failure to complete treatment and limited facilities. In this article, management recommendations are given for a low income setting where only the minimal requirements for treatment with curative intent are available (setting 1). These include general management, supportive care, social support and registration of patients. Recommendations specific for Wilms tumour care include diagnostic procedures with emphasis on the role of ultrasonography, preoperative chemotherapy with a reduced dosage for malnourished children and postoperative chemotherapy based on surgical staging.


Assuntos
Neoplasias Renais/terapia , Tumor de Wilms/terapia , Adolescente , Criança , Pré-Escolar , Terapia Combinada , Diagnóstico Diferencial , Humanos , Lactente , Neoplasias Renais/diagnóstico , Neoplasias Renais/patologia , Estadiamento de Neoplasias , Pobreza , Apoio Social , Tumor de Wilms/diagnóstico , Tumor de Wilms/patologia
6.
medRxiv ; 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37986869

RESUMO

Background: Despite eradication efforts, ~135,000 African children sustained brain injuries as a result of central nervous system (CNS) malaria in 2021. Newer antimalarial medications rapidly clear peripheral parasitemia and improve survival, but mortality remains high with no associated decline in post-malaria neurologic injury. A randomized controlled trial of aggressive antipyretic therapy with acetaminophen and ibuprofen (Fever RCT) for malarial fevers being conducted in Malawi and Zambia began enrollment in 2019. We propose to use neuroimaging in the context of the RCT to further evaluate neuroprotective effects of aggressive antipyretic therapy. Methods: This observational magnetic resonance imaging (MRI) ancillary study will obtain neuroimaging and neurodevelopmental and behavioral outcomes in children previously enrolled in the Fever RCT at 1- and 12-months post discharge. Analysis will compare the odds of any brain injury between the aggressive antipyretic therapy and usual care groups based upon MRI structural abnormalities. For children unable to undergo imaging without deep sedation, neurodevelopmental and behavioral outcomes will be used to identify brain injury. Discussion: Neuroimaging is a well-established, valid proxy for neurological outcomes after brain injury in pediatric CNS malaria. This MRI ancillary study will add value to the Fever RCT by determining if treatment with aggressive antipyretic therapy is neuroprotective in CNS malaria. It may also help elucidate the underlying mechanism(s) of neuroprotection and expand upon FEVER RCT safety assessments.

7.
Clin Infect Dis ; 54(8): 1100-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22357702

RESUMO

BACKGROUND: Salmonella enterica serovar Typhi causes an estimated 22 million cases of typhoid fever and 216 000 deaths annually worldwide. We investigated an outbreak of unexplained febrile illnesses with neurologic findings, determined to be typhoid fever, along the Malawi-Mozambique border. METHODS: The investigation included active surveillance, interviews, examinations of ill and convalescent persons, medical chart reviews, and laboratory testing. Classification as a suspected case required fever and ≥1 other finding (eg, headache or abdominal pain); a probable case required fever and a positive rapid immunoglobulin M antibody test for typhoid (TUBEX TF); a confirmed case required isolation of Salmonella Typhi from blood or stool. Isolates underwent antimicrobial susceptibility testing and subtyping by pulsed-field gel electrophoresis (PFGE). RESULTS: We identified 303 cases from 18 villages with onset during March-November 2009; 214 were suspected, 43 were probable, and 46 were confirmed cases. Forty patients presented with focal neurologic abnormalities, including a constellation of upper motor neuron signs (n = 19), ataxia (n = 22), and parkinsonism (n = 8). Eleven patients died. All 42 isolates tested were resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole; 4 were also resistant to nalidixic acid. Thirty-five of 42 isolates were indistinguishable by PFGE. CONCLUSIONS: The unusual neurologic manifestations posed a diagnostic challenge that was resolved through rapid typhoid antibody testing in the field and subsequent blood culture confirmation in the Malawi national reference laboratory. Extending laboratory diagnostic capacity, including blood culture, to populations at risk for typhoid fever in Africa will improve outbreak detection, response, and clinical treatment.


Assuntos
Surtos de Doenças , Farmacorresistência Bacteriana Múltipla , Doenças do Sistema Nervoso/epidemiologia , Salmonella typhi/efeitos dos fármacos , Febre Tifoide/complicações , Febre Tifoide/diagnóstico , Febre Tifoide/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , Eletroforese em Gel de Campo Pulsado , Feminino , Febre/diagnóstico , Febre/etiologia , Humanos , Imunoglobulina M/sangue , Lactente , Malaui/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem Molecular , Moçambique/epidemiologia , Doenças do Sistema Nervoso/etiologia , Salmonella typhi/classificação , Salmonella typhi/genética , Salmonella typhi/isolamento & purificação , Febre Tifoide/microbiologia , Adulto Jovem
8.
Blood Adv ; 4(13): 2851-2864, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32579667

RESUMO

Microvascular thrombosis and blood-brain barrier (BBB) breakdown are key components of cerebral malaria (CM) pathogenesis in African children and are implicated in fatal brain swelling. How Plasmodium falciparum infection causes this endothelial disruption and why this occurs, particularly in the brain, is not fully understood. In this study, we have demonstrated that circulating extracellular histones, equally of host and parasite origin, are significantly elevated in CM patients. Higher histone levels are associated with brain swelling on magnetic resonance imaging. On postmortem brain sections of CM patients, we found that histones are colocalized with P falciparum-infected erythrocytes sequestered inside small blood vessels, suggesting that histones might be expelled locally during parasite schizont rupture. Histone staining on the luminal vascular surface colocalized with thrombosis and leakage, indicating a possible link between endothelial surface accumulation of histones and coagulation activation and BBB breakdown. Supporting this, patient sera or purified P falciparum histones caused disruption of barrier function and were toxic to cultured human brain endothelial cells, which were abrogated with antihistone antibody and nonanticoagulant heparin. Overall, our data support a role for histones of parasite and host origin in thrombosis, BBB breakdown, and brain swelling in CM, processes implicated in the causal pathway to death. Neutralizing histones with agents such as nonanticoagulant heparin warrant exploration to prevent brain swelling in the development or progression of CM and thereby to improve outcomes.


Assuntos
Malária Cerebral , Parasitos , Trombose , Animais , Encéfalo , Criança , Células Endoteliais , Endotélio , Histonas , Humanos , Plasmodium falciparum , Trombose/etiologia
9.
Am J Trop Med Hyg ; 102(2): 451-457, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31837130

RESUMO

Nontraumatic myelopathy causes severe morbidity and is not uncommon in Africa. Clinically, patients often present with paraplegia, and extrinsic cord compression and transverse myelitis are most common causes. Data on exact pathogenesis are scanty because of limitations in diagnostic methods. In Queen Elizabeth Central Hospital, Blantyre, Malawi, we recorded consecutive patients presenting with nontraumatic paraplegia for maximally 6 months between January and July 2010 and from March to December 2011. The diagnostic workup included imaging and examining blood, stool, urine, sputum, and cerebrospinal fluid (CSF) samples for infection. After discharge, additional diagnostic tests, including screening for virus infections, borreliosis, syphilis, and schistosomiasis, were carried out in the Netherlands. The clinical diagnosis was, thus, revised in retrospect with a more accurate final differential diagnosis. Of 58 patients included, the mean age was 41 years (range, 12-83 years) and the median time between onset and presentation was 18 days (range, 0-121 days), and of 55 patients tested, 23 (42%) were HIV positive. Spinal tuberculosis (n = 24, 41%), tumors (n = 16, 28%), and transverse myelitis (n = 6, 10%) were most common; in six cases (10%), no diagnosis could be made. The additional tests yielded evidence for CSF infection with Schistosoma, Treponema pallidum, Epstein-Barr virus (EBV), HHV-6, HIV, as well as a novel cyclovirus. The diagnosis of the cause of paraplegia is complex and requires access to an magnetic resonance imaging (MRI) scan and other diagnostic (molecular) tools to demonstrate infection. The major challenge is to confirm the role of detected pathogens in the pathophysiology and to design an effective and affordable diagnostic approach.


Assuntos
Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Doenças da Medula Espinal/epidemiologia , Doenças da Medula Espinal/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Anticorpos Anti-HIV/sangue , Humanos , Malaui/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Adulto Jovem
10.
Pediatrics ; 143(2)2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30696757

RESUMO

: media-1vid110.1542/5972295739001PEDS-VA_2018-1026Video Abstract BACKGROUND AND OBJECTIVES: Cerebral malaria (CM) causes significant mortality and morbidity in sub-Saharan African children. Reliable morbidity estimates are scarce because of methodological variability across studies. We describe the incidence, course, and severity of neurodevelopmental impairments in survivors of CM and the associated patient characteristics to inform epidemiologic estimates of malaria morbidity rates and prevention and treatment efforts. METHODS: We conducted an exposure-control study of 85 survivors of CM and 100 age-matched patients in a control group who were enrolled at hospital discharge and assessed after 1, 6, and 12 months using caregiver interviews and standardized developmental, cognitive, and behavioral measures. RESULTS: Developmental or cognitive impairment (<10th percentile of the control distribution) and/or new onset of caregiver-reported behavior problems occurred in 53% of case patients compared with 20% of the patients in the control group (odds ratio 4.5; 95% CI: 2.4 to 8.6; P < .001). In case patients, developmental or cognitive impairment at the 12-month assessment was associated with HIV-positive status and short stature at presentation, more prolonged fever and coma during admission, and severe atrophy or multifocal abnormalities being found on MRI at the 1-month assessment. CONCLUSIONS: One-half of survivors of CM were neurodevelopmentally impaired at the 1-year assessment. With these results, we support prevention trials of acute, neuroprotective interventions and the allocation of resources to evaluation, education, and rehabilitation efforts to reduce the significant long-term burden of CM-associated impairments on families and their communities.


Assuntos
Malária Cerebral/diagnóstico por imagem , Malária Cerebral/epidemiologia , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Transtornos do Neurodesenvolvimento/epidemiologia , Pré-Escolar , Feminino , Seguimentos , Humanos , Malária Cerebral/psicologia , Malaui/epidemiologia , Masculino , Transtornos do Neurodesenvolvimento/psicologia , Fatores de Tempo
11.
Trop Med Int Health ; 13(11): 1400-4, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18983275

RESUMO

OBJECTIVE: To evaluate optic nerve sheath (ONS) ultrasound as a non-invasive method of detecting raised intracranial pressure (ICP) and to establish normal ONS diameter data for African children. METHOD: Children with acute neurological disease admitted to the Paediatric Department of Queen Elizabeth Central Hospital, Malawi had ultrasound measurements of ONS diameter. Controls were children admitted to the same department with non-neurological disease. The mean of three measurements of the ONS diameter was used for analysis. Children were assessed for clinical signs of raised ICP. Patients had CT brain scans if required for their normal clinical care. RESULTS: In 14 children with neurological disease and clinical signs suggestive of raised ICP, the mean ONS diameter was 5.4 mm (range 4.3-6.2 mm). Radiological signs on CT scans substantiated the presence of raised ICP in eight (all those scanned). In seven children with neurological disease but no specific signs of raised ICP the mean ONS diameter was 3.6 mm (range 2.8-4.4 mm). None of four of these patients examined by CT scan had signs of elevated ICP. The mean ONS diameter in 30 controls without neurological disease was 3.5 mm (range 2.5-4.1 mm). If 4.2 mm is taken as the upper limit of normal the sensitivity and specificity of this test for elevated ICP is 100% and 86%, respectively. CONCLUSION: ONS ultrasound is an accurate method for detecting raised ICP that can be applied in a broad range of settings. It has the advantages of being a non-invasive, bedside test, which can be repeated multiple times for re-evaluation.


Assuntos
Hipertensão Intracraniana/diagnóstico por imagem , Bainha de Mielina/diagnóstico por imagem , Doenças do Sistema Nervoso/diagnóstico por imagem , Nervo Óptico/diagnóstico por imagem , Distribuição por Idade , Estudos de Casos e Controles , Pré-Escolar , Feminino , Humanos , Lactente , Malaui , Masculino , Doenças do Sistema Nervoso/fisiopatologia , Sistemas Automatizados de Assistência Junto ao Leito , Estudos Prospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia
12.
Am J Trop Med Hyg ; 97(1): 225-231, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28719298

RESUMO

Cerebral malaria (CM) is a common cause of death and disability among children in sub-Saharan Africa. Many prior studies of neuropsychiatric morbidity have been limited by a cross-sectional design or a short duration of follow-up. Most have included subjects who may have presented with coma due to a disease process other than CM. No studies have assessed the relationship between magnetic resonance imaging (MRI) findings and long-term outcomes. The Cognitive Outcomes and Psychiatric symptoms of retinopathy-positive CM (COPS) cohort is the first large (N = 221) prospectively recruited cohort of stringently defined cases of CM and hospital-based, age-matched, non-CM controls in whom cognitive and psychiatric outcomes are assessed with standardized measures semi-annually for up to 5 years. We report baseline characteristics of the cohort and outcomes at 1 month. At enrollment, CM cases were more likely to come from families with fewer socioeconomic resources and to have health characteristics that increase risk for malaria. In children younger than 5 years, cases were delayed in motor, language, and social development by approximately 6 months, compared with controls. More significant delays occurred in those with MRI abnormalities at the 1-month follow-up visit. There were no differences between cases and controls in inhibitory self-control, nor in cognitive function in children ≥ 5 years of age. The latter finding may be related to the smaller sample size, case-control imbalance in socioeconomic status, or the use of cognitive and behavioral assessments that are less culturally appropriate to this population. Continued follow-up will help determine predictors of long-term outcomes.


Assuntos
Disfunção Cognitiva/etiologia , Malária Cerebral/complicações , Doenças Retinianas/etiologia , Estudos de Casos e Controles , Criança , Desenvolvimento Infantil , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Doenças Retinianas/parasitologia
13.
mSphere ; 2(3)2017.
Artigo em Inglês | MEDLINE | ID: mdl-28596990

RESUMO

The mechanisms underlying the rapidly reversible brain swelling described in patients with cerebral malaria (CM) are unknown. Using a 1.5-Tesla (T) magnetic resonance imaging (MRI) scanner, we undertook an observational study in Rourkela, India, of 11 Indian patients hospitalized with CM and increased brain volume. Among the 11 cases, there were 5 adults and 6 children. All patients had reduced consciousness and various degrees of cortical swelling at baseline. The latter was predominately posterior in distribution. The findings on diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps were consistent with vasogenic edema in all cases. Reversibility after 48 to 72 h was observed in >90% of cases. DWI/ADC mismatch suggested the additional presence of cytotoxic edema in the basal nuclei of 5 patients; all of these had perfusion parameters consistent with vascular engorgement and not with ischemic infarcts. Our results suggest that an impairment of the blood-brain barrier is responsible for the brain swelling in CM. In 5 cases, vasogenic edema occurred in conjunction with changes in the basal nuclei consistent with venous congestion, likely to be caused by the sequestration of Plasmodium falciparum-infected erythrocytes. While both mechanisms have been individually postulated to play an important role in the development of CM, this is the first demonstration of their concurrent involvement in different parts of the brain. The clinical and radiological characteristics observed in the majority of our patients are consistent with posterior reversible encephalopathy syndrome (PRES), and we show for the first time a high frequency of PRES in the context of CM. IMPORTANCE The pathophysiology and molecular mechanisms underlying cerebral malaria (CM) are still poorly understood. Recent neuroimaging studies demonstrated that brain swelling is a common feature in CM and a major contributor to death in pediatric patients. Consequently, determining the precise mechanisms responsible for this swelling could open new adjunct therapeutic avenues in CM patients. Using an MRI scanner with a higher resolution than the ones used in previous reports, we identified two distinct origins of brain swelling in both adult and pediatric patients from India, occurring in distinct parts of the brain. Our results support the hypothesis that both endothelial dysfunction and microvascular obstruction by Plasmodium falciparum-infected erythrocytes make independent contributions to the pathogenesis of CM, providing opportunities for novel therapeutic interventions.

14.
Cell Host Microbe ; 22(5): 601-614.e5, 2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-29107642

RESUMO

Brain swelling is a major predictor of mortality in pediatric cerebral malaria (CM). However, the mechanisms leading to swelling remain poorly defined. Here, we combined neuroimaging, parasite transcript profiling, and laboratory blood profiles to develop machine-learning models of malarial retinopathy and brain swelling. We found that parasite var transcripts encoding endothelial protein C receptor (EPCR)-binding domains, in combination with high parasite biomass and low platelet levels, are strong indicators of CM cases with malarial retinopathy. Swelling cases presented low platelet levels and increased transcript abundance of parasite PfEMP1 DC8 and group A EPCR-binding domains. Remarkably, the dominant transcript in 50% of swelling cases encoded PfEMP1 group A CIDRα1.7 domains. Furthermore, a recombinant CIDRα1.7 domain from a pediatric CM brain autopsy inhibited the barrier-protective properties of EPCR in human brain endothelial cells in vitro. Together, these findings suggest a detrimental role for EPCR-binding CIDRα1 domains in brain swelling.


Assuntos
Edema Encefálico/metabolismo , Receptor de Proteína C Endotelial/metabolismo , Malária Cerebral/metabolismo , Proteínas de Neoplasias/metabolismo , Plasmodium falciparum/metabolismo , Plasmodium falciparum/patogenicidade , Receptores de Superfície Celular/metabolismo , Encéfalo/parasitologia , Edema Encefálico/parasitologia , Adesão Celular , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Malária Cerebral/parasitologia , Malária Falciparum/metabolismo , Malária Falciparum/parasitologia , Malária Falciparum/fisiopatologia , Malaui , Masculino , Ligação Proteica , Domínios Proteicos , Proteínas de Protozoários/metabolismo
15.
Pediatr Infect Dis J ; 25(6): 566-7, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16732162

RESUMO

Meningococcal disease remains a major cause of morbidity and mortality in childhood. Cerebral infarction complicating meningococcal meningitis is recognized but uncommon. We describe a 3-year-old boy with parieto-occipital infarction secondary to meningococcal meningitis, resulting in permanent visual loss as the sole neurologic sequelae and, consequently, major implications for his subsequent development.


Assuntos
Cegueira Cortical/etiologia , Infarto Cerebral/complicações , Meningite Meningocócica/complicações , Cegueira Cortical/fisiopatologia , Infarto Cerebral/diagnóstico , Infarto Cerebral/terapia , Pré-Escolar , Serviço Hospitalar de Emergência , Seguimentos , Humanos , Masculino , Meningite Meningocócica/diagnóstico , Meningite Meningocócica/tratamento farmacológico , Medição de Risco , Índice de Gravidade de Doença , Punção Espinal
16.
Neurology ; 86(4): 324-33, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26683649

RESUMO

OBJECTIVE: To investigate HIV, its treatment, and hypertension as stroke risk factors in Malawian adults. METHODS: We performed a case-control study of 222 adults with acute stroke, confirmed by MRI in 86%, and 503 population controls, frequency-matched for age, sex, and place of residence, using Global Positioning System for random selection. Multivariate logistic regression models were used for case-control comparisons. RESULTS: HIV infection (population attributable fraction [PAF] 15%) and hypertension (PAF 46%) were strongly linked to stroke. HIV was the predominant risk factor for young stroke (≤45 years), with a prevalence of 67% and an adjusted odds ratio (aOR) (95% confidence interval) of 5.57 (2.43-12.8) (PAF 42%). There was an increased risk of a stroke in patients with untreated HIV infection (aOR 4.48 [2.44-8.24], p < 0.001), but the highest risk was in the first 6 months after starting antiretroviral therapy (ART) (aOR 15.6 [4.21-46.6], p < 0.001); this group had a lower median CD4(+) T-lymphocyte count (92 vs 375 cells/mm(3), p = 0.004). In older participants (HIV prevalence 17%), HIV was associated with stroke, but with a lower PAF than hypertension (5% vs 68%). There was no interaction between HIV and hypertension on stroke risk. CONCLUSIONS: In a population with high HIV prevalence, where stroke incidence is increasing, we have shown that HIV is an important risk factor. Early ART use in immunosuppressed patients poses an additional and potentially treatable stroke risk. Immune reconstitution inflammatory syndrome may be contributing to the disease mechanisms.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Infecções por HIV/epidemiologia , Hipertensão/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Hipertensão/complicações , Síndrome Inflamatória da Reconstituição Imune/complicações , Síndrome Inflamatória da Reconstituição Imune/epidemiologia , Malaui/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/etiologia
17.
Neurology ; 87(22): 2355-2362, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-27794112

RESUMO

OBJECTIVE: We assessed the independent association of lumbar puncture (LP) and death in Malawian children admitted to the hospital with the clinical features of cerebral malaria (CM). METHODS: This was a retrospective cohort study in Malawian children with clinical features of CM. Allocation to LP was nonrandom and was associated with severity of illness. Propensity score-based analyses were used to adjust for this bias and assess the independent association between LP and mortality. RESULTS: Data were available for 1,075 children: 866 (80.6%) underwent LP and 209 (19.4%) did not. Unadjusted mortality rates were lower in children who underwent LP (15.3% vs 26.7% in the no-LP group) but differences in covariates between the 2 groups suggested bias in LP allocation. After propensity score matching, all covariates were balanced. Propensity score-based analyses showed no change in mortality rate associated with LP: by inverse probability weighting, the average risk reduction was 2.0% at 12 hours (95% confidence interval -1.5% to 5.5%, p = 0.27) and 1.7% during hospital admission (95% confidence interval -4.5% to 7.9%, p = 0.60). Undergoing LP did not change the risk of mortality in subanalyses of children with severe brain swelling on MRI or in those with papilledema. CONCLUSION: In comatose children with suspected CM who were clinically stable, we found no evidence that LP increases mortality, even in children with objective signs of raised intracranial pressure.


Assuntos
Malária Cerebral/mortalidade , Punção Espinal/efeitos adversos , Adolescente , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Hospitalização , Humanos , Lactente , Imageamento por Ressonância Magnética , Malária Cerebral/diagnóstico por imagem , Malária Cerebral/fisiopatologia , Malária Cerebral/terapia , Malaui/epidemiologia , Masculino , Papiledema/complicações , Papiledema/mortalidade , Papiledema/fisiopatologia , Papiledema/terapia , Pontuação de Propensão , Estudos Retrospectivos , Risco , Índice de Gravidade de Doença
18.
AIDS ; 16(10): 1409-17, 2002 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-12131218

RESUMO

OBJECTIVE: HIV-infected patients in Africa are vulnerable to severe recurrent infection with Streptococcus pneumoniae, but no effective preventive strategy has been developed. We set out to determine which factors influence in-hospital mortality and long-term survival of Malawians with invasive pneumococcal disease. DESIGN, SETTING AND PATIENTS: Acute clinical features, inpatient mortality and long-term survival were described among consecutively admitted hospital patients with S. pneumoniae in the blood or cerebrospinal fluid. Factors associated with inpatient mortality were determined, and patients surviving to discharge were followed to determine their long-term outcome. RESULTS: A total of 217 patients with pneumococcal disease were studied over an 18-month period. Among these, 158 out of 167 consenting to testing (95%) were HIV positive. Inpatient mortality was 65% for pneumococcal meningitis (n = 64), 20% for pneumococcaemic pneumonia (n = 92), 26% for patients with pneumococcaemia without localizing signs (n = 43), and 76% in patients with probable meningitis (n = 17). Lowered consciousness level, hypotension, and age exceeding 55 years at presentation were associated with inpatient death, but not long-term outcome in survivors. Hospital survivors were followed for a median of 414 days; 39% died in the community during the study period. Outpatient death was associated with multilobar chest signs, oral candidiasis, and severe anaemia as an inpatient. CONCLUSION: Most patients with pneumococcal disease in Malawi have HIV co-infection. They have severe disease with a high mortality rate. At discharge, all HIV-infected adults have a poor prognosis but patients with multilobar chest signs or anaemia are at particular risk.


Assuntos
Infecções por HIV/complicações , Infecções Pneumocócicas/complicações , Streptococcus pneumoniae , Fatores Etários , Anemia/complicações , Candidíase Bucal/complicações , Estudos de Coortes , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/mortalidade , Hospitalização , Humanos , Malaui/epidemiologia , Masculino , Pessoa de Meia-Idade , Infecções Pneumocócicas/microbiologia , Infecções Pneumocócicas/mortalidade , Prognóstico , Fatores de Risco , Streptococcus pneumoniae/isolamento & purificação , Análise de Sobrevida
19.
Am J Trop Med Hyg ; 91(5): 943-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25200262

RESUMO

Our goals were to understand the brain magnetic resonance imaging (MRI) findings in children with retinopathy-negative cerebral malaria (CM) and investigate whether any findings on acute MRI were associated with adverse outcomes. We performed MRI scans on children admitted to the hospital in Blantyre, Malawi with clinically defined CM. Two hundred and seventeen children were imaged during the study period; 44 patients were malarial retinopathy-negative; and 173 patients were retinopathy-positive. We compared MRI findings in children with retinopathy-negative and retinopathy-positive CM. In children who were retinopathy-negative, we identified MRI variables that were associated with death and adverse neurologic outcomes. On multivariate analysis, cortical diffusion weighted imaging (DWI) abnormality and increased brain volume were strongly associated with neurologic morbidity in survivors. Investigations to explore the underlying pathophysiologic processes responsible for these MRI changes are warranted.


Assuntos
Encéfalo/ultraestrutura , Imageamento por Ressonância Magnética , Malária Cerebral/diagnóstico , Doenças Retinianas/diagnóstico , Doenças Retinianas/parasitologia , Pré-Escolar , Feminino , Humanos , Modelos Logísticos , Malária Cerebral/fisiopatologia , Malaui , Masculino , Análise Multivariada , Neuroimagem/métodos , Doenças Retinianas/fisiopatologia
20.
Am J Trop Med Hyg ; 88(3): 542-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23339204

RESUMO

Abstract. A prospective cohort study of retinopathy-confirmed cerebral malaria (CM) survivors identified 42 of 132 with neurologic sequelae. The 38 survivors with sequelae who were alive when magnetic resonance imaging (MRI) technology became available underwent brain MRIs. Common MRI abnormalities included periventricular T2 signal changes (53%), atrophy (47%), subcortical T2 signal changes (18%), and focal cortical defects (16%). The χ(2) tests assessed the relationship between chronic MRI findings, acute clinical and demographic data, and outcomes. Children who were older at the time of CM infection (P = 0.01) and those with isolated behavioral problems (P = 0.02) were more likely to have a normal MRI. Acute focal seizures were associated with atrophy (P = 0.05). Acute papilledema was associated with subcortical T2 signal changes (P = 0.02). Peripheral retinal whitening (P = 0.007) and a higher admission white blood cell count (P = 0.02) were associated with periventricular T2 signal changes. Chronic MRI findings suggest seizures, increased intracranial pressure, and microvascular ischemia contribute to clinically relevant structural brain injury in CM.


Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética , Malária Cerebral/complicações , Envelhecimento , Dano Encefálico Crônico , Criança , Transtornos do Comportamento Infantil , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino
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