RESUMO
BACKGROUND: In cerebral malaria, the retina can be used to understand disease pathogenesis. The mechanisms linking sequestration, brain swelling, and death remain poorly understood. We hypothesized that retinal vascular leakage would be associated with brain swelling. METHODS: We used retinal angiography to study blood-retinal barrier integrity. We analyzed retinal leakage, histopathology, brain magnatic resonance imaging (MRI), and associations with death and neurological disability in prospective cohorts of Malawian children with cerebral malaria. RESULTS: Three types of retinal leakage were seen: large focal leak (LFL), punctate leak (PL), and vessel leak. The LFL and PL were associated with death (odds ratio [OR] = 13.20, 95% confidence interval [CI] = 5.21-33.78 and OR = 8.58, 95% CI = 2.56-29.08, respectively) and brain swelling (Pâ <â .05). Vessel leak and macular nonperfusion were associated with neurological disability (OR = 3.71, 95% CI = 1.26-11.02 and OR = 9.06, 95% CI = 1.79-45.90). Large focal leak was observed as an evolving retinal hemorrhage. A core of fibrinogen and monocytes was found in 39 (93%) white-centered hemorrhages. CONCLUSIONS: Blood-retina barrier breakdown occurs in 3 patterns in cerebral malaria. Associations between LFL, brain swelling, and death suggest that the rapid accumulation of cerebral hemorrhages, with accompanying fluid egress, may cause fatal brain swelling. Vessel leak, from barrier dysfunction, and nonperfusion were not associated with severe brain swelling but with neurological deficits, suggesting hypoxic injury in survivors.
Assuntos
Edema Encefálico , Malária Cerebral , Barreira Hematorretiniana/patologia , Edema Encefálico/complicações , Edema Encefálico/patologia , Criança , Humanos , Malária Cerebral/complicações , Estudos Prospectivos , Retina/patologiaRESUMO
BACKGROUND: Case fatality rates among African children with cerebral malaria remain in the range of 15 to 25%. The key pathogenetic processes and causes of death are unknown, but a combination of clinical observations and pathological findings suggests that increased brain volume leading to raised intracranial pressure may play a role. Magnetic resonance imaging (MRI) became available in Malawi in 2009, and we used it to investigate the role of brain swelling in the pathogenesis of fatal cerebral malaria in African children. METHODS: We enrolled children who met a stringent definition of cerebral malaria (one that included the presence of retinopathy), characterized them in detail clinically, and obtained MRI scans on admission and daily thereafter while coma persisted. RESULTS: Of 348 children admitted with cerebral malaria (as defined by the World Health Organization), 168 met the inclusion criteria, underwent all investigations, and were included in the analysis. A total of 25 children (15%) died, 21 of whom (84%) had evidence of severe brain swelling on MRI at admission. In contrast, evidence of severe brain swelling was seen on MRI in 39 of 143 survivors (27%). Serial MRI scans showed evidence of decreasing brain volume in the survivors who had had brain swelling initially. CONCLUSIONS: Increased brain volume was seen in children who died from cerebral malaria but was uncommon in those who did not die from the disease, a finding that suggests that raised intracranial pressure may contribute to a fatal outcome. The natural history indicates that increased intracranial pressure is transient in survivors. (Funded by the National Institutes of Health and Wellcome Trust U.K.).
Assuntos
Edema Encefálico/etiologia , Malária Cerebral/complicações , Encéfalo/patologia , Edema Encefálico/diagnóstico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Malária Cerebral/mortalidade , Malaui/epidemiologia , Masculino , Tamanho do Órgão , Papiledema/etiologiaRESUMO
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 DoençaRESUMO
BACKGROUND: Cerebral malaria (CM) causes a rapidly developing coma, and remains a major contributor to morbidity and mortality in malaria-endemic regions. This study sought to determine the relationship between cerebrospinal fluid (CSF) Plasmodium falciparum histidine rich protein-2 (PfHRP-2) and clinical, laboratory and radiographic features in a cohort of children with retinopathy-positive CM. METHODS: Patients included in the study were admitted (2009-2013) to the Pediatric Research Ward (Queen Elizabeth Central Hospital, Blantyre, Malawi) meeting World Health Organization criteria for CM with findings of malarial retinopathy. Enzyme-linked immunosorbent assay was used to determine plasma and CSF PfHRP-2 levels. Wilcoxon rank-sum tests and multivariable logistic regression analysis assessed the association of clinical and radiographic characteristics with the primary outcome of death during hospitalization. RESULTS: In this cohort of 94 patients, median age was 44 (interquartile range 29-62) months, 53 (56.4%) patients were male, 6 (7%) were HIV-infected, and 10 (11%) died during hospitalization. Elevated concentrations of plasma lactate (p = 0.005) and CSF PfHRP-2 (p = 0.04) were significantly associated with death. On multivariable analysis, higher PfHRP-2 in the CSF was associated with death (odds ratio 9.00, 95% confidence interval 1.44-56.42) while plasma PfHRP-2 was not (odds ratio 2.05, 95% confidence interval 0.45-9.35). CONCLUSIONS: Elevation of CSF, but not plasma PfHRP-2, is associated with death in this paediatric CM cohort. PfHRP-2 egress into the CSF may represent alteration of blood brain barrier permeability related to the sequestration of parasitized erythrocytes in the cerebral microvasculature.
Assuntos
Antígenos de Protozoários/líquido cefalorraquidiano , Malária Cerebral/líquido cefalorraquidiano , Malária Falciparum/líquido cefalorraquidiano , Proteínas de Protozoários/líquido cefalorraquidiano , Pré-Escolar , Feminino , Humanos , Malária Cerebral/mortalidade , Malária Cerebral/patologia , Malária Falciparum/mortalidade , Malária Falciparum/patologia , Masculino , Plasmodium falciparum , Estudos RetrospectivosRESUMO
BACKGROUND: Recurrent seizure risks in HIV-positive people with new-onset seizure are largely unknown, making it challenging to offer optimal recommendations regarding antiepileptic drug (AED) initiation. Existing outcomes data is limited, and risk factor identification requires a diagnostic assessment, which is often unavailable in regions heavily effected by HIV, like sub-Saharan Africa. METHODS: HIV-positive Zambian adults with new-onset seizure were enrolled in a prospective cohort study to determine seizure recurrence and risk factors for recurrence. Seizure etiology was evaluated, and recurrent seizures and medication usage were assessed during clinic visits. Due to unexpectedly high mortality rates, predictors of death were evaluated using proportional hazards with Gray's test to compare cumulative incidence functions for recurrent seizure across groups adjusting for the competing outcome of death. RESULTS: 95 patients were enrolled (mean age 37 years, 43% female, 83% with Karnofsky > 50) and followed for a mean of 293 days (median 241 (IQR: 29-532)). At presentation, 50 (53%) were in status epilepticus. The majority (91, 85%) had advanced HIV disease and 65 (68%) were not on combined antiretroviral therapy (cART). After extensive workup, seizure etiology remained unknown in 16 (17%). Average time to cART initiation after enrollment was 61 days. During follow up, 37 (39%) died and 23 (24%) had recurrent seizure. Most deaths (25/37, 68%) occurred in the first 60 days post-index seizure. Individuals with advanced HIV were more likely to die (HR: 19.1 [95% CI: 1.1-333.4]) as were those whose seizure etiology remained unknown (HR: 2.2 [95% CI: 1.1-4.4]). Among participants that survived from enrolment to the end of data collection on 10 May 2013 (n = 58), 20 (34%) experienced recurrent seizures. CONCLUSIONS: New-onset seizure among HIV-positive Zambian adults is associated with high mortality despite good functional status prior to presentation. Advanced HIV infection and failure to identify an underlying seizure etiology are associated with greater mortality. Recurrent seizures occur in over a third of survivors within only 2 years of follow-up. This provides evidence to support AED initiation after first seizure in HIV-positive individuals with advanced HIV disease at the time of presentation though the risks of AED-cART interactions remain a concern and warrant further study.
Assuntos
Infecções por HIV/complicações , Convulsões/etiologia , Convulsões/mortalidade , Adulto , Anticonvulsivantes/uso terapêutico , Feminino , Infecções por HIV/mortalidade , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Fatores de Risco , Convulsões/tratamento farmacológico , Adulto Jovem , ZâmbiaAssuntos
Radiologia , Humanos , Zâmbia , Radiologia/educação , Currículo , Radiografia , ComputadoresRESUMO
BACKGROUND: Cerebral malaria (CM) remains a significant cause of morbidity and mortality in children in sub-Saharan Africa. CM mortality has been associated with increased brain volume, seen on neuroimaging studies. METHODS: To examine the potential role of blood metabolites and inflammatory mediators in increased brain volume in Malawian children with CM, an association study was performed between plasma metabolites, cytokine levels and phospholipase A2 (PLA2) activity with brain volume. RESULTS: The metabolomics analysis demonstrated arachidonic acid and other lysophospholipids to be positively associated with brain swelling. These lipids are products of the PLA2 enzyme and an association of plasma PLA2 enzymatic activity with brain swelling was confirmed. TNFα, which can upregulate PLA2 activity, was associated with brain volume. In addition, CCL2 and IL-8 were also associated with brain volume. Some of these cytokines can alter endothelial cell tight junction proteins and increase blood brain barrier permeability. CONCLUSIONS: Taken together, paediatric CM brain volume was associated with products of the PLA2 pathway and inflammatory cytokines. Their role in causality is unknown. These molecules will need to undergo testing in vitro and in animal models to understand their role in processes of increased brain volume. These observations provide novel data on host physiology associated with paediatric CM brain swelling, and may both inform pathogenesis models and suggest adjunct therapies that could improve the morbidity and mortality associated with paediatric CM.
Assuntos
Encéfalo/patologia , Citocinas/sangue , Metabolismo dos Lipídeos , Lipídeos/sangue , Malária Cerebral/patologia , Fosfolipases A2/metabolismo , Animais , Criança , Pré-Escolar , Estudos de Coortes , Humanos , Lactente , MalauiRESUMO
Computed tomography (CT) and magnetic resonance imaging (MRI) have made it relatively easy to diagnose cortical convexity subarachnoid hemorrhages (cSAH); however, the evaluation of these hemorrhages should not be limited to size and location. It is imperative that possible underlying etiologies be identified so that clinicians may properly treat and prevent this potentially catastrophic event. The goal of this article is to review etiologies of cortical convexity subarachnoid hemorrhages, from common causes such as cerebral amyloid angiopathy to less common causes such as reversible cerebral vasoconstriction syndrome and moyamoya. The specific imaging findings of each etiology that may be responsible for these hemorrhages are described in this article so that the radiologist may properly aid in the diagnosis of the underlying cause.
Assuntos
Neuroimagem/métodos , Hemorragia Subaracnóidea/diagnóstico , Hemorragia Subaracnóidea/etiologia , Meios de Contraste , Diagnóstico Diferencial , HumanosRESUMO
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 AssuntoRESUMO
BACKGROUND: There are an estimated 1.5 million children living with human immunodeficiency virus (CLHIV), most residing in sub-Saharan Africa. A common hospital presentation of CLHIV is new-onset seizure, for which imaging is helpful but not routinely performed due to scarce resources. We present imaging findings and their association with clinical risk factors and outcomes in a cohort of Zambian CLHIV presenting with new-onset seizure. METHODS: In this prospective cohort study, participants were recruited at the University Teaching Hospital in Lusaka, Zambia. Various clinical and demographic characteristics were obtained. Computed tomography (CT), magnetic resonance imaging (MRI), or both were obtained during admission or shortly after discharge. If both studies were available, MRI data was used. Two neuroradiologists interpreted images using REDCap-based NeuroInterp, a tool that quantifies brain imaging findings. Age-dependent neuropsychologic assessments were administered. RESULTS: Nineteen of 39 (49%) children had a brain MRI, 16 of 39 (41%) had CT, and four of 39 (10%) had both. Mean age was 6.8 years (S.D. = 4.8). Children with advanced HIV disease had higher odds of atrophy (odds ration [OR] 7.2, 95% confidence interval [CI] 1.1 to 48.3). Focal abnormalities were less likely in children receiving antiretroviral therapy (ART) (OR 0.22, 95% CI 0.05 to 1.0). Children with neurocognitive impairment were more likely to have atrophy (OR 8.4, 95% CI 1.3 to 55.4) and less likely to have focal abnormalities (OR 0.2, 95% CI 0.03 to 0.9). CONCLUSIONS: Focal brain abnormalities on MRI were less likely in CLHIV on ART. Brain atrophy was the most common imaging abnormality, which was linked to severe neurocognitive impairment.
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OBJECTIVE: To determine the long-term outcomes, including mortality and recurrent seizures, among children living with HIV (CLWH) who present with new onset seizure. METHODS: Zambian CLWH and new onset seizure were enrolled prospectively to determine the risk of and risk factors for recurrent seizures. Demographic data, clinical profiles, index seizure etiology, and 30-day mortality outcomes were previously reported. After discharge, children were followed quarterly to identify recurrent seizures and death. Given the high risk of early death, risk factors for recurrent seizure were evaluated using a model that adjusted for mortality. RESULTS: Among 73 children enrolled, 28 died (38%), 22 within 30-days of the index seizure. Median follow-up was 533 days (IQR 18-957) with 5% (4/73) lost to follow-up. Seizure recurrence was 19% among the entire cohort. Among children surviving at least 30-days after the index seizure, 27% had a recurrent seizure. Median time from index seizure to recurrent seizure was 161 days (IQR 86-269). Central nervous system opportunistic infection (CNS OI), as the cause for the index seizure was protective against recurrent seizures and higher functional status was a risk factor for seizure recurrence. SIGNIFICANCE: Among CLWH presenting with new onset seizure, mortality risks remain elevated beyond the acute illness period. Recurrent seizures are common and are more likely in children with higher level of functioning even after adjusting for the outcome of death. Newer antiseizure medications appropriate for co-usage with antiretroviral therapies are needed for the care of these children. CNS OI may represent a potentially reversible provocation for the index seizure, while seizures in high functioning CLWH without a CNS OI may be the result of a prior brain injury or susceptibility to seizures unrelated to HIV and thus represent an ongoing predisposition to seizures. PLAIN LANGUAGE SUMMARY: This study followed CLWH who experienced a new onset seizure to find out how many go on to have more seizures and identify any patient characteristics associated with having more seizures. The study found that mortality rates continue to be high beyond the acute clinical presentation with new onset seizure. Children with a CNS OI causing the new onset seizure had a lower risk of later seizures, possibly because the trigger for the seizure can be treated. In contrast, high functioning children without a CNS OI were at higher risk of future seizures.
Assuntos
Epilepsia Generalizada , Infecções por HIV , Criança , Humanos , Anticonvulsivantes/uso terapêutico , Estudos de Coortes , Convulsões/tratamento farmacológico , Epilepsia Generalizada/tratamento farmacológico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Dano Encefálico Crônico/induzido quimicamente , Dano Encefálico Crônico/complicações , Dano Encefálico Crônico/tratamento farmacológicoRESUMO
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.
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OBJECTIVE: To describe longitudinal outcomes and predictors of cognitive outcomes in children with HIV in Zambia. BACKGROUND: Multiple studies have shown that children with HIV are at risk for impaired cognition. However, there are limited data on longitudinal cognitive outcomes in children with HIV. METHODS: We conducted a prospective cohort study of 208 perinatally infected children with HIV ages 8-17 years, all treated with antiretroviral therapy, and 208 HIV-exposed uninfected controls. Participants were followed for 2 years. Cognition was assessed with a custom NIH Toolbox Cognition Battery, and tests were combined to generate a Summary Cognition Score (SCS). The contribution of potential risk factors to outcomes was explored using regression models and group-based trajectory modeling. RESULTS: HIV was strongly associated with lower SCS at baseline [ß-14, 95% confidence interval (CI): -20 to -7, P < 0.001]. Change scores over time were similar between groups, but poorer average performance in children with HIV persisted at the 2-year follow-up visit (adjusted ß = -11, 95% CI: -22 to -0.3, P = 0.04). Other than HIV, the strongest predictors of baseline SCS included socioeconomic status index (ß =3, 95% CI: 1, 5, P = 0.004), history of growth stunting (ß=-14, 95% CI: -23 to -6, P = 0.001), history of CD4 count below 200 (ß = -19, 95% CI: -35 to -2, P = 0.02), and history of World Health Organization stage 4 disease (ß = -10, 95% CI: -19 to -0.2, P = 0.04). In the group-based trajectory model, HIV+ status predicted membership in the lowest performing trajectory group (odds ratio 2.5, 95% CI: 1.2 to 5.1, P = 0.01). CONCLUSIONS: Children with HIV are at risk of poor cognitive outcomes, despite chronic treatment with antiretroviral therapy.
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Infecções por HIV , Adolescente , Criança , Cognição , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Transtornos Neurocognitivos/complicações , Estudos Prospectivos , Zâmbia/epidemiologiaRESUMO
BACKGROUND: Multiple previous studies have identified a detrimental effect of pediatric HIV on cognitive function. Socioeconomic status (SES) is one of the strongest predictors of cognitive performance and may affect the relationship between HIV and cognition. METHODS: As part of the ongoing HIV-Associated Neurocognitive Disorders in Zambia (HANDZ) study, a prospective cohort study, we recruited 208 participants with HIV and 208 HIV-exposed uninfected controls, all aged 8-17 years. A standardized questionnaire was administered to assess SES, and all participants had comprehensive neuropsychological testing. An NPZ8 score was derived as a summary measure of cognitive function. Logistic regression and linear regression were used to model the relationship between SES and cognitive function, and mediation analysis was used to identify specific pathways by which SES may affect cognition. RESULTS: Children with HIV performed significantly worse on a composite measure of cognitive function (NPZ8 score -0.19 vs. 0.22, P < 0.001) and were more likely to have cognitive impairment (33% vs. 19%, P = 0.001). Higher SES was associated with reduced risk of cognitive impairment (odds ratio 0.8, 95% confidence interval: 0.75-0.92, P < 0.001) in both groups, with similar effects in children with HIV and HIV-exposed uninfected groups. SES was more strongly correlated with NPZ8 score in children with HIV than in uninfected controls (Pearson's R 0.39 vs. 0.28), but predicted NPZ8 in both groups. Mediation analysis suggested that the effect of SES on cognition was most strongly mediated through malnutrition. CONCLUSIONS: Cognitive function is strongly correlated with SES in children with HIV, suggesting a synergistic effect of HIV and poverty on cognitive function.
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Infecções por HIV , Adolescente , Criança , Cognição , Infecções por HIV/psicologia , Humanos , Transtornos Neurocognitivos/complicações , Transtornos Neurocognitivos/epidemiologia , Estudos Prospectivos , Classe Social , Zâmbia/epidemiologiaRESUMO
OBJECTIVE: This study describes clinical profiles including human immunodeficiency virus (HIV) disease history and seizure etiology among children living with HIV presenting with new-onset seizure during the era of antiretroviral therapy (ART) in Zambia. 30-day mortality and cause of death are also reported. METHODS: Children living with HIV (CLWHIV) with new-onset seizures were prospectively evaluated at one large urban teaching hospital and two non-urban healthcare facilities. Interviews with family members, review of medical records, and where needed, verbal autopsies were undertaken. Two clinicians who were not responsible for the patients' care independently reviewed all records and assigned seizure etiology and cause of death with adjudication as needed. RESULTS: From April 2016 to June 2019, 73 children (49 urban, 24 rural) were identified. Median age was 6 years (IQR 2.2-10.0) and 39 (53%) were male children. Seizures were focal in 36 (49%) and were often severe, with 37% presenting with multiple recurrent seizures in the 24 hours before admission or in status epilepticus. Although 36 (49%) were on ART at enrollment, only 7 of 36 (19%) were virally suppressed. Seizure etiologies were infectious in over half (54%), with HIV encephalitis, bacterial meningitis, and tuberculous meningitis being the most common. Metabolic causes (19%) included renal failure and hypoglycemia. Structural lesions identified on imaging accounted for 10% of etiologies and included stroke and non-accidental trauma. No etiology could be identified in 12 (16%) children, most of whom died before the completion of clinical investigations. Twenty-two (30%) children died within 30 days of the index seizure. SIGNIFICANCE: Despite widespread ART roll out in Zambia, new-onset seizure in CLWHIV occurs in the setting of advanced, active HIV disease. Seizure severity/burden is high as is early mortality. Enhanced programs to assure early ART initiation, improve adherence, and address ART failure are needed to reduce the burden of neurological injury and premature death in CLWHIV.
Assuntos
Complexo AIDS Demência , Infecções por HIV , Complexo AIDS Demência/complicações , Criança , Pré-Escolar , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , População Rural , Convulsões/tratamento farmacológico , Convulsões/etiologia , ZâmbiaRESUMO
As part of an NIH-funded study of malaria pathogenesis, a magnetic resonance (MR) imaging research facility was established in Blantyre, Malawi to enhance the clinical characterization of pediatric patients with cerebral malaria through application of neurological MR methods. The research program requires daily transmission of MR studies to Michigan State University (MSU) for clinical research interpretation and quantitative post-processing. An intercontinental satellite-based network was implemented for transmission of MR image data in Digital Imaging and Communications in Medicine (DICOM) format, research data collection, project communications, and remote systems administration. Satellite Internet service costs limited the bandwidth to symmetrical 384 kbit/s. DICOM routers deployed at both the Malawi MRI facility and MSU manage the end-to-end encrypted compressed data transmission. Network performance between DICOM routers was measured while transmitting both mixed clinical MR studies and synthetic studies. Effective network latency averaged 715 ms. Within a mix of clinical MR studies, the average transmission time for a 256 × 256 image was ~2.25 and ~6.25 s for a 512 × 512 image. Using synthetic studies of 1,000 duplicate images, the interquartile range for 256 × 256 images was [2.30, 2.36] s and [5.94, 6.05] s for 512 × 512 images. Transmission of clinical MRI studies between the DICOM routers averaged 9.35 images per minute, representing an effective channel utilization of ~137% of the 384-kbit/s satellite service as computed using uncompressed image file sizes (including the effects of image compression, protocol overhead, channel latency, etc.). Power unreliability was the primary cause of interrupted operations in the first year, including an outage exceeding 10 days.
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Pesquisa Biomédica , Imageamento por Ressonância Magnética , Malária/diagnóstico , Comunicações Via Satélite , Países em Desenvolvimento , Fontes de Energia Elétrica , Humanos , Interpretação de Imagem Assistida por Computador , Malária/epidemiologia , Malaui/epidemiologia , Michigan , Microcomputadores , Pediatria/métodosRESUMO
BACKGROUND: Place-based inequalities, such as exposure to violence and access to nutritious food and clean water, may contribute to human immunodeficiency virus (HIV)-associated cognitive impairment. In this study, we investigated neighborhood effects on cognition in children and adolescents with HIV in Lusaka, Zambia. METHODS: We conducted a prospective cohort study of 208 children with perinatally acquired HIV (ages 8-17) and 208 HIV-exposed uninfected controls. Participants underwent neuropsychological testing and interviews assessing socioeconomic status. Geographic regions with clusters of participants with HIV and cognitive impairment were identified using quantitative geographic information systems (QGIS) and SaTScan. Associations between location of residence and cognitive function were evaluated in bivariable and multivariable regression models. Mediation analysis was performed to assess direct and indirect effects of location of the residence on cognitive impairment. RESULTS: Residence in Chawama, one of the poorest neighborhoods in Lusaka, was significantly associated with cognitive impairment in participants with HIV (odds ratio 2.9; Pâ =â .005) and remained significant in a multivariable regression model controlling for potential confounders. Mediation analysis found that 46% of the cognitive effects of residence in Chawama were explained by higher rates of malnutrition, lower school attendance, and poorer self-reported health. CONCLUSIONS: Place-based socioeconomic inequality contributes to cognitive impairment in Zambian children and adolescents with HIV. Neighborhood effects may be mediated by concentrated poverty, malnutrition, limited access to education and health care, and other yet unknown environmental factors that may be potentially modifiable.
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Disfunção Cognitiva , Infecções por HIV , Adolescente , Criança , Disfunção Cognitiva/epidemiologia , Sistemas de Informação Geográfica , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Estudos Prospectivos , Fatores Socioeconômicos , Zâmbia/epidemiologiaRESUMO
BACKGROUND: Cerebral malaria (CM) remains a leading cause of mortality and morbidity in children in sub-Saharan Africa. Recent studies using brain magnetic resonance imaging have revealed increased brain volume as a major predictor of death. Similar morphometric predictors of morbidity at discharge are lacking. The aim of this study was to investigate the utility of serial cranial cisternal cerebrospinal fluid (CSF) volume measurements in predicting morbidity at discharge in pediatric CM survivors. METHODS: In this case-control study, 54 Malawian pediatric CM survivors with neurologic sequelae evident at discharge who underwent serial magnetic resonance imaging scans while comatose were matched to concurrently admitted children with serial imaging who made full recoveries. Serial cranial cisternal CSF volume quantified by radiologists blinded to outcome was evaluated as a predictor of neurologic deficits at discharge. The probability of neurologic sequelae was determined using a model that included coma duration and changes in cisternal CSF volume over time. RESULTS: Coma duration before admission was similar between cases and controls (16.1 vs. 15.3; P = 0.81), but overall coma was longer among children with sequelae (60 vs. 38 hours; P < 0.01). Lower initial CSF volumes and decreased volumes over time were both associated with a higher probability of neurologic sequelae at discharge. CONCLUSIONS: Among pediatric CM survivors with prolonged coma, lower initial CSF volume and decreasing volume during coma is associated with neurologic sequelae at discharge. These findings suggest that cerebral edema is an underlying contributor to both morbidity and mortality in pediatric CM.
Assuntos
Edema Encefálico/líquido cefalorraquidiano , Edema Encefálico/parasitologia , Coma/líquido cefalorraquidiano , Malária Cerebral/complicações , Sobreviventes/estatística & dados numéricos , Edema Encefálico/mortalidade , Estudos de Casos e Controles , Criança , Pré-Escolar , Coma/parasitologia , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Malária Cerebral/líquido cefalorraquidiano , Malária Cerebral/diagnóstico por imagem , Malaui , Masculino , Morbidade , Convulsões , Centros de Atenção TerciáriaRESUMO
BACKGROUND: Cognitive impairment is common in children and adolescents with human immunodeficiency virus (HIV). Brain magnetic resonance imaging (MRI) is a potentially useful tool to investigate the pathophysiology of HIV-associated cognitive impairment and may serve as a biomarker in future clinical trials. There are few published data on brain imaging in children with HIV in sub-Saharan Africa. METHODS: Thirty-four perinatally infected subjects with HIV and age-matched HIV-exposed uninfected controls between the ages nine and 17 years were recruited from the Pediatric Center of Excellence in Lusaka, Zambia, as part of the HIV-associated Neurocognitive Disorders in Zambia study. Brain MRI sequences were acquired, and clinical and volumetric assessments were performed. Subjects underwent a comprehensive neuropsychologic battery, and cognitive impairment status was classified using a global deficit score approach. Regression models were used to evaluate relationships between MRI findings and cognitive function. RESULTS: We identified cerebrovascular disease in seven of 34 subjects with HIV compared with zero of 17 controls (21% vs 0%, P = 0.04). We also identified decreased total brain volumes (1036 vs 1162 cm3, P = 0.03) and decreased cortical thickness in the right temporal lobes (3.12 vs 3.29 mm; P = 0.01) and right fusiform gyri (3.10 vs 3.25 mm; P = 0.02) of HIV-infected subjects with cognitive impairment. CONCLUSIONS: These findings support the hypothesis that brain volumes may be useful biomarkers for cognitive outcomes in children with HIV. Further studies are necessary to investigate mechanisms of cerebrovascular disease and volume loss in children with HIV.
Assuntos
Encéfalo/diagnóstico por imagem , Transtornos Cerebrovasculares/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Infecções por HIV/diagnóstico por imagem , Adolescente , Encéfalo/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Transtornos Cerebrovasculares/etiologia , Transtornos Cerebrovasculares/patologia , Criança , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Feminino , Infecções por HIV/complicações , Humanos , Transmissão Vertical de Doenças Infecciosas , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , ZâmbiaRESUMO
BACKGROUND: High rates of cerebrovascular disease (CVD) have previously been described in pediatric human immunodeficiency virus (HIV). However, little is known about pediatric CVD in the era of antiretroviral therapy or about the contribution of CVD to HIV-associated neurocognitive disorders. METHODS: We completed a neuroimaging substudy of the HIV-Associated Neurocognitive Disorders in Zambia study, a prospective cohort study of neurocognitive complications of pediatric HIV. Brain magnetic resonance imaging (1.5 T) was acquired for 34 HIV+ children on antiretroviral therapy and 17 HIV-exposed uninfected children (aged eight to 17 years). Demographics, medical history, neurological examination, and neuropsychologic testing results were collected. Two neuroradiologists, unaware of HIV status and clinical course, read the scans. RESULTS: CVD was identified in seven of 34 children with HIV (HIV+ CVD+) and no HIV-exposed uninfected children (21% vs 0%, P = 0.05). Three participants had white matter changes suggestive of small vessel disease, four had infarcts, and two had evidence of intracranial artery stenosis. Age of antiretroviral therapy initiation and exposure to protease inhibitors or efavirenz was not significantly different between children with and without CVD. HIV+ CVD+ children had significantly worse scores on a summary measure of cognition than the HIV+ CVD- group (NPZ8 score -0.57 vs 0.33, P = 0.04). CONCLUSIONS: This study demonstrates high rates of CVD in children with HIV despite antiretroviral therapy, and worse cognitive performance in children with CVD. Longitudinal studies are necessary to determine the mechanisms and incidence of new-onset CVD in children with HIV.