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Shekarau E, Uzoanya M, Ogbulafor N. Severe malaria intervention status in Nigeria: workshop meeting report. Malar J 2024; 23:177. [PMID: 38840162 PMCID: PMC11155025 DOI: 10.1186/s12936-024-05001-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Accepted: 05/26/2024] [Indexed: 06/07/2024] Open
Abstract
Nigeria accounts for 39% of global malaria deaths in children under 5 years of age and the effective management of severe malaria is a health priority. The Annual Nigeria Severe Malaria Stakeholders Workshop, held on the 5-6th of July 2023 in Abuja, Nigeria brought together representatives from 36 States, the Federal Capital Territory, and other key stakeholders to address the management of severe malaria across all levels of the health service. Aims were to provide updates and review progress on severe malaria activities, the burden of disease, commodity logistics management, and pre-referral national policy implementation as well as to disseminate research findings. Two roundtable discussions were conducted to identify the challenges, barriers, and facilitators to the effective management of severe malaria in Nigeria. A key challenge was the limited awareness of updated guidelines and strategic documents among frontline health workers, leading to the misuse of non-recommended medications, like α-β-arteether. Further to this, the need to ensure appropriate treatments during pregnancy and the adoption of the WHO directive on the use of rectal artesunate were highlighted. To address these issues, innovative dissemination channels for guideline awareness were recommended and collaboration with professional organizations to enrich training materials emphasized. Other areas for improvement considered the processes involved in severe malaria management, with insufficient coordination among government agencies, inadequate referral linkages, and inadequate human resources identified as barriers. Recommendations focused on practical measures to minimize wastage of injectable artesunate, enhance data management through scaling up electronic medical records, and strengthen referral systems. The extension of severe malaria surveillance to patients older than 5 years was also proposed. To deliver these changes, actionable plans for sustained recruitment and training are needed, as well as committed advocacy at all levels to ensure timely fund disbursement and institutional support. A key overarching theme from the workshop was that a multifaceted approach was needed to address severe malaria in Nigeria, emphasizing collaborative efforts, evidence-based practices, and strategic resource allocation. With the largest malaria burden globally, the potential impact of addressing the challenges of severe malaria management in Nigeria cannot be understated and must be urgently addressed.
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Affiliation(s)
- Emmanuel Shekarau
- National Malaria Elimination Programme, Public Health Department, Federal Ministry of Health, Abuja, Federal Capital Territory, Nigeria
| | - Miriam Uzoanya
- National Malaria Elimination Programme, Public Health Department, Federal Ministry of Health, Abuja, Federal Capital Territory, Nigeria
| | - Nnenna Ogbulafor
- National Malaria Elimination Programme, Public Health Department, Federal Ministry of Health, Abuja, Federal Capital Territory, Nigeria.
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Gomes C, Varo R, Duran-Frigola M, Sitoe A, Bila R, Machevo S, Mayor A, Bassat Q, Rodriguez A. Endothelial transcriptomic analysis identifies biomarkers of severe and cerebral malaria. JCI Insight 2023; 8:e172845. [PMID: 37788095 PMCID: PMC10721316 DOI: 10.1172/jci.insight.172845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 09/28/2023] [Indexed: 10/05/2023] Open
Abstract
Malaria can quickly progress from an uncomplicated infection into a life-threatening severe disease. However, the unspecificity of early symptoms often makes it difficult to identify patients at high risk of developing severe disease. Additionally, one of the most feared malaria complications - cerebral malaria - is challenging to diagnose, often resulting in treatment delays that can lead to adverse outcomes. To identify candidate biomarkers for the prognosis and/or diagnosis of severe and cerebral malaria, we have analyzed the transcriptomic response of human brain microvascular endothelial cells to erythrocytes infected with Plasmodium falciparum. Candidates were validated in plasma samples from a cohort of pediatric patients with malaria from Mozambique, resulting in the identification of several markers with capacity to distinguish uncomplicated from severe malaria, the most potent being the metallopeptidase ADAMTS18. Two other biomarkers, Angiopoietin-like-4 and Inhibin-βE were able to differentiate children with cerebral malaria within the severe malaria group, showing increased sensitivity after combination in a biomarker signature. The validation of the predicted candidate biomarkers in plasma of children with severe and cerebral malaria underscores the power of this transcriptomic approach and indicates that a specific endothelial response to P. falciparum-infected erythrocytes is linked to the pathophysiology of severe malaria.
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Affiliation(s)
- Cláudia Gomes
- New York University Grossman School of Medicine, New York, USA
| | - Rosauro Varo
- ISGlobal, Hospital Clínic — University of Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | | | - Antonio Sitoe
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Rubão Bila
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Sonia Machevo
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Alfredo Mayor
- ISGlobal, Hospital Clínic — University of Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- Spanish Consortium for Research in Epidemiology and Public Health (CIBERESP), Carlos III Health Institute, Madrid, Spain
- Department of Physiologic Sciences, Faculty of Medicine, Universidade Eduardo Mondlane, Maputo, Mozambique
| | - Quique Bassat
- ISGlobal, Hospital Clínic — University of Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- Spanish Consortium for Research in Epidemiology and Public Health (CIBERESP), Carlos III Health Institute, Madrid, Spain
- ICREA, Pg. Lluís Companys 23, Barcelona, Spain
- Pediatrics Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Esplugues, Barcelona, Spain
| | - Ana Rodriguez
- New York University Grossman School of Medicine, New York, USA
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Savonius O, de Souza CF, Fançony C, Cruzeiro ML, Brito M, Pelkonen T. PCR-confirmed malaria among children presenting with a decreased level of consciousness in Angola: a prospective, observational study. Malar J 2023; 22:130. [PMID: 37087435 PMCID: PMC10122800 DOI: 10.1186/s12936-023-04556-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 04/07/2023] [Indexed: 04/24/2023] Open
Abstract
BACKGROUND In malaria-endemic areas, children presenting to hospitals with a decreased level of consciousness remain a diagnostic dilemma. The definition of cerebral malaria in a comatose child demands exclusion of other possible reasons, which requires in-depth investigations that are not easily available. The aim of this study was to investigate the frequency and clinical characteristics of PCR-confirmed malaria in a cohort of children with a decreased level of consciousness, look for potential features that would aid in differentiating children with malaria from those without, and assess the performance of traditional thick film microscopy against the cytb-qPCR-method. METHODS A total of 345 children aged 30 days-15 years old, presenting to Hospital Pediátrico David Bernardino in Luanda, Angola, with a decreased level of consciousness (Glasgow coma scale score < 15) were prospectively enrolled during 2014-2017. Malaria was defined as a positive cytb-qPCR result on any occasion in hospital. The clinical course and laboratory parameters were compared between children with malaria and those without. The performance of thick film microscopy was analysed against the PCR method. RESULTS 161 of 345 children (46.7%) had a positive malaria PCR test result. All cases were Plasmodium falciparum species, and 82.6% (133/161) fulfilled the WHO criteria for severe malaria. Overall, children with malaria presented to hospital with a shorter duration of symptoms and less convulsions pre-admission compared to those without malaria. The median GCS score on admission was 8, which did not differ between children with or without malaria. Clinical findings on admission were mostly similar across the whole cohort, but an infection focus outside the central nervous system was more common in malaria-negative children. Moreover, severe anaemia, thrombocytopenia, and high CRP levels occurred more frequently in children with malaria. The case fatality ratio was 28.5% (91/319) and did not differ between parasitaemic children and those without malaria, although parasitaemic children died sooner after hospital admission. When neurological sequelae were also considered, a positive malaria test was associated with a better outcome. The performance of thick film microscopy against PCR yielded a sensitivity of 96.8% and a specificity of 82.7%. CONCLUSIONS In this cohort of children with a decreased consciousness, the frequent presence of a malarial infection could not be judged from the clinical findings on admission, but the combination of profound aneamia, thrombocytopenia, and a high CRP level increased the odds of a positive malaria test result. Mortality remained high regardless of etiology, but malaria infection associated with fewer neurological deficits at discharge. Thick film microscopy performed well compared to the cytb-qPCR method.
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Affiliation(s)
- Okko Savonius
- New Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Stenbäckinkatu 9, 00290, Helsinki, Finland.
| | - Cintia F de Souza
- Health and Technology Research Center, Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Lisbon, Portugal
- Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (IOC-Fiocruz), Rio de Janeiro, Brazil
| | - Cláudia Fançony
- Centro de Investigação em Saúde de Angola (CISA), Caxito, Angola
| | | | - Miguel Brito
- Health and Technology Research Center, Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Lisbon, Portugal
- Centro de Investigação em Saúde de Angola (CISA), Caxito, Angola
| | - Tuula Pelkonen
- New Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Stenbäckinkatu 9, 00290, Helsinki, Finland
- Hospital Pediátrico David Bernardino, Luanda, Angola
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Omoleye D, Israr MA, Tazin F, Celeste C, Saheed O. Cerebral Malaria Presenting With Shock in an Adolescent: A Case Report. Cureus 2022; 14:e29025. [PMID: 36237822 PMCID: PMC9552573 DOI: 10.7759/cureus.29025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/11/2022] [Indexed: 12/02/2022] Open
Abstract
Cerebral malaria (CM) is a severe infection of the brain caused by the parasite Plasmodium falciparum. It is commonly found as a complication of infection traveling to the brain. CM has a poor prognosis unless promptly identified and treated. This case report describes a 15-year-old girl who suddenly started experiencing a tonic-clonic seizure while playing. At the time of arrival at the emergency department, her vital signs were consistent with shock. She had hepatomegaly on physical examination, a hallmark of malarial infection due to an immune response against the proliferation of the protozoa. Peripheral blood smear for malaria parasites was positive for P. falciparum and P. vivax. The patient was started on intravenous (IV) saline, IV phenytoin, and IV metoclopramide. She was also transfused with two units of packed red blood cells. The patient was subsequently diagnosed with CM. For most patients, the course of treatment includes aggressive therapy with anti-malarial medications. She was started on broad-spectrum antibiotics and anti-malarial medications. Following two weeks of treatment, her condition improved significantly and she was discharged.
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Brunner NC, Awor P, Hetzel MW. Definitions of Severity in Treatment Seeking Studies of Febrile Illness in Children in Low and Middle Income Countries: A Scoping Review. Int J Public Health 2021; 66:634000. [PMID: 34526874 PMCID: PMC8435535 DOI: 10.3389/ijph.2021.634000] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 08/06/2021] [Indexed: 01/02/2023] Open
Abstract
Objectives: Understanding treatment seeking for severe febrile illness (SFI) is methodologically challenging. In this scoping review, we investigate definitions of severe febrile illness in treatment seeking studies on children under 5 years of age in low and middle income countries. We analyze the association of SFI definitions with different concepts of treatment seeking and identify related research gaps. Methods: We searched Pubmed, Scopus and WHOLIS, and screened references of included publications for eligibility. Results: Definitions of SFI had either a biomedical perspective (predominantly in quantitative studies) or a caregiver perspective (predominantly in qualitative studies). In quantitative analyses of treatment seeking, severity was more often conceptualized as a determinant rather than an outcome of a treatment seeking process. The majority of quantitative analyses only included surviving children or did not explicitly mention dead children. Conclusion: Different research questions lead to diverse definitions and concepts of severity and treatment seeking outcomes, which limits the comparability of the available evidence. Systematic exclusion of dead children is likely to bias inferences on the association of treatment seeking and health outcomes of children with SFI in low and middle income countries.
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Affiliation(s)
- Nina C Brunner
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Phyllis Awor
- Department of Community Health and Behavioural Sciences, Makerere University School of Public Health, Kampala, Uganda
| | - Manuel W Hetzel
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
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Obiero CW, Mturi N, Mwarumba S, Ngari M, Newton CR, van Hensbroek MB, Berkley JA. Clinical features of bacterial meningitis among hospitalised children in Kenya. BMC Med 2021; 19:122. [PMID: 34082778 PMCID: PMC8176744 DOI: 10.1186/s12916-021-01998-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 04/29/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Diagnosing bacterial meningitis is essential to optimise the type and duration of antimicrobial therapy to limit mortality and sequelae. In sub-Saharan Africa, many public hospitals lack laboratory capacity, relying on clinical features to empirically treat or not treat meningitis. We investigated whether clinical features of bacterial meningitis identified prior to the introduction of conjugate vaccines still discriminate meningitis in children aged ≥60 days. METHODS We conducted a retrospective cohort study to validate seven clinical features identified in 2002 (KCH-2002): bulging fontanel, neck stiffness, cyanosis, seizures outside the febrile convulsion age range, focal seizures, impaired consciousness, or fever without malaria parasitaemia and Integrated Management of Childhood Illness (IMCI) signs: neck stiffness, lethargy, impaired consciousness or seizures, and assessed at admission in discriminating bacterial meningitis after the introduction of conjugate vaccines. Children aged ≥60 days hospitalised between 2012 and 2016 at Kilifi County Hospital were included in this analysis. Meningitis was defined as positive cerebrospinal fluid (CSF) culture, organism observed on CSF microscopy, positive CSF antigen test, leukocytes ≥50/μL, or CSF to blood glucose ratio <0.1. RESULTS Among 12,837 admissions, 98 (0.8%) had meningitis. The presence of KCH-2002 signs had a sensitivity of 86% (95% CI 77-92) and specificity of 38% (95% CI 37-38). Exclusion of 'fever without malaria parasitaemia' reduced sensitivity to 58% (95% CI 48-68) and increased specificity to 80% (95% CI 79-80). IMCI signs had a sensitivity of 80% (95% CI 70-87) and specificity of 62% (95% CI 61-63). CONCLUSIONS A lower prevalence of bacterial meningitis and less typical signs than in 2002 meant the lower performance of KCH-2002 signs. Clinicians and policymakers should be aware of the number of lumbar punctures (LPs) or empirical treatments needed for each case of meningitis. Establishing basic capacity for CSF analysis is essential to exclude bacterial meningitis in children with potential signs.
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Affiliation(s)
- Christina W Obiero
- Clinical Research Department, KEMRI-Wellcome Trust Research Programme, P.O. Box 230 80108, Kilifi, Kenya.
- Department of Global Health, Faculty of Medicine, University of Amsterdam, Amsterdam, The Netherlands.
| | - Neema Mturi
- Clinical Research Department, KEMRI-Wellcome Trust Research Programme, P.O. Box 230 80108, Kilifi, Kenya
| | - Salim Mwarumba
- Department of Microbiology, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Moses Ngari
- Clinical Research Department, KEMRI-Wellcome Trust Research Programme, P.O. Box 230 80108, Kilifi, Kenya
- The Childhood Acute Illness and Nutrition (CHAIN) Network, Nairobi, Kenya
| | - Charles R Newton
- Clinical Research Department, KEMRI-Wellcome Trust Research Programme, P.O. Box 230 80108, Kilifi, Kenya
- Department of Psychiatry, University of Oxford, Oxford, UK
| | | | - James A Berkley
- Clinical Research Department, KEMRI-Wellcome Trust Research Programme, P.O. Box 230 80108, Kilifi, Kenya
- The Childhood Acute Illness and Nutrition (CHAIN) Network, Nairobi, Kenya
- Centre for Tropical Medicine & Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
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Obiero CW, Mturi N, Mwarumba S, Ngari M, Newton C, Boele van Hensbroek M, Berkley JA. Clinical features to distinguish meningitis among young infants at a rural Kenyan hospital. Arch Dis Child 2021; 106:130-136. [PMID: 32819909 PMCID: PMC7841476 DOI: 10.1136/archdischild-2020-318913] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 06/23/2020] [Accepted: 07/01/2020] [Indexed: 11/23/2022]
Abstract
BACKGROUND Detection of meningitis is essential to optimise the duration and choice of antimicrobial agents to limit mortality and sequelae. In low and middle-income countries most health facilities lack laboratory capacity and rely on clinical features to empirically treat meningitis. OBJECTIVE We conducted a diagnostic validation study to investigate the performance of clinical features (fever, convulsions, irritability, bulging fontanel and temperature ≥39°C) and WHO-recommended signs (drowsiness, lethargy, unconsciousness, convulsions, bulging fontanel, irritability or a high-pitched cry) in discriminating meningitis in young infants. DESIGN Retrospective cohort study. SETTING Kilifi County Hospital. PATIENTS Infants aged <60 days hospitalised between 2012 and 2016. MAIN OUTCOME MEASURE Definite meningitis defined as positive cerebrospinal fluid (CSF) culture, microscopy or antigen test, or leucocytes ≥0.05 x 10∧9/L. RESULTS Of 4809 infants aged <60 days included, 81 (1.7%) had definite meningitis. WHO-recommended signs had sensitivity of 58% (95% CI 47% to 69%) and specificity of 57% (95% CI 56% to 59%) for definite meningitis. Addition of history of fever improved sensitivity to 89% (95% CI 80% to 95%) but reduced specificity to 26% (95% CI 25% to 27%). Presence of ≥1 of 5 previously identified signs had sensitivity of 79% (95% CI 69% to 87%) and specificity of 51% (95% CI 50% to 53%). CONCLUSIONS Despite a lower prevalence of definite meningitis, the performance of previously identified signs at admission in predicting meningitis was unchanged. Presence of history of fever improves the sensitivity of WHO-recommended signs but loses specificity. Careful evaluation, repeated assessment and capacity for lumbar puncture and CSF microscopy to exclude meningitis in most young infants with potential signs are essential to management in this age group.
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Affiliation(s)
- Christina W Obiero
- Clinical Research Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Global Health, University of Amsterdam Faculty of Medicine, Amsterdam, Noord-Holland, The Netherlands
| | - Neema Mturi
- Clinical Research Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Salim Mwarumba
- Department of Microbiology, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Moses Ngari
- Clinical Research Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- The Childhood Acute Illness and Nutrition (CHAIN) Network, Nairobi, Kenya
| | - Charles Newton
- Clinical Research Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Psychiatry, University of Oxford Centre for Tropical Medicine and Global Health, Oxford, Oxfordshire, UK
| | - Michael Boele van Hensbroek
- Department of Global Health, University of Amsterdam Faculty of Medicine, Amsterdam, Noord-Holland, The Netherlands
| | - James Alexander Berkley
- Clinical Research Department, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- The Childhood Acute Illness and Nutrition (CHAIN) Network, Nairobi, Kenya
- Nuffield Department of Medicine, University of Oxford Centre for Tropical Medicine and Global Health, Oxford, Oxfordshire, UK
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Patel H, Dunican C, Cunnington AJ. Predictors of outcome in childhood Plasmodium falciparum malaria. Virulence 2020; 11:199-221. [PMID: 32063099 PMCID: PMC7051137 DOI: 10.1080/21505594.2020.1726570] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/16/2020] [Accepted: 01/20/2020] [Indexed: 12/16/2022] Open
Abstract
Plasmodium falciparum malaria is classified as either uncomplicated or severe, determining clinical management and providing a framework for understanding pathogenesis. Severe malaria in children is defined by the presence of one or more features associated with adverse outcome, but there is wide variation in the predictive value of these features. Here we review the evidence for the usefulness of these features, alone and in combination, to predict death and other adverse outcomes, and we consider the role that molecular biomarkers may play in augmenting this prediction. We also examine whether a more personalized approach to predicting outcome for specific presenting syndromes of severe malaria, particularly cerebral malaria, has the potential to be more accurate. We note a general need for better external validation in studies of outcome predictors and for the demonstration that predictors can be used to guide clinical management in a way that improves survival and long-term health.
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Affiliation(s)
- Harsita Patel
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, UK
| | - Claire Dunican
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, UK
| | - Aubrey J. Cunnington
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, UK
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Abstract
BACKGROUND Polysaccharide conjugate vaccines (PCVs) target the pneumococcal capsular types that most commonly cause fatal pneumonia and sepsis. Because these types were eliminated by the vaccines, it became apparent that in immunized populations, most invasive pneumococcal diseases, including bacteremia, sepsis and complicated pneumonia, were greatly reduced. However, the protective effects of PCVs against another invasive disease, meningitis, has shown much less or no decrease in disease incidence. METHODS References were identified through searches of PubMed for articles published from January 1930 to the present by use of specific search terms. Relevant articles were also identified through searches in Google and Google Scholar. Relevant references cited in those articles were also reviewed. RESULTS Even in the presence of the PCVs, meningitis rates in children have been reported globally to be as high as 13 per 100,000 annually. Widespread use of vaccines resulted in the emergence of a broad diversity of replacement non-PCV type strains. These strains generally failed to cause sepsis, but caused meningitis of comparable severity and levels similar to, or in excess of, prior pneumococcal meningitis rates. This is probably because these non-PCV type strains do not survive well in the blood, therefore possibly entering the brain through nonhematogenous routes. CONCLUSIONS Because virtually all cases of pneumococcal meningitis lead to either permanent neurologic sequelae or death, it would be well worth the effort to develop a new vaccine capable of preventing pneumococcal meningitis regardless of capsular type. Such a vaccine would need to protect against colonization with most, if not all, pneumococci.
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Affiliation(s)
| | - David E Briles
- Department of Microbiology and Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama
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10
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A biomarker approach to syndrome-based treatment of severe childhood illness in malaria-endemic areas. Malar J 2018; 17:378. [PMID: 30348160 PMCID: PMC6198421 DOI: 10.1186/s12936-018-2533-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 10/18/2018] [Indexed: 11/23/2022] Open
Abstract
This opinion article deals with the diagnostic clinical challenges faced by clinicians or health care workers in malaria-endemic areas when a severely sick child presents to the clinic with fever, coma or respiratory distress. Indeed, the coexistence of malaria with other severe infections like meningitis, invasive bacterial infection or pneumonia makes appropriate treatment allocation a matter of life and death. The use of biomarkers has been proposed as a potential solution to this problem. The arrival of high-throughput technologies allowed thousands of molecules (transcripts, proteins and metabolites) to be been screened in clinical samples from large cohorts of well/characterised patients. The major aim of these studies was to identify biomarkers that inform important decisions: should this child be referred to hospital? Should antibiotics, anti-malarials, or both, be administered? There is a large discrepancy between the number of biomarker discovery studies published and the number of biomarkers that have been clinically validated, let alone implemented. This article reflects on the many opportunities and obstacles encountered in biomarker research in malaria-endemic areas.
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Njunge JM, Oyaro IN, Kibinge NK, Rono MK, Kariuki SM, Newton CR, Berkley JA, Gitau EN. Cerebrospinal fluid markers to distinguish bacterial meningitis from cerebral malaria in children. Wellcome Open Res 2017; 2:47. [PMID: 29181450 PMCID: PMC5686508 DOI: 10.12688/wellcomeopenres.11958.2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/11/2017] [Indexed: 12/23/2022] Open
Abstract
Background. Few hospitals in high malaria endemic countries in Africa have the diagnostic capacity for clinically distinguishing acute bacterial meningitis (ABM) from cerebral malaria (CM). As a result, empirical use of antibiotics is necessary. A biochemical marker of ABM would facilitate precise clinical diagnosis and management of these infections and enable rational use of antibiotics. Methods. We used label-free protein quantification by mass spectrometry to identify cerebrospinal fluid (CSF) markers that distinguish ABM (n=37) from CM (n=22) in Kenyan children. Fold change (FC) and false discovery rates (FDR) were used to identify differentially expressed proteins. Subsequently, potential biomarkers were assessed for their ability to discriminate between ABM and CM using receiver operating characteristic (ROC) curves. Results. The host CSF proteome response to ABM ( Haemophilusinfluenza and Streptococcuspneumoniae) is significantly different to CM. Fifty two proteins were differentially expressed (FDR<0.01, Log FC≥2), of which 83% (43/52) were upregulated in ABM compared to CM. Myeloperoxidase and lactotransferrin were present in 37 (100%) and 36 (97%) of ABM cases, respectively, but absent in CM (n=22). Area under the ROC curve (AUC), sensitivity, and specificity were assessed for myeloperoxidase (1, 1, and 1; 95% CI, 1-1) and lactotransferrin (0.98, 0.97, and 1; 95% CI, 0.96-1). Conclusion. Myeloperoxidase and lactotransferrin have a high potential to distinguish ABM from CM and thereby improve clinical management. Their validation requires a larger cohort of samples that includes other bacterial aetiologies of ABM.
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Affiliation(s)
- James M Njunge
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research Coast, Kilifi, Kenya
| | - Ian N Oyaro
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research Coast, Kilifi, Kenya.,University of Nairobi, Nairobi, Kenya
| | - Nelson K Kibinge
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research Coast, Kilifi, Kenya
| | - Martin K Rono
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research Coast, Kilifi, Kenya.,Pwani University Health and Research Institute, Pwani University, Kilifi, Kenya
| | - Symon M Kariuki
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research Coast, Kilifi, Kenya
| | - Charles R Newton
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research Coast, Kilifi, Kenya.,Department of Psychiatry, Medical Sciences Division, University of Oxford, Oxford, OX3 7JX, UK
| | - James A Berkley
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research Coast, Kilifi, Kenya.,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, OX3 7FZ, UK
| | - Evelyn N Gitau
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Research Coast, Kilifi, Kenya.,Alliance for Accelerating Excellence in Science in Africa (AESA), Nairobi, Kenya
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Njunge JM, Oyaro IN, Kibinge NK, Rono MK, Kariuki SM, Newton CR, Berkley JA, Gitau EN. Cerebrospinal fluid markers to distinguish bacterial meningitis from cerebral malaria in children. Wellcome Open Res 2017. [DOI: 10.12688/wellcomeopenres.11958.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background. Few hospitals in high malaria endemic countries in Africa have the diagnostic capacity for clinically distinguishing acute bacterial meningitis (ABM) from cerebral malaria (CM). As a result, empirical use of antibiotics is necessary. A biochemical marker of ABM would facilitate precise clinical diagnosis and management of these infections and enable rational use of antibiotics. Methods. We used label-free protein quantification by mass spectrometry to identify cerebrospinal fluid (CSF) markers that distinguish ABM (n=37) from CM (n=22) in Kenyan children. Fold change (FC) and false discovery rates (FDR) were used to identify differentially expressed proteins. Subsequently, potential biomarkers were assessed for their ability to discriminate between ABM and CM using receiver operating characteristic (ROC) curves. Results. The host CSF proteome response to ABM (Haemophilus influenza and Streptococcus pneumoniae) is significantly different to CM. Fifty two proteins were differentially expressed (FDR<0.01, Log FC≥2), of which 83% (43/52) were upregulated in ABM compared to CM. Myeloperoxidase and lactotransferrin were present in 37 (100%) and 36 (97%) of ABM cases, respectively, but absent in CM (n=22). Area under the ROC curve (AUC), sensitivity, and specificity were assessed for myeloperoxidase (1, 1, and 1; 95% CI, 1-1) and lactotransferrin (0.98, 0.97, and 1; 95% CI, 0.96-1). Conclusion. Myeloperoxidase and lactotransferrin have a high potential to distinguish ABM from CM and thereby improve clinical management. Their validation requires a larger cohort of samples that includes other bacterial aetiologies of ABM.
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Akhuemokhan OC, Ewah-Odiase RO, Akpede N, Ehimuan J, Adomeh DI, Odia I, Olomu SC, Pahlmann M, Becker-Ziaja B, Happi CT, Asogun DA, Okogbenin SA, Okokhere PO, Dawodu OS, Omoike IU, Sabeti PC, Günther S, Akpede GO. Prevalence of Lassa Virus Disease (LVD) in Nigerian children with fever or fever and convulsions in an endemic area. PLoS Negl Trop Dis 2017; 11:e0005711. [PMID: 28671959 PMCID: PMC5510890 DOI: 10.1371/journal.pntd.0005711] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 07/14/2017] [Accepted: 06/13/2017] [Indexed: 12/18/2022] Open
Abstract
Background Convulsions with fever in children are a common neurologic emergency in the tropics, and determining the contribution of endemic viral infections can be challenging. In particular, there is a dearth of data on the prevalence and clinical differentiation of Lassa virus disease (LVD) in febrile children in endemic areas of Nigeria, which has multiple lineages of the virus. The aim of this study was to determine the prevalence and presentation of LVD in febrile children with and without convulsions. Methodology/Principal findings This was a prospective study of consecutive febrile children aged ≥1 month– 15 years admitted to the Children’s Emergency Room of Irrua Specialist Teaching Hospital over a period of 1 year. Febrile children with convulsions (Cases) were compared with those without convulsions (Controls). LVD was defined by the presence of a positive Lassa virus RT-PCR test. Rates were compared between groups using χ2 or Fisher’s exact tests and p <0.05 taken as significant. 373 (40.9%) of 913 admissions had fever. Of these, 108/373 (29%) presented with convulsions. The overall prevalence of LVD was 13/373 (3.5%; 95% CI = 1.9%, 5.7%) in febrile admissions, 3/108 (2.8%) in Cases and 10/265 (3.8%) in Controls [(Odds Ratio (95% Confidence Interval) (OR (95% CI)) of LVD in Cases versus Controls = 0.73 (0.2, 2.7)]. Only vomiting (OR (95% CI) = 0.09 (0.01, 0.70)) and bleeding (OR (95% CI) = 39.56 (8.52, 183.7)) were significantly associated with an increased prevalence of LVD. Conclusions/Significance LVD is an important cause of fever, including undifferentiated fever in children in endemic areas, but it is not significantly associated with convulsions associated with fever. Its prevalence, and lack of clinical differentiation on presentation, underscores the importance of a high index of suspicion in diagnosis. Screening of febrile children with undifferentiated fever in endemic areas for LVD could be an important medical and public health control measure. There has, perhaps, been undue focus on malaria as a cause of childhood fever and convulsions, often with delayed/missed diagnosis of other serious prevalent infections, and correspondingly very little published data on the contribution of Lassa virus disease (LVD) in endemic areas. There is also very little published data on the contribution of LVD to childhood morbidity and mortality in Nigeria, a large LVD-endemic country that has in circulation 3 of the 4 currently known lineages of the Lassa virus. This study was carried out to address these gaps. The results should also be of relevance in the formulation of policies for the treatment and control of viral haemorrhagic fevers. The prevalence of LVD was 5.4% among children with clinically undifferentiated fever (n = 243); 3.9% among those with convulsions associated with fever (n = 77) and 6.0% among those with fever but no convulsions (n = 166). The results underscore the importance of LVD as a cause of acute undifferentiated fever. The results also underscore the need of diagnostic testing for LVD in children with acute undifferentiated fever in endemic areas in order to facilitate control, including the prevention of nosocomial transmission.
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Affiliation(s)
- Odigie C. Akhuemokhan
- Department of Paediatrics, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | | | - Nosa Akpede
- Institute of Lassa Fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | - Jacqueline Ehimuan
- Institute of Lassa Fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | - Donatus I. Adomeh
- Institute of Lassa Fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | - Ikpomwonsa Odia
- Institute of Lassa Fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | - Sylvia C. Olomu
- Department of Paediatrics, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | - Meike Pahlmann
- Bernhard-Nocht-Institute for Tropical Medicine, WHO Collaborating Centre for Arboviruses and Hemorrhagic Fever Reference and Research, Department of Virology, Bernhard-Nocht-Str. 74, Hamburg, Germany
| | - Beate Becker-Ziaja
- Bernhard-Nocht-Institute for Tropical Medicine, WHO Collaborating Centre for Arboviruses and Hemorrhagic Fever Reference and Research, Department of Virology, Bernhard-Nocht-Str. 74, Hamburg, Germany
| | - Christian T. Happi
- Malaria Research Laboratory, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria
| | - Danny A. Asogun
- Institute of Lassa Fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | - Sylvanus A. Okogbenin
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | - Peter O. Okokhere
- Department of Medicine, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | - Osagie S. Dawodu
- Department of Paediatrics, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | - Irekpono U. Omoike
- Department of Paediatrics, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
| | - Pardis C. Sabeti
- Department of Organismic Biology, Broad Institute, Harvard University, Cambridge, Massachusetts, United States of America
| | - Stephan Günther
- Bernhard-Nocht-Institute for Tropical Medicine, WHO Collaborating Centre for Arboviruses and Hemorrhagic Fever Reference and Research, Department of Virology, Bernhard-Nocht-Str. 74, Hamburg, Germany
| | - George O. Akpede
- Department of Paediatrics, Faculty of Clinical Sciences, College of Medicine, Ambrose Alli University, Ekpoma, Edo State, Nigeria
- * E-mail:
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Aetiology and Outcomes of Suspected Infections of the Central Nervous System in Children in Mbarara, Uganda. Sci Rep 2017; 7:2728. [PMID: 28578421 PMCID: PMC5457409 DOI: 10.1038/s41598-017-02741-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 04/19/2017] [Indexed: 11/24/2022] Open
Abstract
Infections of the central nervous system (CNS) are severe conditions, leading to neurological sequelae or death. Knowledge of the causative agents is essential to develop guidelines for case management in resource-limited settings. Between August 2009 and October 2012, we conducted a prospective descriptive study of the aetiology of suspected CNS infections in children two months to 12 years old, with fever and at least one sign of CNS involvement in Mbarara Hospital, Uganda. Children were clinically evaluated on admission and discharge, and followed-up for 6 months for neurological sequelae. Pathogens were identified from cerebrospinal fluid (CSF) and blood using microbiological and molecular methods. We enrolled 459 children. Plasmodium falciparum (36.2%) and bacteria in CSF (13.3%) or blood (3.3%) were the most detected pathogens. Viruses were found in 27 (5.9%) children. No pathogen was isolated in 207 (45.1%) children. Patterns varied by age and HIV status. Eighty-three (18.1%) children died during hospitalisation, and 23 (5.0%) during follow-up. Forty-one (13.5%) children had neurological sequelae at the last visit. While malaria remains the main aetiology in children with suspected CNS infections, no pathogen was isolated in many children. The high mortality and high rate of neurological sequelae highlight the need for efficient diagnosis.
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von Saint André A, Pavlinac PB, Jacob ST, Zimmerman J, Walson JL. Fluid resuscitation for children with severe febrile illness and septic shock in resource-limited settings. Hippokratia 2016. [DOI: 10.1002/14651858.cd009655.pub2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Amélie von Saint André
- Seattle Children's Hospital; Department of Pediatrics, Devision of Pediatric Critical Care Medicine, International Respiratory and Severe Illness Center (INTERSECT), University of Washington; 4800 Sand Point Way NE Seattle Washington USA 98105
| | | | - Shevin T Jacob
- University of Washington; International Respiratory and Severe Illness Canter (INTERSECT), Department of Medicine; Seattle USA
| | - Jerry Zimmerman
- University of Washington/Seattle Childrens Hospital; Department of Pediatrics; 4800 Sandpoint Way NE Seattle USA 98105
| | - Judd L Walson
- University of Washington; Departments of Global Health, Medicine (Infectious Disease) and Pediatrics, Epidemiology; Box 359909 325 Ninth Avenue Seattle WA USA 98104
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Amboko BI, Ayieko P, Ogero M, Julius T, Irimu G, English M. Malaria investigation and treatment of children admitted to county hospitals in western Kenya. Malar J 2016; 15:506. [PMID: 27756388 PMCID: PMC5069818 DOI: 10.1186/s12936-016-1553-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Accepted: 10/05/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Up to 90 % of the global burden of malaria morbidity and mortality occurs in sub-Saharan Africa and children under-five bear a disproportionately high malaria burden. Effective inpatient case management can reduce severe malaria mortality and morbidity, but there are few reports of how successfully international and national recommendations are adopted in management of inpatient childhood malaria. METHODS A descriptive cross-sectional study of inpatient malaria case management practices was conducted using data collected over 24 months in five hospitals from high malaria risk areas participating in the Clinical Information Network (CIN) in Kenya. This study describes documented clinical features, laboratory investigations and treatment of malaria in children (2-59 months) and adherence to national guidelines. RESULTS A total of 13,014 children had a malaria diagnosis on admission to the five hospitals between March, 2014 and February, 2016. Their median age was 24 months (IQR 12-36 months). The proportion with a diagnostic test for malaria requested was 11,981 (92.1 %). Of 10,388 patients with malaria test results documented, 8050 (77.5 %) were positive and anti-malarials were prescribed in 6745 (83.8 %). Malaria treatment was prescribed in 1613/2338 (69.0 %) children with a negative malaria result out of which only 52 (3.2 %) had a repeat malaria test done as recommended in national guidelines. Documentation of clinical features was good across all hospitals, but quinine remained the most prescribed malaria drug (47.2 % of positive cases) although a transition to artesunate (46.1 %) was observed. Although documented clinical features suggested approximately half of positive malaria patients were not severe cases artemether-lumefantrine was prescribed on admission in only 3.7 % cases. CONCLUSIONS Despite improvements in inpatient malaria care, high rates of presumptive treatment for test negative children and likely over-use of injectable anti-malarial drugs were observed. Three years after national policy change, there is a gradual transition to artesunate. Continued efforts to support improved routine inpatient malaria care through dissemination and implementation of guidelines, and access to recommended drugs are needed together with improved capacity of hospitals to investigate other causes of severe illness in children. Efforts to improve clinical information could help track progress.
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Affiliation(s)
- Beatrice I. Amboko
- Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, Nairobi, 00100 Kenya
| | - Philip Ayieko
- Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, Nairobi, 00100 Kenya
| | - Morris Ogero
- Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, Nairobi, 00100 Kenya
| | - Thomas Julius
- Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, Nairobi, 00100 Kenya
| | - Grace Irimu
- Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, Nairobi, 00100 Kenya
- Department of Paediatrics and Child Health, University of Nairobi, Nairobi, Kenya
| | - Mike English
- Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, Nairobi, 00100 Kenya
- Nuffield Department of Medicine, Oxford University, Oxford, UK
| | - on behalf of Clinical Information Network authors
- Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, Nairobi, 00100 Kenya
- Department of Paediatrics and Child Health, University of Nairobi, Nairobi, Kenya
- Nuffield Department of Medicine, Oxford University, Oxford, UK
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Establishment of a murine model of cerebral malaria in KunMing mice infected with Plasmodium berghei ANKA. Parasitology 2016; 143:1672-80. [PMID: 27574013 DOI: 10.1017/s0031182016001475] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Malaria remains one of the most devastating diseases. Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection resulting in high mortality and morbidity worldwide. Analysis of precise mechanisms of CM in humans is difficult for ethical reasons and animal models of CM have been employed to study malaria pathogenesis. Here, we describe a new experimental cerebral malaria (ECM) model with Plasmodium berghei ANKA infection in KunMing (KM) mice. KM mice developed ECM after blood-stage or sporozoites infection, and the development of ECM in KM mice has a dose-dependent relationship with sporozoites inoculums. Histopathological findings revealed important features associated with ECM, including accumulation of mononuclear cells and red blood cells in brain microvascular, and brain parenchymal haemorrhages. Blood-brain barrier (BBB) examination showed that BBB disruption was present in infected KM mice when displaying clinical signs of CM. In vivo bioluminescent imaging experiment indicated that parasitized red blood cells accumulated in most vital organs including heart, lung, spleen, kidney, liver and brain. The levels of inflammatory cytokines interferon-gamma, tumour necrosis factor-alpha, interleukin (IL)-17, IL-12, IL-6 and IL-10 were all remarkably increased in KM mice infected with P. berghei ANKA. This study indicates that P. berghei ANKA infection in KM mice can be used as ECM model to extend further research on genetic, pharmacological and vaccine studies of CM.
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Free Sialic Acid Acts as a Signal That Promotes Streptococcus pneumoniae Invasion of Nasal Tissue and Nonhematogenous Invasion of the Central Nervous System. Infect Immun 2016; 84:2607-15. [PMID: 27354445 DOI: 10.1128/iai.01514-15] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 06/18/2016] [Indexed: 11/20/2022] Open
Abstract
Streptococcus pneumoniae (pneumococcus) is a leading cause of bacterial meningitis and neurological sequelae in children worldwide. Acute bacterial meningitis is widely considered to result from bacteremia that leads to blood-brain barrier breakdown and bacterial dissemination throughout the central nervous system (CNS). Previously, we showed that pneumococci can gain access to the CNS through a nonhematogenous route without peripheral blood infection. This access is thought to occur when the pneumococci in the upper sinus follow the olfactory nerves and enter the CNS through the olfactory bulbs. In this study, we determined whether the addition of exogenous sialic acid postcolonization promotes nonhematogenous invasion of the CNS. Previously, others showed that treatment with exogenous sialic acid post-pneumococcal infection increased the numbers of CFU recovered from an intranasal mouse model of infection. Using a pneumococcal colonization model, an in vivo imaging system, and a multiplex assay for cytokine expression, we demonstrated that sialic acid can increase the number of pneumococci recovered from the olfactory bulbs and brains of infected animals. We also show that pneumococci primarily localize to the olfactory bulb, leading to increased expression levels of proinflammatory cytokines and chemokines. These findings provide evidence that sialic acid can enhance the ability of pneumococci to disseminate into the CNS and provide details about the environment needed to establish nonhematogenous pneumococcal meningitis.
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Abstract
Falciparum malaria is the most common cause of convulsions in children admitted to hospital in malaria endemic areas. Detection of convulsions requires close monitoring and one should be on the look out for signs of subtle convulsions. About a third of acute seizures in children with cerebral malaria, do not manifest as convulsions, but as changes in eye deviation, salivation and/or eye deviation. It is important to terminate convulsions lasting more than 5 min, since prolonged convulsions are associated with neurological deficits in survivors of children with severe malaria. Initial management should include putting the child into the left lateral position, checking the blood glucose and administering oxygen if hypoxic. The benzodiazepines, particularly diazepam, are used as the initial anticonvulsants. Phénobarbital and Phenytoin are used as second-line treatments. Prompt and effective management of falciparum malaria associated convulsions may contribute to a better outcome in children with severe malaria.
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Affiliation(s)
- B R Ogutu
- Walter Reed Project-Centre for Clinical Research, Kenya Medical Research Institute [KEMRI], PO Box 54, Kisumu.
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Rubio M, Bassat Q, Estivill X, Mayor A. Tying malaria and microRNAs: from the biology to future diagnostic perspectives. Malar J 2016; 15:167. [PMID: 26979504 PMCID: PMC4793504 DOI: 10.1186/s12936-016-1222-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 03/09/2016] [Indexed: 12/21/2022] Open
Abstract
Symptoms caused by bacterial, viral and malarial infections usually overlap and aetiologic diagnosis is difficult. Patient management in low-resource countries with limited laboratory services has been based predominantly on clinical evaluation and syndromic approaches. However, such clinical assessment has limited accuracy both for identifying the likely aetiological cause and for the early recognition of patients who will progress to serious or fatal disease. Plasma-detectable biomarkers that rapidly and accurately diagnose severe infectious diseases could reduce morbidity and decrease the unnecessary use of usually scarce therapeutic drugs. The discovery of microRNAs (miRNAs) has opened exciting new avenues to identify blood biomarkers of organ-specific injury. This review assesses current knowledge on the relationship between malaria disease and miRNAs, and evaluates how future research might lead to the use of these small molecules for identifying patients with severe malaria disease and facilitate treatment decisions.
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Affiliation(s)
- Mercedes Rubio
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK building), 08036, Barcelona, Spain
| | - Quique Bassat
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK building), 08036, Barcelona, Spain.,Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique
| | - Xavier Estivill
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology; CIBER in Epidemiology and Public Health (CIBERESP), Universitat Pompeu Fabra (UPF), Barcelona, Spain.,Experimental Genetics, Sidra Medical and Research Centre, Doha, Qatar
| | - Alfredo Mayor
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Carrer Rosselló 153 (CEK building), 08036, Barcelona, Spain. .,Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique.
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Global selection of Plasmodium falciparum virulence antigen expression by host antibodies. Sci Rep 2016; 6:19882. [PMID: 26804201 PMCID: PMC4726288 DOI: 10.1038/srep19882] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 12/21/2015] [Indexed: 12/22/2022] Open
Abstract
Parasite proteins called PfEMP1 that are inserted on the surface of infected erythrocytes, play a key role in the severe pathology associated with infection by the Plasmodium falciparum malaria parasite. These proteins mediate binding of infected cells to the endothelial lining of blood vessels as a strategy to avoid clearance by the spleen and are major targets of naturally acquired immunity. PfEMP1 is encoded by a large multi-gene family called var. Mutually-exclusive transcriptional switching between var genes allows parasites to escape host antibodies. This study examined in detail the patterns of expression of var in a well-characterized sample of parasites from Kenyan Children. Instead of observing clear inverse relationships between the expression of broad sub-classes of PfEMP1, we found that expression of different PfEMP1 groups vary relatively independently. Parasite adaptation to host antibodies also appears to involve a general reduction in detectable var gene expression. We suggest that parasites switch both between different PfEMP1 variants and between high and low expression states. Such a strategy could provide a means of avoiding immunological detection and promoting survival under high levels of host immunity.
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Mallewa M, Vallely P, Faragher B, Banda D, Klapper P, Mukaka M, Khofi H, Pensulo P, Taylor T, Molyneux M, Solomon T. Viral CNS infections in children from a malaria-endemic area of Malawi: a prospective cohort study. LANCET GLOBAL HEALTH 2015; 1:e153-60. [PMID: 24748325 PMCID: PMC3986031 DOI: 10.1016/s2214-109x(13)70060-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
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.
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Abstract
BACKGROUND Acute bacterial meningitis (ABM) remains a significant cause of pediatric illness and death in low and middle income countries. Identifying severity risk factors and predictive scores may guide interventions to reduce poor outcomes. METHODS Data from a prospective surveillance study for ABM in children aged 0-59 months admitted to 3 referral hospitals in Guatemala City from 2000 to 2007 were analyzed. ABM was defined as positive cerebrospinal fluid (CSF) culture, positive latex agglutination or CSF white blood cell greater than 100 cells/mL. Univariate and multivariate analyses of risk factors at hospital admission that predicted major morbidity or death during hospitalization were performed, along with validation of the predictive Herson-Todd score (HTS). RESULTS Of 809 children with ABM episodes, 221 (27.3%) survived with major morbidity and 192 (23.7%) died. Among 383 children with nonmissing data, the most significant multivariate predictors for death or major morbidity were seizure [odds ratio (OR), 101.5; P < 0.001], CSF glucose less than 20 mg/dL (OR, 5.3; P = 0.0004), symptom duration more than 3 days (OR, 3.7; P = 0.003) and coma (OR, 6.3; P = 0.004). Of 221 children with a HTS greater than 5, 204 (92%) died or suffered major morbidity (OR, 10.3; P < 0.0001). CONCLUSION ABM is a cause of considerable morbidity and mortality in Guatemala. Several clinical risk factors and the composite HTS predicted death or major morbidity. These predictors could help clinicians in low and middle income country guide medical care for ABM and could contribute to the public health impact assessment in preventing meningitis with vaccines.
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Muro F, Reyburn R, Reyburn H. Acute respiratory infection and bacteraemia as causes of non-malarial febrile illness in African children: a narrative review. Pneumonia (Nathan) 2015; 6:6-17. [PMID: 26594615 PMCID: PMC4650196 DOI: 10.15172/pneu.2015.6/488] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 03/13/2015] [Indexed: 12/16/2022] Open
Abstract
The replacement of "presumptive treatment for malaria" by "test before treat" strategies for the management of febrile illness is raising awareness of the importance of knowing more about the causes of illness in children who are suspected to have malaria but return a negative parasitological test. The most common cause of non-malarial febrile illness (NMFI) in African children is respiratory tract infection. Whilst the bacterial causes of NMFI are well known, the increasing use of sensitive techniques such as polymerase chain reaction (PCR) tests is revealing large numbers of viruses that are potential respiratory pathogens. However, many of these organisms are commonly present in the respiratory tract of healthy children so causality and risk factors for pneumonia remain poorly understood. Infection with a combination of viral and bacterial pathogens is increasingly recognised as important in the pathogenesis of pneumonia. Similarly, blood stream infections with organisms typically grown by aerobic culture are well known but a growing number of organisms that can be identified only by PCR, viral culture, or serology are now recognised to be common pathogens in African children. The high mortality of hospitalised children on the first or second day of admission suggests that, unless results are rapidly available, diagnostic tests to identify specific causes of illness will still be of limited use in guiding the potentially life saving decisions relating to initial treatment of children admitted to district hospitals in Africa with severe febrile illness and a negative test for malaria. Malaria control and the introduction of vaccines against Haemophilus influenzae type b and pneumococcal disease are contributing to improved child survival in Africa. However, increased parasitological testing for malaria is associated with increased use of antibiotics to which resistance is already high.
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Affiliation(s)
- Florid Muro
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Rita Reyburn
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Parkville, Victoria Australia
- New Vaccine Evaluation Project, Colonial War Memorial Hospital, Suva, Fiji
| | - Hugh Reyburn
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel St London, WICE7HT UK
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Etiopathogenesis and Pathophysiology of Malaria. HUMAN AND MOSQUITO LYSOZYMES 2015. [PMCID: PMC7123976 DOI: 10.1007/978-3-319-09432-8_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Malaria is a parasitic disease caused by Plasmodium protozoan parasites and transmitted by Anopheles mosquitoes. The disease is diffused in tropical areas, where it is associated with high morbidity and mortality. P. falciparum is the most dangerous species, mainly affecting young children. The parasite cycle occurs both in humans (asexual stages) and in mosquitoes (sexual stages). In humans, Plasmodium grows and multiplies within red blood cells using hemoglobin as essential source of nutrients and energy. However, this process generates toxic heme that the parasite aggregates into an insoluble inert biocrystal called hemozoin. This molecule sequesters in various organs (liver, spleen, and brain), potentially contributing to the development of malaria immunopathogenesis. Uncomplicated falciparum malaria clinical frame ranges from asymptomatic infection to classic symptoms such as fever, chills, sweating, headache, and muscle aches. However, malaria can also evolve into severe life-threatening complications, including cerebral malaria, severe anemia, respiratory distress, and acute renal failure.
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Douglas NM, Pontororing GJ, Lampah DA, Yeo TW, Kenangalem E, Poespoprodjo JR, Ralph AP, Bangs MJ, Sugiarto P, Anstey NM, Price RN. Mortality attributable to Plasmodium vivax malaria: a clinical audit from Papua, Indonesia. BMC Med 2014; 12:217. [PMID: 25406857 PMCID: PMC4264333 DOI: 10.1186/s12916-014-0217-z] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/22/2014] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Plasmodium vivax causes almost half of all malaria cases in Asia and is recognised as a significant cause of morbidity. In recent years it has been associated with severe and fatal disease. The extent to which P. vivax contributes to death is not known. METHODS To define the epidemiology of mortality attributable to vivax malaria in southern Papua, Indonesia, a retrospective clinical records-based audit was conducted of all deaths in patients with vivax malaria at a tertiary referral hospital. RESULTS Between January 2004 and September 2009, hospital surveillance identified 3,495 inpatients with P. vivax monoinfection and 65 (1.9%) patients who subsequently died. Charts for 54 of these 65 patients could be reviewed, 40 (74%) of whom had pure P. vivax infections on cross-checking. Using pre-defined conservative criteria, vivax malaria was the primary cause of death in 6 cases, a major contributor in 17 cases and a minor contributor in a further 13 cases. Extreme anaemia was the most common primary cause of death. Malnutrition, sepsis with respiratory and gastrointestinal manifestations, and chronic diseases were the commonest attributed causes of death for patients in the latter two categories. There were an estimated 293,763 cases of pure P. vivax infection in the community during the study period giving an overall minimum case fatality of 0.12 per 1,000 infections. The corresponding case fatality in hospitalised patients was 10.3 per 1,000 infections. CONCLUSIONS Although uncommonly directly fatal, vivax malaria is an important indirect cause of death in southern Papua in patients with malnutrition, sepsis syndrome and chronic diseases, including HIV infection.
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Affiliation(s)
- Nicholas M Douglas
- Global Health Division, Menzies School of Health Research and Charles Darwin University, PO Box 41096, Casuarina, Darwin, NT 0811, Australia. .,Centre for Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
| | - Gysje J Pontororing
- Papuan Health and Community Development Foundation, Timika, Papua, Indonesia.
| | - Daniel A Lampah
- Papuan Health and Community Development Foundation, Timika, Papua, Indonesia.
| | - Tsin W Yeo
- Global Health Division, Menzies School of Health Research and Charles Darwin University, PO Box 41096, Casuarina, Darwin, NT 0811, Australia.
| | - Enny Kenangalem
- Papuan Health and Community Development Foundation, Timika, Papua, Indonesia. .,District Health Authority, Timika, Papua, Indonesia.
| | - Jeanne Rini Poespoprodjo
- Papuan Health and Community Development Foundation, Timika, Papua, Indonesia. .,District Health Authority, Timika, Papua, Indonesia. .,Department of Paediatrics, Faculty of Medicine, Gadjah Mada University, Yogyakarta, Indonesia.
| | - Anna P Ralph
- Global Health Division, Menzies School of Health Research and Charles Darwin University, PO Box 41096, Casuarina, Darwin, NT 0811, Australia. .,Division of Medicine, Royal Darwin Hospital, Darwin, Australia.
| | - Michael J Bangs
- Public Health & Malaria Control Department, International SOS, PT Freeport Indonesia, Kuala Kencana, Papua, Indonesia. .,Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, 10900, Thailand.
| | | | - Nicholas M Anstey
- Global Health Division, Menzies School of Health Research and Charles Darwin University, PO Box 41096, Casuarina, Darwin, NT 0811, Australia. .,Division of Medicine, Royal Darwin Hospital, Darwin, Australia.
| | - Ric N Price
- Global Health Division, Menzies School of Health Research and Charles Darwin University, PO Box 41096, Casuarina, Darwin, NT 0811, Australia. .,Centre for Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
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Manning L, Laman M, Mare T, Hwaiwhanje I, Siba P, Davis TME. Accuracy of cerebrospinal leucocyte count, protein and culture for the diagnosis of acute bacterial meningitis: a comparative study using Bayesian latent class analysis. Trop Med Int Health 2014; 19:1520-4. [PMID: 25315120 DOI: 10.1111/tmi.12400] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To examine the utility of laboratory methods other than bacterial culture in diagnosing acute bacterial meningitis (ABM). METHODS Bayesian latent class analysis was used to estimate diagnostic precision of cerebrospinal fluid (CSF) culture, leucocyte counts and protein concentrations for ABM in Melanesian children. RESULTS With a cut-off of ≥20 leucocytes/mm(3) , the area under the receiver operating characteristic curve (AUC ROC) was >97.5% for leucocyte counts. A lower (93%) AUC ROC was observed for CSF protein concentrations ≥1 g/l. CSF culture had poor sensitivity and high specificity. CONCLUSION Leucocyte counts provide sufficient diagnostic precision to aid clinical decision-making in ABM.
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Affiliation(s)
- Laurens Manning
- School of Medicine and Pharmacology, Fremantle Hospital, University of Western Australia, Fremantle, WA, Australia
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Aipit J, Laman M, Hwaiwhanje I, Bona C, Pomat N, Siba P, Davis TME, Manning L. Accuracy of initial clinical diagnosis of acute bacterial meningitis in children from a malaria-endemic area of Papua New Guinea. Trans R Soc Trop Med Hyg 2014; 108:444-8. [PMID: 24794922 DOI: 10.1093/trstmh/tru067] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The diagnosis of acute bacterial meningitis (ABM) is challenging in resource-limited settings where cerebral malaria and viral encephalitis are also common. METHODS To assess the accuracy of an initial clinical diagnosis of ABM in a malaria-endemic area of Papua New Guinea (PNG), a retrospective chart review of hospitalized children aged 2 months to 10 years was conducted. RESULTS Of the 481 eligible children, 240 had an initial clinical diagnosis of ABM that was confirmed independently by trained research staff under standardized conditions, with laboratory support in only 84 (17.5%; 84/481). When compared with the final laboratory-confirmed diagnosis, an initial diagnosis of ABM had a sensitivity, specificity, positive predictive value and negative predictive value of 76% (95% CI 66-85%), 56% (95% CI 51-61%), 27% (95% CI 21-33) and 92% (95% CI 87-95%), respectively. There was discordance between initial and final diagnosis of ABM in 196 children; 176 initially considered to have ABM had an alternative diagnosis, while 20 without an initial diagnosis of ABM were confirmed to have ABM. CONCLUSION These data show that initial misdiagnosis of ABM is common in a malaria-endemic area of PNG. A diagnostic algorithm using standardized assessment for meningeal irritation, coma and malaria parasitological testing needs further evaluation in this setting.
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Affiliation(s)
- Jimmy Aipit
- Modilon General Hospital, Paediatrics Unit, Madang, Papua New Guinea
| | - Moses Laman
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, Fremantle, Western Australia, Australia
| | - Ilomo Hwaiwhanje
- Modilon General Hospital, Paediatrics Unit, Madang, Papua New Guinea
| | - Cathy Bona
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Naomi Pomat
- Modilon General Hospital, Paediatrics Unit, Madang, Papua New Guinea
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Timothy M E Davis
- School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, Fremantle, Western Australia, Australia
| | - Laurens Manning
- School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, Fremantle, Western Australia, Australia
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Abdi AI, Fegan G, Muthui M, Kiragu E, Musyoki JN, Opiyo M, Marsh K, Warimwe GM, Bull PC. Plasmodium falciparum antigenic variation: relationships between widespread endothelial activation, parasite PfEMP1 expression and severe malaria. BMC Infect Dis 2014; 14:170. [PMID: 24674301 PMCID: PMC3986854 DOI: 10.1186/1471-2334-14-170] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 03/19/2014] [Indexed: 12/01/2022] Open
Abstract
Background Plasmodium falciparum erythrocyte membrane protein 1(PfEMP1) is a family of variant surface antigens (VSA) that mediate the adhesion of parasite infected erythrocytes to capillary endothelial cells within host tissues. Opinion is divided over the role of PfEMP1 in the widespread endothelial activation associated with severe malaria. In a previous study we found evidence for differential associations between defined VSA subsets and specific syndromes of severe malaria: group A-like PfEMP1 expression and the “rosetting” phenotype were associated with impaired consciousness and respiratory distress, respectively. This study explores the involvement of widespread endothelial activation in these associations. Methods We used plasma angiopoietin-2 as a marker of widespread endothelial activation. Using logistic regression analysis, we explored the relationships between plasma angiopoietin-2 levels, parasite VSA expression and the two syndromes of severe malaria, impaired consciousness and respiratory distress. Results Plasma angiopoietin-2 was associated with both syndromes. The rosetting phenotype did not show an independent association with respiratory distress when adjusted for angiopoietin-2, consistent with a single pathogenic mechanism involving widespread endothelial activation. In contrast, group A-like PfEMP1 expression and angiopoietin-2 maintained independent associations with impaired consciousness when adjusted for each other. Conclusion The results are consistent with multiple pathogenic mechanisms leading to severe malaria and heterogeneity in the pathophysiology of impaired consciousness. The observed association between group A-like PfEMP1 and impaired consciousness does not appear to involve widespread endothelial activation.
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Affiliation(s)
- Abdirahman I Abdi
- KEMRI-Wellcome Trust Research Programme, P,O, Box 230-80108, Kilifi, Kenya.
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Abstract
BACKGROUND Hearing loss from childhood bacterial meningitis is believed to develop early and have little tendency for recovery. We performed serial hearing evaluations in a large number of children with bacterial meningitis in Luanda, Angola to clarify if, and how often, the result changed. METHODS Children with confirmed bacterial meningitis and hearing evaluations on admission, day 7 of treatment and the follow-up visit formed the study group. Hearing was tested by auditory brainstem response audiometry using stimuli of 40 dB, 60 dB and 80 dB. Threshold changes are described between the composite levels of 40/60 dB and 80/>80 dB. RESULTS In all, 235 ears were tested. While the ≤ 60 dB and ≥ 80 dB levels were maintained through all 3 examinations in 54% and 5% of ears, respectively, changes occurred in 41%. Deterioration from the ≤ 60 dB level to ≥ 80 dB was found in 10% of the ears transiently and in 7% permanently. Improvement from the ≥ 80 dB level to ≤ 60 dB occurred in 22% of the ears. Half of the ears with ≥ 80 dB impairment at the follow-up visit arrived with this finding; the others lost hearing later. Maintaining the ≤ 60 dB level throughout was associated with milder disease (P = 0.003), fewer convulsions (P < 0.0001) and older age (P = 0.009). CONCLUSIONS Almost half of the ears showed threshold changes after admission during recovery from bacterial meningitis, most frequently improvement of initially severely impaired hearing, but some normal ears or with moderate impairment became severely impaired.
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Invasive bacterial co-infection in African children with Plasmodium falciparum malaria: a systematic review. BMC Med 2014; 12:31. [PMID: 24548672 PMCID: PMC3928319 DOI: 10.1186/1741-7015-12-31] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 01/21/2014] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Severe malaria remains a major cause of pediatric hospital admission across Africa. Invasive bacterial infection (IBI) is a recognized complication of Plasmodium falciparum malaria, resulting in a substantially worse outcome. Whether a biological relationship exists between malaria infection and IBI susceptibility remains unclear. We, therefore, examined the extent, nature and evidence of this association. METHODS We conducted a systematic search in August 2012 of three major scientific databases, PubMed, Embase and Africa Wide Information, for articles describing bacterial infection among children with P. falciparum malaria using the search string '(malaria OR plasmodium) AND (bacteria OR bacterial OR bacteremia OR bacteraemia OR sepsis OR septicaemia OR septicemia).' Eligiblity criteria also included studies of children hospitalized with malaria or outpatient attendances in sub-Saharan Africa. RESULTS A total of 25 studies across 11 African countries fulfilled our criteria. They comprised twenty cohort analyses, two randomized controlled trials and three prospective epidemiological studies. In the meta-analysis of 7,208 children with severe malaria the mean prevalence of IBI was 6.4% (95% confidence interval (CI) 5.81 to 6.98%). In a further meta-analysis of 20,889 children hospitalised with all-severity malaria and 27,641 children with non-malarial febrile illness the mean prevalence of IBI was 5.58 (95% CI 5.5 to 5.66%) in children with malaria and 7.77% (95% CI 7.72 to 7.83%) in non-malaria illness. Ten studies reported mortality stratified by IBI. Case fatality was higher at 81 of 336, 24.1% (95% CI 18.9 to 29.4) in children with malaria/IBI co-infection compared to 585 of 5,760, 10.2% (95% CI 9.3 to 10.98) with malaria alone. Enteric gram-negative organisms were over-represented in malaria cases, non-typhoidal Salmonellae being the most commonest isolate. There was weak evidence indicating IBI was more common in the severe anemia manifestation of severe malaria. CONCLUSIONS The accumulated evidence suggests that children with recent or acute malaria are at risk of bacterial infection, which results in an increased risk of mortality. Characterising the exact nature of this association is challenging due to the paucity of appropriate severity-matched controls and the heterogeneous data. Further research to define those at greatest risk is necessary to target antimicrobial treatment.
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Polimeni M, Prato M. Host matrix metalloproteinases in cerebral malaria: new kids on the block against blood-brain barrier integrity? Fluids Barriers CNS 2014; 11:1. [PMID: 24467887 PMCID: PMC3905658 DOI: 10.1186/2045-8118-11-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 01/24/2014] [Indexed: 12/23/2022] Open
Abstract
Cerebral malaria (CM) is a life-threatening complication of falciparum malaria, associated with high mortality rates, as well as neurological impairment in surviving patients. Despite disease severity, the etiology of CM remains elusive. Interestingly, although the Plasmodium parasite is sequestered in cerebral microvessels, it does not enter the brain parenchyma: so how does Plasmodium induce neuronal dysfunction? Several independent research groups have suggested a mechanism in which increased blood–brain barrier (BBB) permeability might allow toxic molecules from the parasite or the host to enter the brain. However, the reported severity of BBB damage in CM is variable depending on the model system, ranging from mild impairment to full BBB breakdown. Moreover, the factors responsible for increased BBB permeability are still unknown. Here we review the prevailing theories on CM pathophysiology and discuss new evidence from animal and human CM models implicating BBB damage. Finally, we will review the newly-described role of matrix metalloproteinases (MMPs) and BBB integrity. MMPs comprise a family of proteolytic enzymes involved in modulating inflammatory response, disrupting tight junctions, and degrading sub-endothelial basal lamina. As such, MMPs represent potential innovative drug targets for CM.
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Affiliation(s)
| | - Mauro Prato
- Dipartimento di Neuroscienze, Università di Torino, C,so Raffaello 30, 10125 Torino, Italy.
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Laman M, Manning L, Siba PM, Davis TME. Prevalence and implications of cerebrospinal fluid leukocytosis in Papua New Guinean children hospitalized with severe malaria. Am J Trop Med Hyg 2013; 89:866-8. [PMID: 24019433 DOI: 10.4269/ajtmh.13-0281] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Cerebrospinal fluid (CSF) leukocytosis in severe malaria was assessed in 87 children in Papua New Guinea participating in a detailed longitudinal observational study who had undergone lumbar puncture for further investigation of altered consciousness and/or convulsions. After rigorous exclusion of non-malarial infection, 16 (20.5%) of 78 children with Plasmodium falciparum monoinfection but 0 of 9 with P. vivax/mixed-species malaria had a detectable CSF leukocytosis, which was unrelated to prior, including complex, seizures. There were eight children with a CSF leukocyte density > 10 cells/μL (9.2% of the total sample), half of whom had cerebral malaria (4 of 22, 18.1%). Cerebrospinal fluid leukocytosis is infrequent in severe pediatric malaria, especially in children with P. vivax infections, and it is generally mild. Its presence in a blood slide-positive child should prompt consideration of alternative diagnoses and empiric antibiotic therapy.
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Affiliation(s)
- Moses Laman
- School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, Freemantle, Western Australia, Australia; Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
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Gwer S, Chacha C, Newton CR, Idro R. Childhood acute non-traumatic coma: aetiology and challenges in management in resource-poor countries of Africa and Asia. Paediatr Int Child Health 2013; 33:129-38. [PMID: 23930724 DOI: 10.1179/2046905513y.0000000068] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE This review examines the best available evidence on the aetiology of childhood acute non-traumatic coma in resource-poor countries (RPCs), discusses the challenges associated with management, and explores strategies to address them. METHODS Publications in English and French which reported on studies on the aetiology of childhood non-traumatic coma in RPCs are reviewed. Primarily, the MEDLINE database was searched using the keywords coma, unconsciousness, causality, aetiology, child, malaria cerebral, meningitis, encephalitis, Africa, Asia, and developing countries. RESULTS 14 records were identified for inclusion in the review. Cerebral malaria (CM) was the commonest cause of childhood coma in most of the studies conducted in Africa. Acute bacterial meningitis (ABM) was the second most common known cause of coma in seven of the African studies. Of the studies in Asia, encephalitides were the commonest cause of coma in two studies in India, and ABM was the commonest cause of coma in Pakistan. Streptococcus pneumoniae was the most commonly isolated organism in ABM. Japanese encephalitis, dengue fever and enteroviruses were the viral agents most commonly isolated. CONCLUSION Accurate diagnosis of the aetiology of childhood coma in RPCs is complicated by overlap in clinical presentation, limited diagnostic resources, disease endemicity and co-morbidity. For improved outcomes, studies are needed to further elucidate the aetiology of childhood coma in RPCs, explore simple and practical diagnostic tools, and investigate the most appropriate specific and supportive interventions to manage and prevent infectious encephalopathies.
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Affiliation(s)
- Samson Gwer
- Department of Medical Physiology, Kenyatta University, Kenya.
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Gitau EN, Kokwaro GO, Karanja H, Newton CRJC, Ward SA. Plasma and cerebrospinal proteomes from children with cerebral malaria differ from those of children with other encephalopathies. J Infect Dis 2013; 208:1494-503. [PMID: 23888081 PMCID: PMC3789566 DOI: 10.1093/infdis/jit334] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Clinical signs and symptoms of cerebral malaria in children are nonspecific and are seen in other common encephalopathies in malaria-endemic areas. This makes accurate diagnosis difficult in resource-poor settings. Novel malaria-specific diagnostic and prognostic methods are needed. We have used 2 proteomic strategies to identify differentially expressed proteins in plasma and cerebrospinal fluid from children with a diagnosis of cerebral malaria, compared with those with a diagnosis of malaria-slide-negative acute bacterial meningitis and other nonspecific encephalopathies. Here we report the presence of differentially expressed proteins in cerebral malaria in both plasma and cerebrospinal fluid that could be used to better understand pathogenesis and help develop more-specific diagnostic methods. In particular, we report the expression of 2 spectrin proteins that have known Plasmodium falciparum–binding partners involved in the stability of the infected red blood cell, suppressing further invasion and possibly enhancing the red blood cell's ability to sequester in microvasculature.
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Affiliation(s)
- Evelyn N Gitau
- Centre for Geographic Medicine-Coast, KEMRI-Wellcome Trust Research Programme, Kilifi
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Lundblom K, Murungi L, Nyaga V, Olsson D, Rono J, Osier F, Ogada E, Montgomery S, Scott JAG, Marsh K, Färnert A. Plasmodium falciparum infection patterns since birth and risk of severe malaria: a nested case-control study in children on the coast of Kenya. PLoS One 2013; 8:e56032. [PMID: 23418502 PMCID: PMC3572150 DOI: 10.1371/journal.pone.0056032] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 01/04/2013] [Indexed: 01/27/2023] Open
Abstract
Children in malaria endemic areas acquire immunity to severe malaria faster than to mild malaria. Only a minority of children suffers from severe malaria and it is not known what determines this. The aim of this study was to establish how P. falciparum infections during the first years of life affect the risk of severe malaria. A matched case-control study was nested within a large birth cohort set up to study the immunoepidemiology of pneumococci on the Kenyan coast. Infection patterns in three-monthly blood samples in cohort children admitted to hospital with severe malaria were compared to controls matched on age, residential location and time of sampling. P. falciparum detected at least once from birth conferred an increased risk of severe malaria and particularly if multiclonal infections, as characterized by genotyping of a polymorphic antigen gene, were ever detected. The results show for the first time that children with severe malaria have more infections early in life compared to community controls. These findings provide important insights on the immunity to severe disease, knowledge essential for the development of a vaccine against severe malaria.
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Affiliation(s)
- Klara Lundblom
- Unit of Infectious Diseases, Department of Medicine Solna, Karolinska Institute, Stockholm, Sweden.
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Hendriksen ICE, White LJ, Veenemans J, Mtove G, Woodrow C, Amos B, Saiwaew S, Gesase S, Nadjm B, Silamut K, Joseph S, Chotivanich K, Day NPJ, von Seidlein L, Verhoef H, Reyburn H, White NJ, Dondorp AM. Defining falciparum-malaria-attributable severe febrile illness in moderate-to-high transmission settings on the basis of plasma PfHRP2 concentration. J Infect Dis 2013; 207:351-61. [PMID: 23136222 PMCID: PMC3532834 DOI: 10.1093/infdis/jis675] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 08/23/2012] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND In malaria-endemic settings, asymptomatic parasitemia complicates the diagnosis of malaria. Histidine-rich protein 2 (HRP2) is produced by Plasmodium falciparum, and its plasma concentration reflects the total body parasite burden. We aimed to define the malaria-attributable fraction of severe febrile illness, using the distributions of plasma P. falciparum HRP2 (PfHRP2) concentrations from parasitemic children with different clinical presentations. METHODS Plasma samples were collected from and peripheral blood slides prepared for 1435 children aged 6-60 months in communities and a nearby hospital in northeastern Tanzania. The study population included children with severe or uncomplicated malaria, asymptomatic carriers, and healthy control subjects who had negative results of rapid diagnostic tests. The distributions of plasma PfHRP2 concentrations among the different groups were used to model severe malaria-attributable disease. RESULTS The plasma PfHRP2 concentration showed a close correlation with the severity of infection. PfHRP2 concentrations of >1000 ng/mL denoted a malaria-attributable fraction of severe disease of 99% (95% credible interval [CI], 96%-100%), with a sensitivity of 74% (95% CI, 72%-77%), whereas a concentration of <200 ng/mL denoted severe febrile illness of an alternative diagnosis in >10% (95% CI, 3%-27%) of patients. Bacteremia was more common among patients in the lowest and highest PfHRP2 concentration quintiles. CONCLUSIONS The plasma PfHRP2 concentration defines malaria-attributable disease and distinguishes severe malaria from coincidental parasitemia in African children in a moderate-to-high transmission setting.
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Affiliation(s)
- Ilse C E Hendriksen
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
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Hackett MJ, Lee J, El-Assaad F, McQuillan JA, Carter EA, Grau GE, Hunt NH, Lay PA. FTIR imaging of brain tissue reveals crystalline creatine deposits are an ex vivo marker of localized ischemia during murine cerebral malaria: general implications for disease neurochemistry. ACS Chem Neurosci 2012; 3:1017-24. [PMID: 23259037 DOI: 10.1021/cn300093g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 09/11/2012] [Indexed: 12/13/2022] Open
Abstract
Phosphocreatine is a major cellular source of high energy phosphates, which is crucial to maintain cell viability under conditions of impaired metabolic states, such as decreased oxygen and energy availability (i.e., ischemia). Many methods exist for the bulk analysis of phosphocreatine and its dephosphorylated product creatine; however, no method exists to image the distribution of creatine or phosphocreatine at the cellular level. In this study, Fourier transform infrared (FTIR) spectroscopic imaging has revealed the ex vivo development of creatine microdeposits in situ in the brain region most affected by the disease, the cerebellum of cerebral malaria (CM) diseased mice; however, such deposits were also observed at significantly lower levels in the brains of control mice and mice with severe malaria. In addition, the number of deposits was observed to increase in a time-dependent manner during dehydration post tissue cutting. This challenges the hypotheses in recent reports of FTIR spectroscopic imaging where creatine microdeposits found in situ within thin sections from epileptic, Alzheimer's (AD), and amlyoid lateral sclerosis (ALS) diseased brains were proposed to be disease specific markers and/or postulated to contribute to the brain pathogenesis. As such, a detailed investigation was undertaken, which has established that the creatine microdeposits exist as the highly soluble HCl salt or zwitterion and are an ex-vivo tissue processing artifact and, hence, have no effect on disease pathogenesis. They occur as a result of creatine crystallization during dehydration (i.e., air-drying) of thin sections of brain tissue. As ischemia and decreased aerobic (oxidative metabolism) are common to many brain disorders, regions of elevated creatine-to-phosphocreatine ratio are likely to promote crystal formation during tissue dehydration (due to the lower water solubility of creatine relative to phosphocreatine). The results of this study have demonstrated that although the deposits do not occur in vivo, and do not directly play any role in disease pathogenesis, increased levels of creatine deposits within air-dried tissue sections serve as a highly valuable marker for the identification of tissue regions with an altered metabolic status. In this study, the location of crystalline creatine deposits were used to identify whether an altered metabolic state exists within the molecular and granular layers of the cerebellum during CM, which complements the recent discovery of decreased oxygen availability in the brain during this disease.
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Affiliation(s)
- Mark J. Hackett
- School of Chemistry, The University of Sydney, NSW 2006, Australia
| | - Joonsup Lee
- School of Chemistry, The University of Sydney, NSW 2006, Australia
| | | | | | | | | | | | - Peter A. Lay
- School of Chemistry, The University of Sydney, NSW 2006, Australia
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Bisig B, Moreira J, Combes M, Asiimwe A, Bisoffi Z, Haegeman F, Bottieau E, Van den Ende J. Does introduction of thresholds in decision aids benefit the patient?: Comparison between findings-based and threshold-based diagnostic decision aids. Med Decis Making 2012. [PMID: 23204241 DOI: 10.1177/0272989x12461854] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE To assess how different diagnostic decision aids perform in terms of sensitivity, specificity, and harm. METHODS Four diagnostic decision aids were compared, as applied to a simulated patient population: a findings-based algorithm following a linear or branched pathway, a serial threshold-based strategy, and a parallel threshold-based strategy. Headache in immune-compromised HIV patients in a developing country was used as an example. Diagnoses included cryptococcal meningitis, cerebral toxoplasmosis, tuberculous meningitis, bacterial meningitis, and malaria. Data were derived from literature and expert opinion. Diagnostic strategies' validity was assessed in terms of sensitivity, specificity, and harm related to mortality and morbidity. Sensitivity analyses and Monte Carlo simulation were performed. RESULTS The parallel threshold-based approach led to a sensitivity of 92% and a specificity of 65%. Sensitivities of the serial threshold-based approach and the branched and linear algorithms were 47%, 47%, and 74%, respectively, and the specificities were 85%, 95%, and 96%. The parallel threshold-based approach resulted in the least harm, with the serial threshold-based approach, the branched algorithm, and the linear algorithm being associated with 1.56-, 1.44-, and 1.17-times higher harm, respectively. Findings were corroborated by sensitivity and Monte Carlo analyses. CONCLUSION A threshold-based diagnostic approach is designed to find the optimal trade-off that minimizes expected harm, enhancing sensitivity and lowering specificity when appropriate, as in the given example of a symptom pointing to several life-threatening diseases. Findings-based algorithms, in contrast, solely consider clinical observations. A parallel workup, as opposed to a serial workup, additionally allows for all potential diseases to be reviewed, further reducing false negatives. The parallel threshold-based approach might, however, not be as good in other disease settings.
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Affiliation(s)
- Bettina Bisig
- Institute of Tropical Medicine, Antwerp, Belgium (BB, EB)
| | - Juan Moreira
- Institute of Tropical Medicine, Antwerp, Belgium, and Centro de Epidemiologı´a Comunitaria y Medicina Tropical, Esmeraldas, Ecuador (JM)
| | | | - Anita Asiimwe
- Centre Hospitalier Universitaire, Kigali, Rwanda (AA)
| | - Zeno Bisoffi
- Centro per le Malattie Tropicali, Negrar, Verona, Italy (ZB)
| | | | | | - Jef Van den Ende
- Institute of Tropical Medicine, University Hospital, Antwerp, Belgium (JVDE)
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Jallow M, Casals-Pascual C, Ackerman H, Walther B, Walther M, Pinder M, Sisay-Joof F, Usen S, Jallow M, Abubakar I, Olaosebikan R, Jobarteh A, Conway DJ, Bojang K, Kwiatkowski D. Clinical features of severe malaria associated with death: a 13-year observational study in the Gambia. PLoS One 2012; 7:e45645. [PMID: 23029157 PMCID: PMC3460946 DOI: 10.1371/journal.pone.0045645] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 08/21/2012] [Indexed: 11/18/2022] Open
Abstract
Background Severe malaria (SM) is a major cause of death in sub-Saharan Africa. Identification of both specific and sensitive clinical features to predict death is needed to improve clinical management. Methods A 13-year observational study was conducted from 1997 through 2009 of 2,901 children with SM enrolled at the Royal Victoria Teaching Hospital in The Gambia to identify sensitive and specific predictors of poor outcome in Gambian children with severe malaria between the ages 4 months to 14 years. We have measured the sensitivity and specificity of clinical features that predict death or development of neurological sequelae. Findings Impaired consciousness (odds ratio {OR} 4.4 [95% confidence interval {CI}, 2.7–7.3]), respiratory distress (OR 2.4 [95%CI, 1.7–3.2]), hypoglycemia (OR 1.7 [95%CI, 1.2–2.3]), jaundice (OR 1.9 [95%CI, 1.2–2.9]) and renal failure (OR 11.1 [95%CI, 3.3–36.5]) were independently associated with death in children with SM. The clinical features that showed the highest sensitivity and specificity to predict death were respiratory distress (area under the curve 0.63 [95%CI, 0.60–0.65]) and impaired consciousness (AUC 0.61[95%CI, 0.59–0.63]), which were comparable to the ability of hyperlactatemia (blood lactate>5 mM) to predict death (AUC 0.64 [95%CI, 0.55–0.72]). A Blantyre coma score (BCS) of 2 or less had a sensitivity of 74% and specificity of 67% to predict death (AUC 0.70 [95% C.I. 0.68–0.72]), and sensitivity and specificity of 74% and 69%, respectively to predict development of neurological sequelae (AUC 0.72 [95% CI, 0.67–0.76]).The specificity of this BCS threshold to identify children at risk of dying improved in children less than 3 years of age (AUC 0.74, [95% C.I 0.71–0.76]). Conclusion The BCS is a quantitative predictor of death. A BCS of 2 or less is the most sensitive and specific clinical feature to predict death or development of neurological sequelae in children with SM.
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Affiliation(s)
- Muminatou Jallow
- Malaria Programme, MRC Laboratories, Banjul, The Gambia
- Royal Victoria Teaching Hospital, Banjul, The Gambia
| | | | - Hans Ackerman
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | | | - Michael Walther
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | | | | | - Stanley Usen
- Malaria Programme, MRC Laboratories, Banjul, The Gambia
| | | | | | | | | | - David J. Conway
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Kalifa Bojang
- Malaria Programme, MRC Laboratories, Banjul, The Gambia
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Warimwe GM, Fegan G, Musyoki JN, Newton CR, Opiyo M, Githinji G, Andisi C, Menza F, Kitsao B, Marsh K, Bull PC. Prognostic indicators of life-threatening malaria are associated with distinct parasite variant antigen profiles. Sci Transl Med 2012; 4:129ra45. [PMID: 22496547 PMCID: PMC3491874 DOI: 10.1126/scitranslmed.3003247] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PfEMP1 is a family of cytoadhesive surface antigens expressed on erythrocytes infected with Plasmodium falciparum, the parasite that causes the most severe form of malaria. These surface antigens play a role in immune evasion and are thought to contribute to the pathogenesis of the malaria parasite. Previous studies have suggested a role for a specific subset of PfEMP1 called "group A" in severe malaria. To explore the role of group A PfEMP1 in disease, we measured the expression of the var genes that encode them in parasites from clinical isolates collected from children suffering from malaria. We also looked at the ability of these clinical isolates to induce rosetting of erythrocytes, which indicates a cytoadhesion phenotype that is thought to be important in pathogenesis. These two sets of data were correlated with the presence of two life-threatening manifestations of severe malaria in the children: impaired consciousness and respiratory distress. Using regression analysis, we show that marked rosetting was associated with respiratory distress, whereas elevated expression of group A-like var genes without elevated rosetting was associated with impaired consciousness. The results suggest that manifestations of malarial disease may reflect the distribution of cytoadhesion phenotypes expressed by the infecting parasite population.
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Affiliation(s)
- George M. Warimwe
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
| | - Gregory Fegan
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
- Nuffield Department of Clinical Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | - Jennifer N. Musyoki
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
| | - Charles R.J.C. Newton
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
| | - Michael Opiyo
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
| | - George Githinji
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
| | - Cheryl Andisi
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
| | - Francis Menza
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
| | - Barnes Kitsao
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
| | - Kevin Marsh
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
- Nuffield Department of Clinical Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | - Peter C. Bull
- Kenya Medical Research Institute-Wellcome Trust Research Programme, P.O. Box 230-80108 Kilifi, Kenya
- Nuffield Department of Clinical Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
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Laman M, Manning L, Greenhill AR, Mare T, Michael A, Shem S, Vince J, Lagani W, Hwaiwhanje I, Siba PM, Mueller I, Davis TME. Predictors of acute bacterial meningitis in children from a malaria-endemic area of Papua New Guinea. Am J Trop Med Hyg 2012; 86:240-5. [PMID: 22302856 DOI: 10.4269/ajtmh.2012.11-0312] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Predictors of acute bacterial meningitis (ABM) were assessed in 554 children in Papua New Guinea 0.2-10 years of age who were hospitalized with culture-proven meningitis, probable meningitis, or non-meningitic illness investigated by lumbar puncture. Forty-seven (8.5%) had proven meningitis and 36 (6.5%) had probable meningitis. Neck stiffness, Kernig's and Brudzinski's signs and, in children < 18 months of age, a bulging fontanel had positive likelihood ratios (LRs) ≥ 4.3 for proven/probable ABM. Multiple seizures and deep coma were less predictive (LR = 1.5-2.1). Single seizures and malaria parasitemia had low LRs (≤ 0.5). In logistic regression including clinical variables, Kernig's sign and deep coma were positively associated with ABM, and a single seizure was negatively associated (P ≤ 0.01). In models including microscopy, neck stiffness and deep coma were positively associated with ABM and parasitemia was negatively associated with ABM (P ≤ 0.04). In young children, a bulging fontanel added to the model (P < 0.001). Simple clinical features predict ABM in children in Papua New Guinea but malaria microscopy augments diagnostic precision.
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Affiliation(s)
- Moses Laman
- Papua New Guinea Institute of Medical Research, Madang and Goroka, Papua New Guinea.
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Rénia L, Howland SW, Claser C, Charlotte Gruner A, Suwanarusk R, Hui Teo T, Russell B, Ng LFP. Cerebral malaria: mysteries at the blood-brain barrier. Virulence 2012; 3:193-201. [PMID: 22460644 PMCID: PMC3396698 DOI: 10.4161/viru.19013] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Cerebral malaria is the most severe pathology caused by the malaria parasite, Plasmodium falciparum. The pathogenic mechanisms leading to cerebral malaria are still poorly defined as studies have been hampered by limited accessibility to human tissues. Nevertheless, histopathology of post-mortem human tissues and mouse models of cerebral malaria have indicated involvement of the blood-brain barrier in cerebral malaria. In contrast to viruses and bacteria, malaria parasites do not infiltrate and infect the brain parenchyma. Instead, rupture of the blood-brain barrier occurs and may lead to hemorrhages resulting in neurological alterations. Here, we review the most recent findings from human studies and mouse models on the interactions of malaria parasites and the blood-brain barrier, shedding light on the pathogenesis of cerebral malaria, which may provide directions for possible interventions.
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Affiliation(s)
- Laurent Rénia
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A STAR), Biopolis, Singapore.
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Rankin JC, Lorenz E, Neuhann F, Yé M, Sié A, Becher H, Ramroth H. Exploring the role narrative free-text plays in discrepancies between physician coding and the InterVA regarding determination of malaria as cause of death, in a malaria holo-endemic region. Malar J 2012; 11:51. [PMID: 22353802 PMCID: PMC3359180 DOI: 10.1186/1475-2875-11-51] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 02/21/2012] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND In countries where tracking mortality and clinical cause of death are not routinely undertaken, gathering verbal autopsies (VA) is the principal method of estimating cause of death. The most common method for determining probable cause of death from the VA interview is Physician-Certified Verbal Autopsy (PCVA). A recent alternative method to interpret Verbal Autopsy (InterVA) is a computer model using a Bayesian approach to derive posterior probabilities for causes of death, given an a priori distribution at population level and a set of interview-based indicators. The model uses the same input information as PCVA, with the exception of narrative text information, which physicians can consult but which were not inputted into the model. Comparing the results of physician coding with the model, large differences could be due to difficulties in diagnosing malaria, especially in holo-endemic regions. Thus, the aim of the study was to explore whether physicians' access to electronically unavailable narrative text helps to explain the large discrepancy in malaria cause-specific mortality fractions (CSMFs) in physician coding versus the model. METHODS Free-texts of electronically available records (N = 5,649) were summarised and incorporated into the InterVA version 3 (InterVA-3) for three sub-groups: (i) a 10%-representative subsample (N = 493) (ii) records diagnosed as malaria by physicians and not by the model (N = 1035), and (iii) records diagnosed by the model as malaria, but not by physicians (N = 332). CSMF results before and after free-text incorporation were compared. RESULTS There were changes of between 5.5-10.2% between models before and after free-text incorporation. No impact on malaria CSMFs was seen in the representative sub-sample, but the proportion of malaria as cause of death increased in the physician sub-sample (2.7%) and saw a large decrease in the InterVA subsample (9.9%). Information on 13/106 indicators appeared at least once in the free-texts that had not been matched to any item in the structured, electronically available portion of the Nouna questionnaire. DISCUSSION Free-texts are helpful in gathering information not adequately captured in VA questionnaires, though access to free-text does not explain differences in physician and model determination of malaria as cause of death.
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Affiliation(s)
- Johanna C Rankin
- Institute of Public Health, University Hospital of Heidelberg, Heidelberg, Germany
| | - Eva Lorenz
- Institute of Public Health, University Hospital of Heidelberg, Heidelberg, Germany
| | - Florian Neuhann
- Institute of Public Health, University Hospital of Heidelberg, Heidelberg, Germany
| | - Maurice Yé
- Centre de Recherche en Santé de Nouna, Nouna, Burkina Faso
| | - Ali Sié
- Centre de Recherche en Santé de Nouna, Nouna, Burkina Faso
| | - Heiko Becher
- Institute of Public Health, University Hospital of Heidelberg, Heidelberg, Germany
| | - Heribert Ramroth
- Institute of Public Health, University Hospital of Heidelberg, Heidelberg, Germany
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Erythropoietin levels are not independently associated with malaria-attributable severe disease in Mozambican children. PLoS One 2011; 6:e24090. [PMID: 21912616 PMCID: PMC3166067 DOI: 10.1371/journal.pone.0024090] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Accepted: 07/29/2011] [Indexed: 12/26/2022] Open
Abstract
Background Severe malaria is difficult to differentiate from other forms of malaria or other infections with similar symptoms. Any parameter associated to malaria-attributable severe disease could help to improve severe malaria diagnosis. Methodology This study assessed the relation between erythropoietin (EPO) and malaria-attributable severe disease in an area of Mozambique with moderate malaria transmission. 211 children <5 years, recruited at Manhiça District Hospital or in the surrounding villages, were included in one of the following groups: severe malaria (SM, n = 44), hospital malaria without severity (HM, n = 49), uncomplicated malaria (UM, n = 47), invasive bacterial infection without malaria parasites (IBI, n = 39) and healthy community controls (C, n = 32). Malaria was diagnosed by microscopy and IBI by blood/cerebrospinal fluid culture. Principal Findings Mean EPO concentration in the control group was 20.95 U/l (SD = 2.96 U/l). Values in this group were lower when compared to each of the clinical groups (p = 0.026 C versus UM, p<0.001 C vs HM, p<0.001 C vs SM and p<0.001 C vs IBI). In the 3 malaria groups, values increased with severity [mean = 40.82 U/l (SD = 4.07 U/l), 125.91 U/l (SD = 4.99U/l) and 320.87 U/l (SD = 5.91U/l) for UM, HM and SM, respectively, p<0.001]. The IBI group [mean = 101.75 U/l (SD = 4.12 U/l)] presented lower values than the SM one (p = 0.002). In spite of the differences, values overlapped between study groups and EPO levels were only associated to hemoglobin. Hemoglobin means of the clinical groups were 93.98 g/dl (SD = 14.77 g/dl) for UM, 75.96 g/dl (SD = 16.48 g/dl) for HM, 64.34 g/dl (SD = 22.99 g/dl) for SM and 75.67 g/dl (SD = 16.58 g/dl) for IBI. Conclusions Although EPO levels increase according to malaria severity and are higher in severe malaria than in bacteremia, the utility of EPO to distinguish malaria-attributable severe disease is limited due to the overlap of values between the study groups and the main role of hemoglobin in the expression of EPO.
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Ouma C, Davenport GC, Garcia S, Kempaiah P, Chaudhary A, Were T, Anyona SB, Raballah E, Konah SN, Hittner JB, Vulule JM, Ong'echa JM, Perkins DJ. Functional haplotypes of Fc gamma (Fcγ) receptor (FcγRIIA and FcγRIIIB) predict risk to repeated episodes of severe malarial anemia and mortality in Kenyan children. Hum Genet 2011; 131:289-99. [PMID: 21818580 DOI: 10.1007/s00439-011-1076-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Accepted: 07/19/2011] [Indexed: 12/29/2022]
Abstract
Development of protective immunity against Plasmodium falciparum is partially mediated through binding of malaria-specific IgG to Fc gamma (γ) receptors. Variations in human FcγRIIA-H/R-131 and FcγRIIIB-NA1/NA2 affect differential binding of IgG sub-classes. Since variability in FcγR may play an important role in severe malarial anemia (SMA) pathogenesis by mediating phagocytosis of red blood cells and triggering cytokine production, the relationship between FcγRIIA-H/R131 and FcγRIIIB-NA1/NA2 haplotypes and susceptibility to SMA (Hb < 6.0 g/dL) was investigated in Kenyan children (n = 528) with acute malaria residing in a holoendemic P. falciparum transmission region. In addition, the association between carriage of the haplotypes and repeated episodes of SMA and all-cause mortality were investigated over a 3-year follow-up period. Since variability in FcγR can alter interferon (IFN)-γ production, a mediator of innate and adaptive immune responses, functional associations between the haplotypes and IFN-γ were also explored. During acute malaria, children with SMA had elevated peripheral IFN-γ levels (P = 0.006). Although multivariate logistic regression analyses (controlling for covariates) revealed no associations between the FcγR haplotypes and susceptibility to SMA during acute infection, the FcγRIIA-131H/FcγRIIIB-NA1 haplotype was associated with decreased peripheral IFN-γ (P = 0.046). Longitudinal analyses showed that carriage of the FcγRIIA-131H/FcγRIIIB-NA1 haplotype was associated with reduced risk of SMA (RR 0.65, 95% CI 0.46-0.90; P = 0.012) and all-cause mortality (P = 0.002). In contrast, carriers of the FcγRIIA-131H/FcγRIIIB-NA2 haplotype had increased susceptibility to SMA (RR 1.47, 95% CI 1.06-2.04; P = 0.020). Results here demonstrate that variation in the FcγR gene alters susceptibility to repeated episodes of SMA and mortality, as well as functional changes in IFN-γ production.
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Affiliation(s)
- Collins Ouma
- Centre for Global Health Research, Kenya Medical Research Institute, University of New Mexico/KEMRI Laboratories of Parasitic and Viral Diseases, Kisumu, Kenya
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Vekemans J, Marsh K, Greenwood B, Leach A, Kabore W, Soulanoudjingar S, Asante KP, Ansong D, Evans J, Sacarlal J, Bejon P, Kamthunzi P, Salim N, Njuguna P, Hamel MJ, Otieno W, Gesase S, Schellenberg D. Assessment of severe malaria in a multicenter, phase III, RTS, S/AS01 malaria candidate vaccine trial: case definition, standardization of data collection and patient care. Malar J 2011; 10:221. [PMID: 21816031 PMCID: PMC3221632 DOI: 10.1186/1475-2875-10-221] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Accepted: 08/04/2011] [Indexed: 11/10/2022] Open
Abstract
Background An effective malaria vaccine, deployed in conjunction with other malaria interventions, is likely to substantially reduce the malaria burden. Efficacy against severe malaria will be a key driver for decisions on implementation. An initial study of an RTS, S vaccine candidate showed promising efficacy against severe malaria in children in Mozambique. Further evidence of its protective efficacy will be gained in a pivotal, multi-centre, phase III study. This paper describes the case definitions of severe malaria used in this study and the programme for standardized assessment of severe malaria according to the case definition. Methods Case definitions of severe malaria were developed from a literature review and a consensus meeting of expert consultants and the RTS, S Clinical Trial Partnership Committee, in collaboration with the World Health Organization and the Malaria Clinical Trials Alliance. The same groups, with input from an Independent Data Monitoring Committee, developed and implemented a programme for standardized data collection. The case definitions developed reflect the typical presentations of severe malaria in African hospitals. Markers of disease severity were chosen on the basis of their association with poor outcome, occurrence in a significant proportion of cases and on an ability to standardize their measurement across research centres. For the primary case definition, one or more clinical and/or laboratory markers of disease severity have to be present, four major co-morbidities (pneumonia, meningitis, bacteraemia or gastroenteritis with severe dehydration) are excluded, and a Plasmodium falciparum parasite density threshold is introduced, in order to maximize the specificity of the case definition. Secondary case definitions allow inclusion of co-morbidities and/or allow for the presence of parasitaemia at any density. The programmatic implementation of standardized case assessment included a clinical algorithm for evaluating seriously sick children, improvements to care delivery and a robust training and evaluation programme for clinicians. Conclusions The case definition developed for the pivotal phase III RTS, S vaccine study is consistent with WHO recommendations, is locally applicable and appropriately balances sensitivity and specificity in the diagnosis of severe malaria. Processes set up to standardize severe malaria data collection will allow robust assessment of the efficacy of the RTS, S vaccine against severe malaria, strengthen local capacity and benefit patient care for subjects in the trial. Trial registration Clinicaltrials.gov NCT00866619
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Graz B, Willcox M, Szeless T, Rougemont A. "Test and treat" or presumptive treatment for malaria in high transmission situations? A reflection on the latest WHO guidelines. Malar J 2011; 10:136. [PMID: 21599880 PMCID: PMC3123602 DOI: 10.1186/1475-2875-10-136] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Accepted: 05/20/2011] [Indexed: 11/25/2022] Open
Abstract
Recent WHO guidelines recommend a universal "test and treat" strategy for malaria, mainly by use of rapid diagnostic test (RDT) in all areas. The evidence for this approach is questioned here as there is a risk of over-reliance on parasitological diagnosis in high transmission situations, which still exist. In such areas, when a patient has fever or other malaria symptoms, the presence of Plasmodium spp neither reliably confirms malaria as the cause of the fever, nor excludes the possibility of other diseases. This is because the patient may be an asymptomatic carrier of malaria parasites and suffer from another disease. To allow clinicians to perform their work adequately, local epidemiologic data are necessary. One size does not fit all. If parasite prevalence in the population is low, a diagnostic test is relevant; if the prevalence is high, the test does not provide information of any clinical usefulness, as happens with any test in medicine when the prevalence of the tested characteristic is high in the healthy population. It should also be remembered that, if in some cases anti-malarials are prescribed to parasite-negative patients, this will not increase selection pressure for drug resistance, because the parasite is not there. In high transmission situations at least, other diagnoses should be sought in all patients, irrespective of the presence of malaria parasites. For this, clinical skills (but not necessarily physicians) are irreplaceable, in order to differentiate malaria from other causes of acute fever, such as benign viral infection or potentially dangerous conditions, which can all be present with the parasite co-existing only as a "commensal" or silent undesirable guest.
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Affiliation(s)
- Bertrand Graz
- Institute of Social and Preventive Medicine, University of Geneva, Switzerland.
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Conroy AL, Phiri H, Hawkes M, Glover S, Mallewa M, Seydel KB, Taylor TE, Molyneux ME, Kain KC. Endothelium-based biomarkers are associated with cerebral malaria in Malawian children: a retrospective case-control study. PLoS One 2010; 5:e15291. [PMID: 21209923 PMCID: PMC3012131 DOI: 10.1371/journal.pone.0015291] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Accepted: 11/10/2010] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Differentiating cerebral malaria (CM) from other causes of serious illness in African children is problematic, owing to the non-specific nature of the clinical presentation and the high prevalence of incidental parasitaemia. CM is associated with endothelial activation. In this study we tested the hypothesis that endothelium-derived biomarkers are associated with the pathophysiology of severe malaria and may help identify children with CM. METHODS AND FINDINGS Plasma samples were tested from children recruited with uncomplicated malaria (UM; n = 32), cerebral malaria with retinopathy (CM-R; n = 38), clinically defined CM without retinopathy (CM-N; n = 29), or non-malaria febrile illness with decreased consciousness (CNS; n = 24). Admission levels of angiopoietin-2 (Ang-2), Ang-1, soluble Tie-2 (sTie-2), von Willebrand factor (VWF), its propeptide (VWFpp), vascular endothelial growth factor (VEGF), soluble ICAM-1 (sICAM-1) and interferon-inducible protein 10 (IP-10) were measured by ELISA. Children with CM-R had significantly higher median levels of Ang-2, Ang-2:Ang-1, sTie-2, VWFpp and sICAM-1 compared to children with CM-N. Children with CM-R had significantly lower median levels of Ang-1 and higher median concentrations of Ang-2:Ang-1, sTie-2, VWF, VWFpp, VEGF and sICAM-1 compared to UM, and significantly lower median levels of Ang-1 and higher median levels of Ang-2, Ang-2:Ang-1, VWF and VWFpp compared to children with fever and altered consciousness due to other causes. Ang-1 was the best discriminator between UM and CM-R and between CNS and CM-R (areas under the ROC curve of 0.96 and 0.93, respectively). A comparison of biomarker levels in CM-R between admission and recovery showed uniform increases in Ang-1 levels, suggesting this biomarker may have utility in monitoring clinical response. CONCLUSIONS These results suggest that endothelial proteins are informative biomarkers of malarial disease severity. These results require validation in prospective studies to confirm that this group of biomarkers improves the diagnostic accuracy of CM from similar conditions causing fever and altered consciousness.
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Affiliation(s)
- Andrea L. Conroy
- Sandra A. Rotman Laboratories, McLaughlin-Rotman Centre for Global Health, University Health Network-Toronto General Hospital, University of Toronto, Toronto, Canada
| | - Happy Phiri
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Michael Hawkes
- Sandra A. Rotman Laboratories, McLaughlin-Rotman Centre for Global Health, University Health Network-Toronto General Hospital, University of Toronto, Toronto, Canada
| | - Simon Glover
- College of Medicine, University of Malawi, Blantyre, Malawi
| | - Mac Mallewa
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- School of Tropical Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Karl B. Seydel
- Blantyre Malaria Project, College of Medicine, University of Malawi, Blantyre, Malawi
- Department of Internal Medicine, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, United States of America
| | - Terrie E. Taylor
- Blantyre Malaria Project, College of Medicine, University of Malawi, Blantyre, Malawi
- Department of Internal Medicine, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, United States of America
| | - Malcolm E. Molyneux
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- College of Medicine, University of Malawi, Blantyre, Malawi
- School of Tropical Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Kevin C. Kain
- Sandra A. Rotman Laboratories, McLaughlin-Rotman Centre for Global Health, University Health Network-Toronto General Hospital, University of Toronto, Toronto, Canada
- Tropical Disease Unit, Division of Infectious Diseases, Department of Medicine, University of Toronto, Toronto, Canada
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Mwaniki MK, Talbert AW, Mturi FN, Berkley JA, Kager P, Marsh K, Newton CR. Congenital and neonatal malaria in a rural Kenyan district hospital: an eight-year analysis. Malar J 2010; 9:313. [PMID: 21054891 PMCID: PMC2988044 DOI: 10.1186/1475-2875-9-313] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Accepted: 11/06/2010] [Indexed: 11/17/2022] Open
Abstract
Background Malaria remains a significant burden in sub-Saharan Africa. However, data on burden of congenital and neonatal malaria is scarce and contradictory, with some recent studies reporting a high burden. Using prospectively collected data on neonatal admissions to a rural district hospital in a region of stable malaria endemicity in Kenya, the prevalence of congenital and neonatal malaria was described. Methods From 1st January 2002 to 31st December 2009, admission and discharge information on all neonates admitted to Kilifi District Hospital was collected. At admission, blood was also drawn for routine investigations, which included a full blood count, blood culture and blood slide for malaria parasites. Results Of the 5,114 neonates admitted during the eight-year surveillance period, blood slide for malaria parasites was performed in 4,790 (93.7%). 18 (0.35%) neonates with Plasmodium falciparum malaria parasitaemia, of whom 11 were admitted within the first week of life and thus classified as congenital parasitaemia, were identified. 7/18 (39%) had fever. Parasite densities were low, ≤50 per μl in 14 cases. The presence of parasitaemia was associated with low haemoglobin (Hb) of <10 g/dl (χ2 10.9 P = 0.001). The case fatality rate of those with and without parasitaemia was similar. Plasmodium falciparum parasitaemia was identified as the cause of symptoms in four neonates. Conclusion Congenital and neonatal malaria are rare in this malaria endemic region. Performing a blood slide for malaria parasites among sick neonates in malaria endemic regions is advisable. This study does not support routine treatment with anti-malarial drugs among admitted neonates with or without fever even in a malaria endemic region.
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Affiliation(s)
- Michael K Mwaniki
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Box 230, Kilifi, Kenya.
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