title: Endothelium-based biomarkers are associated with cerebral malaria in Malawian children: a retrospective case-control study.
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.
  
  
  RESULTS
  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.
authors.affiliation: Sandra A. Rotman Laboratories, McLaughlin-Rotman Centre for Global Health, University Health Network-Toronto General Hospital, University of Toronto, Toronto, Canada.
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Conroy
authors.forename: Happy
authors.initials: H
authors.lastname: Phiri
authors.forename: Michael
authors.initials: M
authors.lastname: Hawkes
authors.forename: Simon
authors.initials: S
authors.lastname: Glover
authors.forename: Mac
authors.initials: M
authors.lastname: Mallewa
authors.forename: Karl B
authors.initials: KB
authors.lastname: Seydel
authors.forename: Terrie E
authors.initials: TE
authors.lastname: Taylor
authors.forename: Malcolm E
authors.initials: ME
authors.lastname: Molyneux
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Kain
mesh_terms: D015415:Biomarkers / Q000378:metabolism*; D001921:Brain / Q000469:parasitology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004730:Endothelium, Vascular / Q000378:metabolism*; D005260:Female; D006801:Humans; D007223:Infant; D016779:Malaria, Cerebral / Q000378:metabolism*; D008295:Malawi; D008297:Male; D009885:Ophthalmology / Q000379:methods; D011446:Prospective Studies; D012189:Retrospective Studies
chemical_list: D015415:Biomarkers