title: Reduced plasma concentrations of vitamin B6 and increased plasma concentrations of the neurotoxin 3-hydroxykynurenine are associated with nodding syndrome: a case control study in Gulu and Amuru districts, Northern Uganda.
abstract: BACKGROUND
  Nodding syndrome was first reported in Uganda in 2003 among internally displaced populations. Risk factors for the syndrome remain unknown. We therefore explored vitamin B6 deficiency and resulting high 3-hydroxykynurenine (3-HK) levels as risk factor for nodding syndrome in Northern Uganda.
  
  
  METHODS
  Case-control study conducted in Gulu and Amuru districts. Cases were children/young adults with nodding syndrome. Healthy children/young adults were recruited as controls from same community as cases. Data on socio-demographic and other risk factors was collected using questionnaires. Whole blood was collected in EDTA tubes for assay of 3-HK and vitamin B6 using sandwich ELISA. Conditional logistic regression model was used to assess associations.
  
  
  RESULTS
  66 cases and 73 controls were studied. Factors associated with nodding syndrome were being positive for 3-HK (AOR=4.50, p=0.013), vitamin B6 concentration below mean (AOR=7.22, P=0.001), child being taken care of by mother only (AOR=5.43, p=0.011), child being taken care of by guardian (AOR=5.90, p=0.019) and child consuming relief food at weaning (AOR=4.05, p=0.021).
  
  
  CONCLUSIONS
  Having low vitamin B6 concentration which leads to a build up of 3-hydroxykynurenine concentration in cases as a main risk factor. Therefore, cases should be treated with vitamin B6 and community members should be sensitise to ensure adequate dietary intake of vitamin B6 so that the risk of nodding syndrome among children is averted. We encourage future prospective intervention study to be conducted to assess the effect of low vitamin B6 on the development of nodding syndrome via raised 3-HK concentration.
authors.affiliation: Department of Public Health, Faculty of Medicine, Gulu University, P.O Box 166, Gulu.
authors.forename: James Henry
authors.initials: JH
authors.lastname: Obol
authors.affiliation: Department of Medical Biochemistry, Faculty of Medicine, Gulu University, P.O Box 166, Gulu.
authors.forename: Denis Anywar
authors.initials: DA
authors.lastname: Arony
authors.affiliation: Department of Medical Biochemistry, Faculty of Medicine, Gulu University, P.O Box 166, Gulu.
authors.forename: Ronald
authors.initials: R
authors.lastname: Wanyama
authors.affiliation: Department of Microbiology and Immunology, Faculty of Medicine, Gulu University, P.O Box 166, Gulu.
authors.forename: Kenneth Luryama
authors.initials: KL
authors.lastname: Moi
authors.affiliation: Department of Paediatrics and Child Health, Faculty of Medicine, Gulu University, P.O Box 166, Gulu.
authors.forename: Bongomin
authors.initials: B
authors.lastname: Bodo
authors.affiliation: District Health Office, Amuru District Local Government, P.O Box 1074 Gulu.
authors.forename: Patrick Olwedo
authors.initials: PO
authors.lastname: Odong
authors.affiliation: Department of Pathology, Makerere University College of Health Sciences, P.O Box 7072 Kampala.
authors.forename: Michael
authors.initials: M
authors.lastname: Odida
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007737:Kynurenine / Q000031:analogs & derivatives* / Q000097:blood; D016015:Logistic Models; D008297:Male; D064128:Nodding Syndrome / Q000097:blood* / Q000209:etiology; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014454:Uganda; D025101:Vitamin B 6 / Q000097:blood*; D026681:Vitamin B 6 Deficiency / Q000150:complications*; D055815:Young Adult
chemical_list: C005045:3-hydroxykynurenine; D007737:Kynurenine; D025101:Vitamin B 6
keywords: 3-hydroxykynurenine; Nodding syndrome; Northern Uganda; case-control study; vitamin B6