title: The burden and consequences of inherited blood disorders among young children in western Kenya.
abstract: Although inherited blood disorders are common among children in many parts of Africa, limited data are available about their prevalence or contribution to childhood anaemia. We conducted a cross-sectional survey of 858 children aged 6-35 months who were randomly selected from 60 villages in western Kenya. Haemoglobin (Hb), ferritin, malaria, C-reactive protein (CRP) and retinol binding protein (RBP) were measured from capillary blood. Using polymerase chain reaction (PCR), Hb type, -3.7 kb alpha-globin chain deletion, glucose-6-phosphate dehydrogenase (G6PD) genotype and haptoglobin (Hp) genotype were determined. More than 2 out of 3 children had at least one measured blood disorder. Sickle cell trait (HbAS) and disease (HbSS) were found in 17.1% and 1.6% of children, respectively; 38.5% were heterozygotes and 9.6% were homozygotes for α(+) -thalassaemia. The Hp 2-2 genotype was found in 20.4% of children, whereas 8.2% of males and 6.8% of children overall had G6PD deficiency. There were no significant differences in the distribution of malaria by the measured blood disorders, except among males with G6PD deficiency who had a lower prevalence of clinical malaria than males of normal G6PD genotype (P = 0.005). After excluding children with malaria parasitaemia, inflammation (CRP > 5 mg L(-1) ), iron deficiency (ferritin < 12 μg L(-1) ) or vitamin A deficiency (RBP < 0.7 μg L(-1) ), the prevalence of anaemia among those without α(+) -thalassaemia (43.0%) remained significantly lower than that among children who were either heterozygotes (53.5%) or homozygotes (67.7%, P = 0.03). Inherited blood disorders are common among pre-school children in western Kenya and are important contributors to anaemia.
authors.affiliation: Nutrition Branch, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA; Department of Pediatrics and Global Health, Emory University, Atlanta, Georgia, USA.
authors.forename: Parminder S
authors.initials: PS
authors.lastname: Suchdev
authors.forename: Laird J
authors.initials: LJ
authors.lastname: Ruth
authors.forename: Marie
authors.initials: M
authors.lastname: Earley
authors.forename: Alex
authors.initials: A
authors.lastname: Macharia
authors.forename: Thomas N
authors.initials: TN
authors.lastname: Williams
mesh_terms: D000755:Anemia, Sickle Cell / Q000453:epidemiology* / Q000235:genetics; D002097:C-Reactive Protein / Q000378:metabolism; D002675:Child, Preschool; D017281:Cost of Illness; D003430:Cross-Sectional Studies; D005260:Female; D005293:Ferritins / Q000097:blood; D017353:Gene Deletion; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics; D005955:Glucosephosphate Dehydrogenase Deficiency / Q000453:epidemiology* / Q000235:genetics; D006242:Haptoglobins; D006454:Hemoglobins / Q000378:metabolism; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007223:Infant; D007630:Kenya / Q000453:epidemiology; D008288:Malaria / Q000453:epidemiology* / Q000235:genetics; D008297:Male; D015995:Prevalence; D012177:Retinol-Binding Proteins / Q000378:metabolism; D012805:Sickle Cell Trait / Q000453:epidemiology / Q000235:genetics; D013789:Thalassemia / Q000453:epidemiology* / Q000235:genetics
chemical_list: D006242:Haptoglobins; D006454:Hemoglobins; D012177:Retinol-Binding Proteins; D002097:C-Reactive Protein; D005293:Ferritins; D005954:Glucosephosphate Dehydrogenase