The burden and consequences of inherited blood disorders among young children in western K enya

Although inherited blood disorders are common among children in many parts of A frica, 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 K enya. Haemoglobin ( H b), 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 ( G 6 PD ) 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 ( H b SS ) 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 G 6 PD deficiency. There were no significant differences in the distribution of malaria by the measured blood disorders, except among males with G 6 PD deficiency who had a lower prevalence of clinical malaria than males of normal G 6 PD 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 K enya and are important contributors to anaemia.