Performance of iron deficiency indicators in a malaria-holoendemic population

To determine if malarial infection influenced indicators of iron deficiency, we examined relationships among hemoglobin (Hb), erythrocyte protoporphyrin (EP), serum ferritin (SF) and malaria parasitemia in 3189 school children in Zanzibar, Tanzania. 62% of the children had circulating P. falciparum parasites. Iron deficiency was prevalent: 63% of Hb values were <110 g/L, 59% of EP values were >80 umol/mol heme, and 41 % of SF values were <12 ug/L. Neither Hb nor EP values were related to malaria parasitemia. SF was not affected by parasitemia below 1000 parasites/uL, and SF increased only 1.5 ug/L for each gain of 1000 parasites/uL above that threshold. The direct relationship of SF to Hb and inverse relationship of SF to EP were strong and did not differ by level of malarial infection. A strong inverse relationship of EP with Hb was attenuated slightly when parasitemia exceeded 1000 parasites/uL, perhaps attributable to the dyserythropoeisis of malaria. Because only 13.8% of the population had parasitemias > 1000 parasites/uL, and because the effect of parasitemia on iron status indicators was minor, population prevalences of iron deficiency were not biased by malaria. We conclude that Hb, EP, and SF perform reliably in a malaria-holoendemic population of older children. in whom malarial infection is infrequently associated with disease.