660 MILD LEAD POISONING IS STRONGLY ASSOCIATED WITH IRON DEFICIENCY

Abstract

Anemia is often found in children with severe or symptomatic lead poisoning and is attributed to the inhibition of heme synthesis by lead. During a one year period of using Erythrocyte Protoporphyrin (EP) as a screening test in an urban pediatric clinic, 191 children had elevated EP (≥ 35 μg/dl whole blood) and had further evaluation of lead and iron status. 43 children had a confirmed elevation of blood lead (Pb ≥ 30 μg/dl),33 (77%) with EP ≥ 50 fulfilling the diagnosis of undue lead absorption, a relative mild form of lead poisoning. Of the 43 children with evidence of mild lead poisoning, 38 (86%) also had evidence of iron deficiency based on ferritin ≤ 15 ng/ml and/or transferrin saturation < 16%; 13 (30%) were anemic. This is significantly higher than the rate of iron deficiency of 9% and rate of anemia of 4% in the same general population. This strong association of mild lead poisoning with iron deficiency is in accord with the observation of increased lead absorption in iron deficiency. It is likely that iron deficiency strongly predisposes to lead poisoning and explains, at least in part, the high prevalence of anemia associated with lead poisoning.