Iron and infection: the clinical evidence.

Iron deficiency is prevalent in childhood in the developed and developing countries. Programs of presumptive therapy, mass supplementation and food fortification have been introduced in many countries. The unresolved debate over the interaction of iron and infection in the clinical setting prompts re-evaluation of these practices. Situations of iron overload are associated with increased susceptibility to certain infections, although the exact mechanisms may vary with the main pathology. Iron treatment has been associated with acute exacerbations of infection, in particular malaria. In most instances parenteral iron was used. In the neonate parenteral iron is associated with serious E. coli sepsis. In one country, with endemic malaria, parenteral iron was associated with increased rates of malaria and increased morbidity due to respiratory disease in infants. In contrast in non-malarious countries studies of oral iron supplementation have if anything shown a reduction in infectious morbidity. Methodological problems in the latter reports indicate the need for further controlled prospective studies with accurate morbidity recording if informed recommendations are to be made.