RESUMEN
To assess the effects of iron therapy on platelet monoamine oxidase (MAO) activity and urinary excretion of total metanephrines (MN) in infants and young children with iron deficiency anemia, 24 subjects were tested before and after one month of oral iron treatment. Thirteen healthy children comprised the control group. In the control group, platelet MAO level was 0.21 +/- 0.02 U/mg protein (mean +/- SE), urinary total metanephrine was 2.51 +/- 0.47 micrograms/mg creatinine. In cases with iron deficiency, mean platelet MAO level was 47.6% lower (p less than 0.005) whereas mean urinary metanephrine plus normetanephrine (MN-NMN) was only 20.7% lower (p greater than 0.05) than the control values. After one month, the anemic patients receiving oral iron therapy showed a significant increase in hemoglobin concentration, per cent transferrin saturation and platelet MAO activity (p less than 0.05). However, urinary metanephrine excretion was found to be lower in this group when compared to the metanephrine levels in iron deficiency before the medication (p less than 0.05). Although hemoglobin and transferrin saturation did not return to normal levels, these findings suggested that platelet MAO activity increased and urinary excretion of metanephrines decreased after iron medication.