A simultaneous study of glycine-N 15 incorporation into uric acid and heme, and of Fe 59 utilization, in a case of gout associated with polycythemia secondary to congenital heart disease

Abstract

By simultaneous use of glycine-N 15 and Fe 59 as tracers the interrelationships between purine, porphyrin and iron metabolism were studied in a patient with gout associated with polycythemia secondary to congenital heart disease. The time course of glycine-N 15 incorporation into uric acid was unlike that previously observed in normal subjects and in patients with primary gout, in whom peak enrichment of uric acid N 15 occurs within two to four days of administration of the isotope. In the case recorded herein there was progressive increase in the N 15 abundance of the urinary uric acid until the tenth day. The protracted uric acid biosynthesis observed in this instance of secondary gout is presumed to reflect the augmented turnover of red cell precursor nucleic acids associated with increased erythropoiesis characterizing the polycythemic state. The time course of glycine-N 15 incorporation into heme in this case of secondary polycythemia did not deviate significantly from the normal, thus corresponding with the similar findings reported in polycythemia vera. As in other recorded instances of increased crythropoietic activity due to primary and secondary polycythemia, the initial half-time of disappearance of injected Fe 59 from the blood plasma was reduced (in this case to thirty-one minutes), the rate of Fe 59 incorporation into circulating red cells was correspondingly accelerated and the utilization of the Fe 59 for erythrogenesis was increased, by the seventh day, to over 90 per cent of the amount injected. The turnover rate of Fe 59 was accelerated both in the plasma and in the red cells.