DEPLETION OF VITAMIN C IN PATIENTS WITH THALASSEMIA MAJOR. EFFECT OF VITAMIN C REPLETION ON DESFERRIOXAMINE INDUCED URINARY IRON EXCRETION

Abstract

Patients with iron overload have vit. C deficiency in tissue stores as measured by vit. C content in the white blood cells. It has also been shown that repletion of vit. C. tissue stores increases the efficacy of iron chelation in urine by Desferrioxamine (DF). Sixteen patients with thalassemia major all on a hypertransfusion program and some on chelation therapy as well were studied for vit. C content. Fourteen of the 16 had depletion of vit. C content (4.5-21.5 mcg × 108 WBC; normal range: 30.0-44.2 meg × 108 WBC). Urine was collected for 24 hours after giving 500 mgm of DF, I.M. Iron excretion in urine varied from 0.2-2.3 mgm% of urine (mean 0.95). Patients were given vit. C 500 mgm d. to 500 mgm t.i.d., orally. At 6 weeks, urinary iron excretion, after 500 mgm of DF, I.M., was restudied. There was definite increase in iron excretion in all but one patient (mean 1.5 mgm% of urine). The mean increase for 12 children was 0.56 mgm% of urine. This difference was significant (P<.001). The amount of iron excreted was greater in older patients (i.e. those more overloaded with iron). It would be important to know the simultaneous excretion of iron in the stools and urine after vit. C repletion, as there may be significant change in excretion of iron both in stools and urine. Patients with thalassemia should receive vit. C as the majority are deficient in this vitamin.