Functional iron deficiency in hemodialysis patients with high ferritin

Abstract

Although functional iron deficiency (FID) may be present in hemodialysis (HD) patients with high serum ferritin levels (>800 ng/mL), current protocols often preclude the use of intravenous (IV) iron in these patients. However, it has not been demonstrated that iron supplementation during erythropoietin therapy is ineffective or unsafe in increasing hemoglobin (Hb) levels in patients with high serum ferritin. This report describes the hematologic efficacy and safety of ferric gluconate (FG) therapy in patients with serum ferritin >800 ng/mL. A retrospective analysis was performed on HD patients at a single California dialysis center from January 1 to December 31, 2003. Patients classified as having high ferritin levels (serum ferritin >800 ng/mL on at least 66% of routine monthly measurements and transferrin saturation [TSAT] <25% on at least 1 occasion) were stratified as follows: patients in Group I were suspected of having FID and received FG > or =250 mg IV over a 3-month period when Hb was <11 g/dL, and patients in Group II were thought not to have FID and received <250 mg FG over a 3-month period. Both groups received standard recombinant human erythropoietin therapy as per the unit's protocol. Of 496 patients, 95 exhibited high ferritin and of these, 39 patients had sufficient data for analysis. Group I patients (n=14) showed a significant increase in Hb levels compared with Group II (n=25). There was no increase in ferritin levels in response to iron administration. No significant differences in hospitalizations or infections were observed between groups. Hemodialysis patients with high ferritin levels may have FID, and IV iron therapy safely improves FID in some patients. A larger randomized trial examining the optimal management of iron administration in HD patients with high ferritin levels is warranted.