Serial ferritin concentrations in hemodialysis patients receiving intravenous iron

Treatment of the anemia of chronic renal failure with intravenous iron and erythropoietin is highly effective, but frequently leads to ferritin levels which are much higher than those seen in the general population. High ferritin concentrations raise concern about the potential toxicity of increased body iron stores.

We retrospectively evaluated parameters of iron metabolism over a 4-year period among all our chronic hemodialysis patients who had been receiving intravenous iron and erythropoietin. Initially, patients received intermittent infusions of 300 mg intravenous iron x 3 doses for a low ferritin or low percent saturation of total iron binding capacity (TIBC), but this protocol was subsequently changed to weekly or biweekly infusions of 50-100 mg.

We observed an improvement in average hemoglobin values, modest increases in serum iron and saturation of iron binding capacity, and a 125% increase in ferritin levels over 4 years. TIBC decreased. Overall, ferritin values increased 79 microg/l for each 1% increase in TIBC saturation. Ten patients with ferritin concentration greater than 1,000 pg/l received a three month course of vitamin C with no decline in the ferritin concentration.

Current protocols for iron delivery may result in progressive increases in ferritin levels. Concern about the risks of iron overload should temper the quantity of iron used in dialysis programs.