Iron status and iron supplementation in peritoneal dialysis patients

Iron deficiency represents an important problem in peritoneal dialysis pati ents, especially during erythropoietin therapy. A combination of serum ferr itin, transferrin saturation, and/or the percentage of hypochromic red cell s should be used to assess iron status in peritoneal dialysis patients. Pri marily, oral iron supplementation should be the preferred therapy. However, most of the studies using oral substitution in erythropoietin-treated peri toneal dialysis patients show a progressive decline of serum ferritin. Ther efore, parenteral iron supplementation is required in part of the patients, and the intravenous route should be preferred in these cases. Intravenous iron therapy is recommended if serum ferritin falls below 100 mu g/liter an d should be stopped if the serum ferritin level is more than 650 mu g/liter . The optimal form of intravenous iron supplementation is still unclear. In jections once to three times per week restrict the patients' flexibility, b ut application of higher doses in longer intervals may lead to an impairmen t of neutrophil functions, probably connected to a higher risk of infection . We treated 17 stable peritoneal dialysis patients with 100 or 200 mg iron saccharate monthly over a period of six months and found an increase of tr ansferrin saturation (from 12.1 +/- 1.6 to 20.9 +/- 2.3%, P = 0.026), serum ferritin (from 100.4 +/- 32.0 to 372.4 +/- 54.6 mu g/liter, NS) and hemato crit (from 32.0 +/- 0.8% to 35.1 +/- 0.9%, P = 0.099). The required erythro poietin dosage could be reduced significantly (from 148.4 +/- 30.3 to 69.4 +/- 19.5 U/kg/week, P = 0.025). Side effects occurred in 0.9% after applica tion of 100 mg and in 5.9% after injection of 200 mg iron saccharate. The i ncidence of catheter infections and peritonitis was the same in the period before and after the start of treatment. Further studies are needed to find the most suitable regime of iron supplementation for peritoneal dialysis p atients.