Myth: Intravenous iron may be hazardous in infected hemodialysis patients

Abstract

Iron stores become depleted in ESRD patients on hemodialysis due to a variety of reasons including hemolysis during dialysis and blood loss into the dialyzer and tubing. Iron deficiency is assessed by measuring serum ferritin, serum iron, and/or transferrin TSAT (transferrin saturation = total iron/TIBC × 100). Free iron is not detectable in vivo as long as transferrin is less than fully saturated. Serum ferritin is a labile marker affected by chronic infection and inflammation. Also, generally speaking, serum ferritin is a more useful gauge of iron status at lower values than at higher ones. A high serum ferritin level is associated with altered chemotactic and phagocytic properties of neutrophils, thereby reducing their ability to kill invading pathogens. However, unanswered is the question of whether serum ferritin levels are elevated due to increased iron stores or infection. Infection, per se, may elevate serum ferritin levels inducing neutrophil dysfuntion. When studies control for covariates, such as use of catheters and previous infections, the purported infectious risk associated with iron administration or elevated serum ferritin levels is reduced or eliminated.