Management of anemia by convective treatments

Anemia secondary to chronic kidney disease is a complex syndrome. Adequate dialysis can contribute to its correction by removing small and possibly medium/large molecules that may inhibit erythropoiesis. A clear relationship among hemoglobin, erythropoiesis stimulating agent (ESA) dose and increase in dialysis dose has been pointed out by a number of prospective and retrospective studies. Increasing attention has also been paid to the relationship between dialysis, increased inflammatory stimulus and ESA response, as dialysate contamination and low compatible treatments may increase cytokine production and consequently inhibit erythropoiesis. As medium/large molecular weight inhibitors can be removed only by more permeable membranes, convective treatment sand, particularly, online treatments, could theoretically improve anemia correction by two mechanisms: higher removal of medium and large solutes (possibly containing bone marrow inhibitors) and reduced microbiological and pyrogenic contamination of the dialysate. Unfortunately, available results are conflicting. Large, prospective, randomized studies on this topic are still needed.