[Anemia in Chronic Kidney Disease: from facts to clinical practice]

Anemia in Chronic Kidney Disease (CKD) is present in approximately 90% of patients with glomerular filtration rate below 25-30 mL/min. It's impact in the quality of life makes it one of the major problems in CKD patients. Although the etiology is multifactorial the suboptimal production of erithropoietin caused by renal mass loss appears to be of major importance. After the introduction of Erythropoiesis Stimulating Agents (ESA's) the treatment of anemia in CKD has changed dramatically. Today, ESA's have a fundamental role in the increase of Hb values in CKD. Previously, severe anemia was frequent and blood transfusions were often necessary to improve patients quality of life. Small observational studies performed during the late 80's suggested that high Hb values may be benefic in CKD patients. At that time, the use of ESA's became universal. Later randomized trials tried to show the positive impact of rising Hb levels with ESA's in patient's outcome. The results of such studies were disappointing. Some of them even documented higher mortality associated with near normal Hb levels, failing to prove the real benefit of the complete correction of CKD anemia. We're still waiting for new randomized trials to be elucidated about the optimal target of Hb to achieve in CKD and the treatment algorithm with ESA's. Current evidence suggests that Hb values must be targetted at 11-12 g/dL, without reaching the complete correction of anaemia.