Should we limit the ferritin upper threshold to 500 ng/ml in CKD patients?Nephrol News Issues. 2007 Jan; 21(1):34-8.NN
The new National Kidney Foundation's Kidney Disease Outcome Quality Initiative clinical practice guidelines for anemia management in chronic kidney disease include several important modifications to the previous recommendations. These changes may have major implications in clinical practice and outcome of the chronic kidney disease patient population. Among the important guideline modifications are the elimination of the upper thresholds for hemoglobin (12 g/dL), transferrin saturation ratio (TSAT, v 50%) and ferritin (800 ng/ml). There are, however, additional recommendations pertaining to anemia management when hemoglobin is above 13 g/dL or serum ferritin above 500 ng/ml. The KDOQI anemia working group explains that the upper ferritin level of 500 ng/ml is not a stopping point for IV iron administration, but adds that decisions regarding IV iron administration should weigh erythropoietin responsiveness, hemoglobin and transferrin saturation level, and the patient's clinical status.The selected upper ferritin level of 500 ng/ml lacks adequate scientific evidence in the CKD population. Approximately half of all maintenance hemodialysis patients in the United States may have a serum ferritin above 500 ng/ml. Serum ferritin in 500-1,200 ng/ml range is not associated with increased death risk in hemodialysis patients if controlled for the confounding effect of malnutrition and inflammation. Given the lack of support from the literature, any attempt to contemplate an upper limit for serum ferritin would be arbitrary, and would not serve to improve the quality of treatment in the CKD population.