| [ Summary ] |
A small number, probably 15 to 20％, of patients may be defined as a poor responders or resistant to erythropoiesis -stimulating agent (ESA) treatment. The most frequent cause of resistance is known to be "relative" iron deficiency, due to a state of increased iron demand during treatment. However, HD-related problems, such as poor conditioning of dialysis fluids, low biocompatibility of dialysis membranes, and dialysis dosage, may also affect ESA responsiveness. Contaminated dialysates may enhance inflammatory cytokine production, inhibiting marrow erythropoiesis either directly or by limiting iron utilization. Low dialysis dosage is also a cause of poor responsiveness to ESAs, through the inhibitory effects of accumulating uremic toxins or decreasing red blood cell life span. Thus, many factors related to dialysis should be considered in poor ESA responder cases. |