Response of hematologic parameters to darbepoetin. Blood and urine samples of the patient were obtained with informed consent. The ethics committee of the Palacky University Hospital approved the study. Darbepoetin was administered as a subcutaneous injection beginning at a dose of 100 μg (1.67 μg/kg) every week and continued for 3 months. There was a 3-month break in therapy, and darbepoetin was reinstituted at a dose of 200 μg weekly, where it remained throughout the course of the study. Hepcidin assay was performed as previously described5 and urine hepcidin concentration was expressed as nanograms hepcidin per milligrams creatinine. Normal ranges for hematologic parameters are as follows: serum iron level, 14.5-26 μM/L; total iron-binding capacity (TIBC), 44.8-71.6 μM/L; ferritin level, 20-150 μg/L (20-150 ng/mL); hemoglobin level, 120-155 g/L (12-15.5 g/dL); and urine hepcidin level, 10-200 ng/mg creatinine.