3.2. Trial design Day 0 Consent form signed Patients randomly allocated to control or treatment groups (20000 and 40000 IU) Serum Cystatin C determination Serum Creatinine determination Urinary NGAL determination Administration of intravenous rhu Epo on Day 0 or no Epo (control group) Day 2 At 48 hr after rhu EPO injection, samples will be taken for