If you encounter a normochromic and normocytic anemia in a diabetic patient, do not forget that it may be a case of erythropoietin deficiency. This deficiency can occur early in diabetic nephropathy (well before stage 5 of chronic kidney disease). In adults, about 85-90% of the erythropoietin comes from the kidneys and 10-15% from the liver. It is produced by interstitial cells in the peritubular capillary bed of the kidneys and by perivenous hepatocytes in the liver. In cases of decreased renal mass, the level of erythropoietin falls and does not increase much in response to hypoxia (anemia). This occurs even if the liver is normal as the latter cannot compensate for the kidney's loss of function. Since the availability of recombinant human erythropoietin to patients in 1989, anemia and transfusion requirements have become relatively rare in patients on hemodialysis. After adequate treatment with erythropoietin, studies have demonstrated that there is an: 1) enhanced exerci