FOLIC-ACID SUPPLEMENTATION IMPROVES ERYRTHROPOIETIN RESPONSE

Therapy with recombinant human erythropoietin (rhEPO) has become most valuable for the treatment of renal anemia in patients with various ch ronic renal diseases, For the first time this study presents data show ing that rhEPO affects the metabolism of folic acid, There were 13 pat ients enrolled; they suffered from different chronic renal diseases an d showed an impaired responsiveness to rhEPO therapy, Before starting rhEPO therapy the mean corpuscular volume of erythrocytes (MCV) was me asured; MCV was 90.4 fl. During rhEPO therapy the MCV increased signif icantly by 14.8 fl (p < 0.05). The developing macrocytic anemia was ov ercome when folic acid was administered additionally for a mean period of 3.14 +/- 3 months, Hematocrit (Hct) also responded accordingly, Wh ereas Hct did not increase adequately during the exclusive treatment w ith rhEPO, an increase in Hct from 2.3 +/- 3.3 to 30 +/- 4.2% (p < 0.0 1) was observed after the addition of folic acid, These results are ra ther remarkable as folic acid serum levels were clearly within the nor mal range during the whole study period, So it can be concluded that r hEPO therapy results in an increased demand for folic acid. Even if se rum concentrations are within the normal range, the administration of folic acid will enhance the effectiveness of rhEPO therapy so that the rhEPO dosage can be reduced.