| Abstract: | Summary To investigate whether serum erythropoietin (EPO) levels are influenced by the intensity of bone marrow erythroid activity, we used a radioimmunoassay (Nippon DPC Co., Japan) to study EPO levels in three acute leukaemia patients during treatment with intensive chemotherapy. We also measured the reticulocyte count and reticulocyte maturity using an automated reticulocyte analyser (Sysmex R-2000) to detect erythropoietic activity. From the day after the initiation of chemotherapy, EPO levels increased markedly without any change in Hb levels, suggesting that some other mechanism was regulating serum EPO. A decrease in EPO after chemotherapy was accompanied by an increase in high fluorescence ratio, an index of immature reticulocvtes, but the actual increase in the reticulocyte count was delayed for 3-4 days after this. These findings suggest that the decrease in serum EPO levels was closely related to the early stage of red cell production and that EPO levels may be a useful marker for the recovery of erythropoietic activity after chemotherapy. |
