[Serum erythropoietin levels: a new diagnostic tool?]

The development of highly specific antibodies against recombinant human erythropoietin (EPO) has recently made the accurate radioimmunological measurement of serum levels of this hormone possible. In this study we determined the serum-EPO levels in 100 healthy volunteers, in 54 patients suffering from polycythemia vera and in 51 patients with secondary polyglobulia. The mean levels for the healthy group were found to be 11.3 +/- 3.4 mU/ml in females and 8.0 +/- 3.2 mU/ml in males. Patients with polycythemia vera had serum-EPO levels of 4.3 mU/ml, while those with secondary polyglobulia had significantly higher levels averaging 30.3 mU/ml (p less than 0.0001). However, an overlapping of serum-EPO values in the range between 10 and 20 mU/ml occasionally occurs. Our results show that measurement of the serum-EPO level can be useful in the differential diagnosis of polyglobulias. Additionally, sequential EPO level measurements after phlebotomy and after hemorrhage show a pronounced increase in serum-EPO in secondary polyglobulia, while in polycythemia vera the level only increases slightly.