Serum Epo in Polycythaemia and after Treatment

Serum erythropoietin (S-Epo) was measured with a radiommunoassay method in 36 patients with polycythaemia vera, 17 patients with secondary polycythaemia and 14 patients with relative polycythaemia. The diagnoses were made without the aid of the S-Epo values. It was found that Sment to normal haematocrit levels. the S-Epo levels remained subnormal in most of the polycythaemia vera patients even after 18 months at a haematocrit around 45%. Two patients who had been kept at normal haematocrit for 6 and 7 years both had subnormal S-Epo.