Plasma erythropoietin activity before and after renal homotransplantation in humans.

Plasma erythropoietin levels were determined by Keighley's method to study the changes in erythropoiesis before and after human renal homotransplantation. Results. Erythropoietin titres in pre-transplant patients were low, while they returned to normal after successful renal transplantation. In acute rejection they were significantly high. After its reversal normal levels of erythropoietin were obtained in accordance with a normalization of the graft functions. Reticulocyte counts paralleled with erythropoietin values. Conclusion. High levels of plasma erythropoietin contribute to the diagnosis of acute rejection. Normalization of the plasma erythropoietin levels after the acute rejection could be regarded as an indication for good function of the graft. The grafted kidneys seem to function in producing erythropoietin.