Polycythemia after kidney transplantation: influence of the native kidneys on the production of hemoglobin.

3 patients with renal transplantation who developed polycythemia presented normalization of the hemoglobin levels immediately after nephrectomy of the native kidneys. This observation induced the authors to study the role of the native kidneys in the genesis of polycythemia in recipients of renal allografts. Comparison was made among 32 patients submitted to renal transplantation, with maintenance of native kidneys (group I) and among 31 under the same conditions, but without the native kidneys (group II). Both groups were comparable according to age, sex, rejection crisis incidence and immunosuppressive therapy. It was observed that the hemoglobin levels of group I were significantly higher (p less than 0.05 to p less than 0.005) than those observed in group II, from the 3rd to the 30th posttransplantation month, becoming comparable from the 36th to the 54th months. The hemoglobin production, measured by the kinetics of labeled iron (59Fe), was higher in patients of group I. The authors concluded that the native kidneys are responsible for the observed polycythemia after a kidney transplantation.