Erythroleukemia in a renal transplant recipient

A 53-year-old male developed acute erythroleukemia three years after renal transplantation. He had received three years of immunosuppressive therapy with azathioprine. A preleukemia phase associated with chromosome abnormalities was recognized. Azathioprine has been associated with chromosome abnormalities. The chronic stimulation of an abnormal erythroid clone by transplantation may have hastened the development of erythroleukemia.