Post-transplant erythrocytosis: a disease with multifactorial etiology

Post-transplant erythrocytosis (PTE) is defined as an increase in hematocrit greater than 51%. This phenomenon affects 5 to 17% of renal transplant patients within two years of transplantation. Its etiology is not clearly known, but several factors have been implicated in its pathogenesis. We report on a 50-year-old male, known to have autosomal dominant polycystic kidney disease, diabetes mellitus and hypertension for 20 years, who underwent a living unrelated donor transplantation. Three years following renal transplan-tation, he was noted to have high hemogloblin and hematocrit (18.3 gm%, 53.8%). This erythrocytosis persisted for nine months during which period he underwent multiple phlebotomies before undergoing spontaneous remission. He did not develop any compli-cations of erythrocytosis. Our patient had multiple factors to account for occurrence of PTE: diabetes mellitus, hypertension, mild allograft dysfunction, polycystic kidney disease and cyclosporin therapy. Our case suggests that multiple factors may be operative in a given patient leading to the development of PTE.