Anemia and iron deficiencies among long-term renal transplant recipients.

Iron deficiency anemia after renal transplantation has not been systematically investigated. The prevalence of anemia and the indicators of iron deficiency among 438 renal transplant recipients were examined. Anemia was present in 39.7% of the patients. The prevalence of iron deficiencies, as indicated by a percentage of hypochromic red blood cells (HRBC) of >or=2.5%, was 20.1%. The majority of severely anemic patients exhibited HRBC values in the upper quartile. Positive associations of hemoglobin levels with creatinine clearance, serum transferrin levels, male gender, transferrin saturation (TSAT), polycystic kidney disease, and age were observed. Negative associations with erythropoietin therapy, use of azathioprine, serum ferritin levels, and body mass index were observed. The risk for anemia was closely related to the highest quartile of HRBC percentages (odds ratio, 2.35; 95% confidence interval, 1.48 to 3.75; P = 0.00029), whereas ferritin levels and TSAT conferred no risk for anemia. Therefore, assessment of the HRBC proportion is superior to decreased ferritin and decreased TSAT measurements for the diagnosis of iron deficiencies among renal transplant recipients.