ANEMIA AND ERYTHROPOIETIN LEVELS IN LUNG-TRANSPLANT RECIPIENTS

An evaluation of 26 surviving outpatient lung transplant recipients at one center showed that 65% (17/26) had significant anemia (hemoglobin <11 g/L for women, <14 g/dl for men) at a median follow-up of 13.5 mo nths after transplantation (range, 1-41 months). There were 14 men and 12 women with a mean age of 45.1 years (range, 23.1-66.7 years). Fift een had a double allograft and 11 had a single allograft. Anemia was n ormochromic and normocytic/macrocytic with a tendency to anisocytosis, with normal reticulocyte counts. Iron deficiency (transferrin saturat ion <20%) was found in 35% (6/17) of anemic patients, and two of them also had ferritin levels <15 mu g/L. In addition, vitamin B12 was decr eased in 1 patient. Folate levels were all normal. Erythropoietin leve ls were significantly decreased in anemic lung transplant recipients a s compared with nontransplanted iron-deficient anemic patients (median , 1 mU/ml, range 1-41 mU/ml, vs. 53 mU/ml, 15-88 mU/ml; P<0.05). In no nanemic lung transplant recipients, erythropoietin levels were decreas ed too, as compared with normal controls (median, 2 mU/ml, range 1-21 mU/ml, vs. 5 mU/ml, 3-32 mU/ml; P<0.05). Investigation of peripheral s tem cells in 9 patients showed normal stimulation of erythroids (burst -forming unit, erythroid; median, 573 cells/ml; range, 128-1898 cells/ ml) independent of erythropoietin concentrations. Analysis of putative prognostic factors, such as age, surgical procedure (double vs. singl e lung allograft), indication for transplantation, time after transpla ntation, infection status, presence of bronchiolitis obliterans, immun osuppression (+/- azathioprine), serum creatinine, creatinine clearanc e, hypertension, and arterial partial pressure of oxygen, did not demo nstrate any difference in erythropoietin concentrations. Only the sex variable revealed a trend to higher levels in women than in men (media n, 4 mU/ml, range 1-41 mU/ml, vs. 1 mU/ml, 1-16 mU/ml; P>0.05). The ca uses for low erythropoietin levels are not quite understood yet; howev er, they offer a rationale for the treatment of chronic anemia with re combinant human erythropoietin.