Phlebotomy to Reduce Iron Overload in Patients Cured of Thalassemia by Bone Marrow Transplantation

Abstract

In thalassemia after successful bone marrow transplantation (BMT), iron overload remains an important cause of morbidity. After BMT, patients have normal erythropoiesis capable of producing a hyperplastic response to phlebotomy so that this procedure can be contemplated as a method of mobilizing iron from overloaded tissues. A phlebotomy program (6 mL/kg blood withdrawal at 14-day intervals) was proposed to 48 patients with prolonged follow-up (range, 2 to 7 years) after BMT. Seven patients were not submitted to the program (five because of refusal and two because of reversible side effects). The remaining 41 patients (mean age, 16 +/- 2.9 years) were treated for a mean period of 35 +/- 18 months. All were evaluated before and after 3 +/- 0.6 years of follow-up. Values are expressed as mean +/- standard deviation (SD) or as median with a range (25 to 75 percentile). Serum ferritin decreased from 2,587 (2,129 to 4,817) to 417 (210 to 982) microg/L (P < .0001), total transferrin increased from 2.34 +/- 0.37 to 2.7 +/- 0.58 g/L (P = .0001), transferrin saturation decreased from 90% +/- 14% to 50% +/- 29% (P < .0001). Liver iron concentration evaluated on liver biopsy specimens decreased from 20.8 (15.5 to 28.1) to 4.2 (1.6 to 14.6) mg/g dry weight (P < .0001). Aspartate transaminase decreased from 2.7 +/- 2 to 1.1 +/- 0.6 (P < .0001) and alanine transaminase from 5.2 +/- 3.4 to 1.7 +/- 1.2 (P < .0001) times the upper level of normality. The Knodell score for liver histological activity decreased from 6.9 +/- 3 to 4.9 +/- 2.8 (P < .0001). These data indicate that phlebotomy is safe, efficient, and widely applicable to ex-thalassemics after BMT.