beta-thalassemia and pulmonary function

Background and Objective. The survival of patients with beta-thalassemia ma jor and intermedia has improved considerably. This has focused attention on the long-term sequelae of the disease itself and its treatment. The effect of hemosiderosis in major organs (heart, liver, etc) are well-recognized, but the pathophyisology of any lung damage is less clearly understood. We s tudied lung function changes in 32 patients with beta-thalassemia. Design and Methods. Respiratory function tests, CO diffusion and arterial b lood gas analysis were performed on 19 patients with beta-thalassemia major (9 F, 10 M) and 13 with beta-thalassemia intermedia (6 M, 7 F). All invest igations were performed 24 hours before the patients received a blood trans fusion or when they were in a stable hematologic condition. Echocardiograph y was performed in all patients and the ejection fraction was employed as a measure of cardiac function. Results. No patient had clinical signs of pulmonary dysfunction. Pulmonary function tests, however, showed a reduction of all main parameters (TLC, RI G, FEV1 and RV) in most patients with beta-thalassemia major, indicating a restrictive type of dysfunction. The pulmonary function of patients with be ta-thalassemia intermedia seemed to be preserved. Arterial blood gas values were within the normal range, while in some subjects CO diffusion approach ed the lower limits of normality. There was no evidence that the observed a bnormalities in pulmonary function were secondary to congestive heart failu re. Interpretation and Conclusions. Iron deposition due to repeated blood trans fusions may play a central role in determining lung alterations although th e majority of patients are well chelated, suggesting that more than one cau sal mechanism could be involved. (C) 1999, Ferrata Storti Foundation.