Pulmonary Dysfunction in Thalassemia Major Patients.

The improved survival of patients with Thalassemia Major (TM) has allowed new complications to develop in the adult patients. These previously unknown clinical entities require a new approach to the management of thalassemia. Pulmonary dysfunction is one of the least understood, previously unrecognized, complications of TM.

Patients and Methods The aim of our study was to define the spirometric pattern and lung damage in 35 TM patients (18 M and 17 F, age range from 18 to 44 years). All were regularly transfused (pre transfusion hemoglobin level 9+/−0,4 g/dl) and chelated (25 with deferoxamine,5 with deferiprone and 5 with both chelators). Their serum ferritin level was 1071+/−628 ng/ml All patients had normal cardiac ejection fraction. Nine patients were active smokers (10+2 pack/years) while 9 had been smokers in the past (6+2 pack/years). Four had a mild allergic asthma under good clinical control, 1 had a mild pulmonary hypertension and 1 had mediastinal hematopoietic tissue. Pulmonary function tests were performed before transfusion and included pulmonary volumes and flows recorded by spirometry; residual volume (RV) and total lung capacity (TLC)measured by helium closed-circuit rebreathing technique; carbon monoxide diffusion capacity (TLCO)measured by single breath method.

Results: Only the patient with mediastinal masses showed an obstructive pattern with the FEV1/FVC ratio of 53% of predicted value. Thirteen patients (37%)had a restrictive pattern (TLC<80%pred). No correlation was found with sex, age, smoking, asthma diagnosis, ferritin levels, chelation regimen. A decreased TLCO (<70%pred) that can be indicative of parenchymal disease was present in 29 patients (85,8%) even after correction for hemoglobin levels (Hb value equal to 12 g requires adjust of 8%, Hb value equal to 10 g requires adjust of 18%, Hb value equal to 7 g requires adjust of 45%). The restrictive lung function abnormality with reduced diffusion capacity found in our patients is suggestive of interstitial lung disease secondary to TM. We were unable to correlate the restrictive and interstitial lung disease to iron loading nor to chelation strategies. Further studies are needed to better understand these results and to determine whether different chelation regimens have different impact on pulmonary function. In order to minimize lung damage, however, every effort should be made to educate TM patients not to smoke, and to identify and properly treat TM patients with asthma.