Beta-thalassemia and pulmonary function.
OBJECTIVE
The survival of patients with beta-thalassemia major 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 pathophysiology of any lung damage is less clearly understood. We studied lung function changes in 32 patients with beta-thalassemia.


METHODS
Respiratory function tests, CO diffusion and arterial blood 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 investigations were performed 24 hours before the patients received a blood transfusion or when they were in a stable state hematologic condition. Echocardiography 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, FVC, FEV1 and RV) in most patients with beta-thalassemia major, indicating a restrictive type of dysfunction. The pulmonary function of patients with beta-thalassemia intermedia seemed to be preserved. Arterial blood gas values were within the normal range, while in some subjects CO diffusion approached the lower limits of normality. There was no evidence that the observed abnormalities in pulmonary function were secondary to congestive heart failure.


CONCLUSIONS
Iron deposition due to repeated blood transfusions may play a central role in determining lung alterations although the majority of patients are well chelated, suggesting that more than one causal mechanisms could be involved.
Piatti
G
G
Ospedale Maggiore di Milano, Pad. Litta, via F. Sforza 35, Milan, Italy.
Allegra
L
L
Ambrosetti
U
U
Cappellini
M D
MD
Turati
F
F
Fiorelli
G
G
D000293:Adolescent; D000328:Adult; D001944:Breath Tests; D002245:Carbon Dioxide / Q000097:blood; D002248:Carbon Monoxide / Q000032:analysis; D015913:Chelation Therapy; D003676:Deferoxamine / Q000627:therapeutic use; D005260:Female; D005541:Forced Expiratory Volume; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007502:Iron Chelating Agents / Q000627:therapeutic use; D019190:Iron Overload / Q000097:blood / Q000188:drug therapy / Q000209:etiology; D008168:Lung / Q000503:physiopathology*; D008297:Male; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D014109:Total Lung Capacity; D014797:Vital Capacity; D017086:beta-Thalassemia / Q000097:blood / Q000150:complications* / Q000503:physiopathology
D006454:Hemoglobins; D007502:Iron Chelating Agents; D002245:Carbon Dioxide; D002248:Carbon Monoxide; D003676:Deferoxamine; D010100:Oxygen