Hb E thalassemia in Sri Lanka.

Pulmonary function tests were performed on 30 patients with beta-thalassemia/Hb E. Only one patient had normal pulmonary function. Arterial hypoxemia at rest was present in 22 of 30 patients (73.3%). Abnormal VC, FEV1, FEV1/FVC, and end tidal FEV1 were found in 29 (96.7%), 17 (56.7%), 6 (20.0%), and 17 (56.7%) patients, respectively. Single-breath carbon monoxide diffusing capacity was abnormal in one out of 11 patients (9.1%). These results suggest the presence of abnormal ventilatory function included restrictive, obstructive, and combined defects. The hypoxemia in thalassemia was probably due to ventilation/perfusion mismatch and a diffusion defect.