Pulmonary and platelet function in mild form of Hb H disease

Pulmonary function abnormality, arterial hypoxemia and platelet hyperaggregation were commonly seen in severe or moderately severe thalassemic patients. In previous studies, these abnormalities were found in beta-thalassemia, beta-thalassemia/Hb E disease and Hb H disease in 62, 40 and 52%, respectively. However these functional abnormalities in mild form of Hb H disease have not yet been reported. Pulmonary function test by using standard spirometry, platelet aggregation and arterial blood gases were performed in 23 children with mild form of Hb H disease, whose age ranged from 6-18 years (average 11 years), and hematocrit status was 30-40%. Mild to moderate degree of restrictive lung disorder was found in 48% of these patients, 5% had mild platelet hyperaggregation and none of these had arterial hypoxemia. This study showed that a pulmonary function defect was noted as one significant finding in thalassemic patients, being noted even in the very mild form and early age of life. This information will lead to further exploration of the pathogenesis of pulmonary function defects as well as their role is the patients' future health and prognosis.