Background: Thalassemia major (TM) is a chronic disease requiring regular transfusions that may result in generalized iron loading, such as in the heart, the liver, endocrine organs, and the lungs. We aimed to determine pulmonary function abnormalities in children with TM in our center.
Patients and methods: In this study, pulmonary function tests (PFTs) of 49 patients with TM who received regular blood transfusion and had no history of chronic respiratory disease were evaluated. The relationship between PFTs and the age, the body surface area, pretransfusional hemoglobin, and serum ferritin was evaluated.
Results: Among the β-TM patients included in this study, 61% were male and 39% were female, with a mean age of 10.8±3 years (range, 5 to 17 y). The patients' mean level of ferritin was 3873±2011 ng/dL (range, 676 to 9476 ng/dL). A reduced forced vital capacity (FVC) was found in 33 patients (67%). A reduced forced expiratory volume in 1 second (FEV1) was found in 15 patients (30%). A forced expiratory volume in 1 second to forced vital capacity (FEV1/FVC) ratio of >80% was found in all patients. The peak expiratory flow (PEF) was decreased in 23 patients (46.9%). The forced mid-expiratory flow between 25% and 75% of the exhaled vital capacity (MEF25%-75%) was decreased in 5 patients (10%). FVC and FEV1 values in patients with a high ferritin level (>2500 ng/dL) were decreased compared with patients with a low ferritin level (<2500 ng/dL) (P=0.04, 0.03). FVC, FEV1, and PEF parameters were negatively correlated with the age and the body surface area. Age was a predictor of FVC (β=-0.450, P<0.001), FEV1 (β=-0.419, P<0.001), and PEF (β=-0.505, P<0.001), and hemoglobin was a predictor of FEV1/FVC (β=0.366, P=0.01) and MEF25%-75% (β=0.323, P=0.003).
Conclusions: Our results concluded that the respiratory system should be evaluated by PFTs even in asymptomatic patients with high serum ferritin levels during the adolescent period annually to prevent the squeal of pulmonary disease in TM. Patients who have abnormal PFTs should be reevaluated for compliance with chelation therapy and the transfusion program.