Pulmonary function in children with transfusion-dependent thalassemia and its relation to serum ferritin

Abstract

Background: Beta thalassemia (β-thalassemia) is one of the most frequent hemoglobinopathies worldwide, with 1.5% of the global population being heterozygotes (carriers) and an incidence of 1/100,000 individuals for symptomatic cases. Regular blood transfusion increases the iron load with documented effects on various body functions; however, the effect on pulmonary function has yet to be established.

Objective: To assess pulmonary function among children with transfusion-dependent thalassemia (TDT) and its relation to serum ferritin levels.

Methods: 67 children with TDT were enrolled in this cross-sectional descriptive study from the Hematology Outpatient Clinic of Alexandria University Children’s hospital (Alexandria, Egypt). Patients included 39 males (58.2%), age (range: 6.7-17.5, mean: 10.86) years. A spirometry test was performed, and data were expressed and interpreted using the Z-scores. Laboratory studies included pre-transfusion hemoglobin and serum ferritin.

Results: Although children with TDT were all clinically asymptomatic, 32.8% had an abnormal spirometric pattern. Restrictive impairment was the predominant pulmonary dysfunction (28.4%) with higher age and serum ferritin level being the two predictor factors. Spirometric lung volumes (FVC and FEV₁) were negatively correlated with the age of patients and the level of body iron stores measured by serum ferritin.

Conclusion: Restrictive pulmonary dysfunction in patients with TDT can be related to the degree and duration of iron overload, which might reflect the role of iron deposition and accumulation in the pathogenesis of pulmonary dysfunction in these patients.