ASSESSMENT OF AIRWAY RESISTANCE AND INFLAMMATION IN PATIENTS WITH BETA THALASSEMIA MAJOR

Abstract

SUMMARY B eta thalassemia major is the most common hemoglobinopathies in our region with treatment of regular blood transfusion. It is characterized by abnormal hemoglobin synthesis, which result in decreased oxygen delivery to tissues, ineffective erythropoiesis and iron overload. Iron overload and hemosiderosis can cause organ damage and also it is the main cause of lung pathophysiology in thalassemic patients. Neutrophil chemotactic and functional defects occurs in β-thalassemia major. IL-8is a novel chemotactic and activating peptide for neutrophils and can be detected in the circulation. IL-8 serum concentration were elevated in thalassemic patients, so it considered the inflammatory marker in their serum. Lung impairment represents one of the complications of thalassemia major whose clinical picture can remain in subclinical form all life long, so follow up of β- thalassemia major patients regularly with IOS for early detection of small airway affection is needed. Impulse oscillometry has been successfully used to measure lung function in children with high degree of sensitivity and specificity to small airway impairments. IOS measures of airway function and equivalent electrical circuit models of the human respiratory system have been developed to quantify the severity of the condition. In view of these data, this study aimed to assay airway resistance and inflammation in patients with Beta-thalassemia major by measuring IL-8 as a marker of inflammation and impulse oscillometry to investigate lung impairment. The study included 60 patients with β-thalassemia major. 15 patients were on mono chelation therapy and 45 patients were on combined therapy. Patients were compared with 30 age and sex matched healthy subjects served as controls. The control group consisted of 17(56.7%) males and 13(43.3%) females. The mean age of thalassemia patients was 9.43 ±3.25 years (ranged 5-17 years) while that of control was 9±3.26 (ranged 5-17years). All included patients were subjected to detailed medical history and through clinical examination with special emphasis on disease duration, anthropometric measures, blood pressure, history of splenectomy, transfusion history and chelation therapy. Laboratory investigations included mean serum hemoglobin in the last year, mean serum ferritin in the last year, plasma IL-8 concentration by ELISA. In the current work it was found that the mean serum ferritin among the studied patients which was calculated in the last year ranged from (462-1012µg/L) with median2091(1156-2467.2µg/ L) and around 12 patients (20%) had mean serum ferritin more than 2500µg/L. Analysis of serum IL-8 of the studied patients revealed that there was a high statistical significant difference between patients and control group as regards IL-8 concentration as it ranged from (1o.43-55.78pg/µg) with mean 24.7 and SD(±10.39). Pulmonary function test was done on 60 thalassemia major patients with blood transfusion by using IOS. IOS test was normal in 48 patients (80%), obstructive airways in 6 patients (10%) and restrictive airways in 6 patients (10%). We concluded that the abnormalities in IOS test of studied patients with β-thalassemia major on regular blood transfusion showed that small airway disease was predominant abnormality in thalassemia patients, obstructive and restrictive pattern are equally in distribution among our studied patients. Further studies including large number of patients are required to validate our results.