Alpha-1-Antitrypsin Variants in Bronchial Asthma in Kuwait

Abstract

Serum α₁-antitrypsin (α₁AT) levels and protease inhibitor (PI) phenotypes were determined in 176 patients with bronchial asthma. The results were compared with 121 nonasthmatic controls. In the bronchial asthma group, 144 patients (81.8%) had M phenotype, compared to 118 (97.5%) in the controls. Severe deficiency of α₁AT associated with Z phenotype were found in 18 patients (10%), compared to 2 (1.6%) in the controls. Intermediate deficiency associated with MZ and FZ phenotypes were found in 9 (5%) patients with bronchial asthma. MS phenotype was found in 2, MI in 2, and FM in 1 patient with bronchial asthma. The severely deficient group of asthmatics with Z phenotype was found to be heterogenous in clinical presentation. When compared to the asthmatic patients with M phenotype, no statistically significant difference was found between the two groups regarding the type of asthma, severity of the disease, steroid dependency, smoking habits or age at onset. The finding that deficient phenotpyes were more frequent in the asthmatic group suggests that this may be an important contributing factor in the development of bronchial asthma. Exaggerated immunologic and inflammatory responses in such patients, together with the harsh environmental conditions prevailing in Kuwait, may lead to the development of bronchial asthma in subjects deficient in α₁AT.