Effect of inhaled corticosteroids on small airway inflammation in patients with bronchial asthma

Bronchial asthma is a chronic inflammatory disease affecting the bronchial mucosa. In asthma patients, the highest number of inflammatory cells, including eosinophils, are found in the small bronchi. According to the most recent 2006 report of the Global Initiative for Asthma, inhaled corticosteroids (ICS) remain the first‑line treatment of chronic asthma. They are characterized by high lung deposition and good distribution in the small bronchi, which makes them particularly efficient in reducing chronic inflammatory infiltrate in the small airways. Good pulmonary distribution of ICS in patients with mild asthma is reflected by a better control of the disease, improvement in the quality of life, improvement in the results of pulmonary function tests, decreased levels of exhaled proinflammatory nitric oxide, lower number of inflammatory cells (including eosinophils) in the induced sputum, decrease in bronchial hyperreactivity, and decrease in exhaled air trapping observed in the computed tomographic scanning of the lungs.