Asthma is a chronic respiratory disease characterized by reversible airflow limitation and airway hyper-responsiveness to a variety of stimuli. The understanding of the pathogenesis of asthma has evolved from that of a purely bronchospastic disease to one in which airway inflammation plays a central role.<sup>16 Bousquet J., Chanez P., Lacoste J.Y. , e al. Eosinophilic inflammation in asthma N Engl J Med 1990 ;  323 : 1033-1039  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti, 55 Robinson D.S., Hamid Q., Ying S. , e al. Predominant Th2-like bronchoalveolar T-lymphocyte population in atopic asthma N Engl J Med 1992 ;  326 : 298-304  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti</sup> Consequently, there has been a shift from routinely administered bronchodilator therapy to using anti-inflammatory medications earlier in the course of the disease and for patients with less severe asthma. All of the guidelines now recommend an anti-inflammatory agent for all asthmatics except those with mild intermittent asthma.<sup>24 Expert Panel Report I.I. Guidelines for the Diagnosis and Management of Asthma  Bethesda, MD: National Institutes of Health, National Heart, Lung and Blood Institute (1997).  Publication No. xx..

Cliccare qui per andare alla sezione Riferimenti, 27   International Consensus Report on Diagnosis and Treatment of Asthma 1992 Bethesda, MD: National Institutes of Health, National Heart, Lung, and Blood Institute (1992).  Publication No. 92–3091.

Cliccare qui per andare alla sezione Riferimenti</sup> Given that glucocorticoids (GC) have potent anti-inflammatory effects, they constitute the pharmacologic cornerstone of asthma therapy.<sup>64 Szefler S. Glucocorticoid therapy for asthma: Clinical pharmacology J Allergy Clin Immunol 1991 ;  88 : 147-165  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti</sup> Inhaled GCs are among the most effective controller therapies for the management of persistent asthma, and systemic GCs are used primarily as rescue therapy for moderate and severe acute manifestations of asthma. Although the majority of asthmatics respond favorably to GC therapy, a subset of individuals do not. These asthmatics are termed steroid resistant (SR).