Corticosteroids are highly effective anti-inflammatory drugs in the treatment of asthma. The clinical efficacy of these drugs is thought to result from a combination of effects on lung inflammation.<sup>18 de Benedictis F.M., Canny G.J., Levison H. The role of corticosteroids in respiratory diseases of children Pediatr Pulmonol 1996 ;  22 : 44  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti, 64 Schwiebert L.M., Beck L.A., Stellato C. , e al. Glucocorticosteroid inhibition of cytokine production: Relevance to antiallergic actions J Allergy Clin Immunol 1996 ;  97 : 143  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti</sup> These include immunosuppressive effects on inflammatory cell trafficking into the lung, reduction of inflammatory cell survival, diminished airway mucus production, an inhibitory effect on inflammatory cytokines, and other anti-inflammatory mechanisms, including the increased gene transcription of anti-inflammatory proteins. Asthmatic patients, however, vary in their responses to corticosteroids. Although most patients respond to regular inhaled corticosteroid therapy, a small proportion of asthmatic patients have poorly controlled asthma even when treated with high doses of oral prednisone or its equivalent. These patients account for a large proportion of the hospitalizations and emergency room visits caused by asthma. Therefore, a disproportionate amount of health care resources is spent on this small subset of patients.

This article reviews the current understanding of the molecular and cellular mechanisms underlying corticosteroid-insensitive asthma. The mechanisms that give rise to corticosteroid insensitivity have important clinical implications for the management of severe asthma and other allergic disorders characterized by tissue inflammation. It is important to evaluate these patients carefully to confirm the diagnosis of asthma and to identify potentially correctable concomitant conditions that may confound their asthma. Once a diagnosis of corticosteroid-insensitive asthma has been made, alternative anti-inflammatory approaches must be considered.