Childhood asthma and allergic rhinitis: the role of leukotrienes.

Research in the past two decades has shown that patients with asthma and rhinitis have inflammation of the involved tissues. This perception has been reflected in recent treatment guidelines, which stress the decreased use of symptom-based therapy and increased use of antiinflammatory therapies to control underlying inflammation. Corticosteroids are the most effective drugs currently in use; however, their use may be limited by potential problems with safety and patient/family adherence, which includes the "fear factor." In addition, the use of high doses of topical corticosteroids (especially when used in both the nose and airways) may have adverse effects when used continuously for long periods. The inflammatory response is complex, involving numerous inflammatory mediators and cells that interact in complicated and interrelated pathways. This provides researchers with numerous interactions at which molecular intervention may result in the attenuation of inflammation, and thus clinical disease. The leukotrienes, a group of important inflammatory mediators, cause vascular leakage and tissue edema; they also promote mucus secretion and a potent bronchoconstriction in patients with asthma. Currently a number of antileukotriene drugs have been developed and preliminary research indicates that they may provide clinicians with a non-steroidal antiinflammatory therapy that may provide steroid-sparing effects. This review examines the leukotrienes and the effects of antileukotriene agents in patients with asthma and allergic rhinitis.