Asthma is a chronic inflammatory disorder of the airways characterized by recurring episodes of reversible airway obstruction, hyper-responsiveness, wheezing, breathlessness and coughing. Clinical diagnosis of asthma ...Asthma is a chronic inflammatory disorder of the airways characterized by recurring episodes of reversible airway obstruction, hyper-responsiveness, wheezing, breathlessness and coughing. Clinical diagnosis of asthma is based on the pattern of clinical symptoms and pulmonary fuction tests. Asthma affectes 5% - 10% of the population and the number of worldwide cases is approximately 300 milliones. The incidence of this disease is increasing particulry in western countries [1]. It is the cause of a huge economic burden to national healthcare services. In a minority of cases, asthma is potentially fatal. After a period when fatalities appeared to be increasing [2], in recent years asthma-related mortality has progressively declined due to the develop- ment of specific asthma disease management programs, as well as the extensive use of in- haled corticosteroids [3]. Inflammation of the airways is a central component in asthma. In- flammation is associated with infliltration of the airway wall with eosinophiles and or neutron- philes mast cell degranulation and T cell active- tion. Other pathological features include, sub- basement membrane thickening, loss of epithet- lial cell integrity, goblet cells hyperplasia In- crease in airway smooth muscle mass. Eosino- phils are thought to be vital in the development of airway hyperreactivity, with the eosinophil cationic protein playing a crucial role [4]. The fact that treatment of asthma with corticos-teroids reduces eosinophils numbers and decreases airway reactivity further supports this hypothesis.展开更多
文摘Asthma is a chronic inflammatory disorder of the airways characterized by recurring episodes of reversible airway obstruction, hyper-responsiveness, wheezing, breathlessness and coughing. Clinical diagnosis of asthma is based on the pattern of clinical symptoms and pulmonary fuction tests. Asthma affectes 5% - 10% of the population and the number of worldwide cases is approximately 300 milliones. The incidence of this disease is increasing particulry in western countries [1]. It is the cause of a huge economic burden to national healthcare services. In a minority of cases, asthma is potentially fatal. After a period when fatalities appeared to be increasing [2], in recent years asthma-related mortality has progressively declined due to the develop- ment of specific asthma disease management programs, as well as the extensive use of in- haled corticosteroids [3]. Inflammation of the airways is a central component in asthma. In- flammation is associated with infliltration of the airway wall with eosinophiles and or neutron- philes mast cell degranulation and T cell active- tion. Other pathological features include, sub- basement membrane thickening, loss of epithet- lial cell integrity, goblet cells hyperplasia In- crease in airway smooth muscle mass. Eosino- phils are thought to be vital in the development of airway hyperreactivity, with the eosinophil cationic protein playing a crucial role [4]. The fact that treatment of asthma with corticos-teroids reduces eosinophils numbers and decreases airway reactivity further supports this hypothesis.
