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Asthma . Asthma Is A Disorder Of The Bronchial Mucosa Which

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Asthma
Asthma is a disorder of the bronchial mucosa which causes bronchial hyperresponsiveness. Patients who suffer from asthma have a hyperresponsiveness of the airways which causes narrowing to stimuli that illicit no bronchoconstriction in patients without asthma or airway disease (McCance, 2014). Expert Panel 3 of the National Asthma Education and Prevention Program defines asthmas as “a common chronic disorder of the airways that is complex and characterized by variable and recurring symptoms, airflow obstruction, bronchial hyperresponsiveness, and an underlying inflammation. The interaction of these features of asthma determines the clinical manifestations and severity of asthma and the response to treatment (Fanta, 2017).” …show more content…

Early Asthmatic Response The early asthmatic response is the initial exposure of the antigen to the bronchial mucosa (McCance, 2014). Dendritic cells present the antigen to CD4+ T cells which become Th2 cells which release cytokines. The Cytokines IL-4, IL-5, IL-8, IL-13, IL-17, and IL-22 are released. Antigen specific IgE production is stimulated by IL-4. Il-5 stimulates the proliferation of eosinophils which cause tissue injury and toxic neuropeptides which contribute to hyperresponsiveness, fibroblast proliferation, airway scarring, and epithelial injury. Inflammatory response is exaggerated by neutrophil activation by IL-8. IL-13 reduces mucociliary clearance, enhances fibroblast secretion and helps bronchoconstriction and airway remodeling. Neutrophilic inflammation is increased by IL-17 and IL-22 stimulates airway epithelial cells which stimulate further adaptive immune responses. Degranulation of the mast cells, caused by the Fc portion of IgE binding to receptors on the surface of mast cells, releases inflammatory mediators which cause vasodilation, increased capillary permeability, mucosal edema, bronchial smooth muscle contraction, and mucous secretion of the goblet cells and narrowing of the airways (McCance, 2014).
Late Asthmatic Response The late response asthmatic response is a secondary response where the recruitment of lymphocytes, eosinophils, and neutrophils during an

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