Pathogenesis of Asthma, and Its Macroscopic & Microscopic Presentation
Pathogenesis of Asthma, and Its Macroscopic & Microscopic Presentation What Is Asthma? Asthma is a chronic inflammatory disease of the airways characterized by reversible airflow obstruction , bronchial hyperresponsiveness , and airway inflammation . It affects both children and adults and can be triggered by allergens, infections, exercise, or irritants. Pathogenesis of Asthma The pathogenesis of asthma is complex and involves genetic , environmental , and immune system factors . Here is a step-by-step explanation: 1. Trigger Exposure Common triggers: allergens (dust mites, pollen), respiratory infections, cold air, exercise, smoke, and pollution. 2. Immune System Activation In atopic (allergic) asthma , exposure to allergens leads to activation of Th2 CD4+ T cells . These Th2 cells release: IL-4 promotes IgE production by B cells. IL-5 activates eosinophils. IL-13 promotes mucus secretion and IgE production. 3. Mast Cell Degranulation ...