Clinical meaning
Asthma is chronic inflammatory disease driven by Th2 immune response producing IL-4 (IgE switching), IL-5 (eosinophil recruitment), IL-13 (mucus, hyperresponsiveness). IgE cross-linking triggers mast cell degranulation. Stepwise therapy: Step 1-2 = PRN ICS-formoterol; Step 3 = low-dose ICS-LABA; Step 4-5 = medium-high ICS-LABA +/- LAMA +/- biologic.
Diagnosis & workup
Diagnostics & workup: - Chest X-ray PA and lateral (infiltrates, hyperinflation, effusions) - Thoracentesis with Light criteria for pleural effusion classification - 6-minute walk test for functional capacity assessment - Pulse oximetry and continuous SpO2 monitoring - CT chest high-resolution for interstitial/parenchymal disease - Peak expiratory flow rate monitoring for asthma - CT pulmonary angiography for PE evaluation
Risk factors: - Indoor air pollution and biomass fuel exposure - Prematurity with bronchopulmonary dysplasia history - Connective tissue disease with ILD predisposition - Obesity with restrictive physiology and OSA - Family history of alpha-1 antitrypsin deficiency - Age >65 with declining mucociliary clearance - Childhood asthma with persistent airway hyperreactivity