Fig. 2

a Constricted large airway, with thickened airway smooth muscle, mucosal congestion and mucus plugging. Observe the widened bronchovascular bundles, with tearing of the connective tissue. b Detail of a large airway showing thickened basement membrane, capillary ectasia and congestion, eosinophilic inflammation and a thick airway smooth muscle bundle, consistent with asthma. c Lung section of a fatal asthma case showing bronchial duct gland ectasia with chronic inflammation, common findings in fatal asthma. PIE - Pulmonary Interstitial Emphysema; BM = Basement Membrane; SM = Submucosa; ASM = Airway Smooth Muscle; * = alveolar hyperdistension, arrow = bronchial duct ectasia