Pathology of lung, upper airways and pleura

Bronchial asthma

• grossly: bronchial occlusion by thick mucus plug
• microscopically:
• mucus
• Curshmann spirals, eosinophils, Charcot-Leyden crystals
• bronchial wall
• edema + hyperemia
• inflammation – eosinophils, basophils, macrophages, lymphocytes (Th2 subset)
• hypertrophy of submucosal mucous glands
• thickened basement membrane
• hypertrophy / hyperplasia of SMCs

Emphysema

• = permanent enlargement of airspaces distal to terminal bronchioles due to destruction of their walls
• smoking
• pathogenesis
• oxidant-antioxidant imbalance
• protease-antiprotease imbalance
• α1-antitrypsin deficiency
• dyspnea + prolonged expiration
• barrel-chested patients

Emphysema

• 1. centriacinar emphysema
• only respiratory bronchioles affected
• upper lobes
• smoking
• 2. panacinar emphysema
• respiratory bronchioles + alveoli affected
• lower lobes
• α1-antitrypsin deficiency
• G: pale voluminous areas
• Mi: thining / destruction of alveolar walls  large airspaces

Emphysema

• complications
• respiratory failure
• pulmonary hypertension  right-sided heart failure
• related conditions
• compensatory emphysema
• senile emphysema / hyperinflation
• obstructive emphysema
• mediastinal emphysema

Chronic bronchitis

• = persistent productive cough for 3 consecutive months in 2 consecutive years
• smoking, air pollutants
• several forms:
• simple CB
• mucopurulent CB
• asthmatic CB
• obstructive CB

Chronic bronchitis

• basis: hypersecretion / hypertrophy of bronchial mucous glands + inflammation
• grossly
• mucosal hyperemia + edema
• mucous / mucopurulent secretion in lumen
• microscopy
• enlargement of mucus-secreting glands (Reid index)
• squamous metaplasia
• mononuclear inflammation
• bronchioles
• goblet cells metaplasia + wall fibrosis