Bronchoconstriction

Wheeze

Common (the "Big 3")

• Asthma
• COPD
• Bronchiolitis (peds)
• CHF ("cardiac asthma")

Airway — Intrathoracic Lower

• Aspirated foreign body
• Bronchiectasis
• Bronchiolitis
• Bronchiolitis obliterans
• Pneumonia (focal wheeze)
• Pulmonary embolism
• Carcinoid tumor
• Endobronchial tuberculosis
• Parasitic infection (eosinophilic pneumonia; in endemic areas)
• Hypersensitivity pneumonitis (e.g., farmer's lung)

Airway — Intrathoracic Central

• Aspirated foreign body
• Tracheal stenosis / tumor
• Tracheomalacia
• Mucus plugging
• Vascular ring / aortic aneurysm
• Mediastinal mass / lymphoma

Airway — Extrathoracic (typically stridor ± wheeze)

• Foreign body
• Anaphylaxis
• Angioedema (including ACE inhibitor-induced)
• Croup
• Epiglottitis
• Vocal cord dysfunction / paradoxical vocal fold motion
• Vocal cord edema / paralysis
• Laryngeal stenosis / tumor
• Retropharyngeal abscess
• Peritonsillar abscess
• Tonsillar / adenoid hypertrophy
• Goiter / thyroid mass
• Postnasal drip

Allergic / Inflammatory

• Anaphylaxis
• Allergic bronchopulmonary aspergillosis (ABPA)
• Eosinophilic granulomatosis with polyangiitis (Churg-Strauss)
• Sarcoidosis

Drug-Induced Bronchospasm

• Beta-blocker (including ophthalmic)
• Aspirin / NSAIDs (aspirin-exacerbated respiratory disease)
• ACE inhibitor (cough / bronchospasm)
• Cholinergic agents (e.g., neostigmine)
• Inhaled irritants / smoke inhalation

Other

• GERD / aspiration
• Pneumothorax (decreased breath sounds ± focal wheeze)
• Pulmonary embolism (may present with wheeze in up to 25%)
• Vocal cord dysfunction (often misdiagnosed as refractory asthma)
• Obesity hypoventilation