Course 04: Respiratory Medicine and Infectious Disease
Lesson 10 of 14. Explore the diagnostic and management frameworks, work through the case, and finish the linked 10-question practice set. Urgent presentations require an emergency-care pathway and review of local professional scope.
Interstitial lung disease (ILD)
- Progressive exertional dyspnea, dry cough, fine inspiratory crackles and sometimes clubbing suggest fibrotic ILD; investigate autoimmune, drug and occupational causes.
- A restrictive spirometry pattern needs full lung volumes and diffusion capacity; high-resolution CT is central for ILD pattern characterization after appropriate evaluation.
- Progressive hypoxemia, acute deterioration and pulmonary hypertension signs require expedited specialist assessment.
Bronchiectasis and chronic productive cough
- Persistent daily sputum, recurrent infections, crackles and occasional hemoptysis may suggest bronchiectasis; chest CT confirms structural airway dilatation.
- Consider underlying causes including prior infection, immune deficiencies, aspiration, allergic bronchopulmonary aspergillosis and cystic fibrosis in selected patients.
- Airway-clearance techniques, culture-directed antibiotic decisions and vaccination are important; not all chronic sputum means COPD.
Environmental and medication exposures
- Ask about silica, asbestos, birds, mold, farming, construction, biomass, vaping and relevant medications (e.g., amiodarone, certain cancer therapies).
- Hypersensitivity pneumonitis requires exposure assessment plus clinical/imaging correlation; avoid assuming every indoor mold exposure proves ILD.
- Smoking cessation and elimination of harmful exposures are priorities, with occupational medicine/public health coordination as appropriate.
Red flags and multidisciplinary care
- Large-volume hemoptysis or threatened airway is an emergency; chronic blood-streaked sputum still warrants risk-based evaluation.
- Acute ILD exacerbation, resting hypoxemia or rapidly declining functional status requires urgent referral.
- Rehabilitation, oxygen assessment, advanced care planning and multidisciplinary specialist input can improve function and patient-centred care.
Applied clinical case
A 62-year-old construction worker with silica exposure has progressive dyspnea, dry cough, inspiratory crackles and declining exercise tolerance.
Show model clinical reasoning and disposition
Investigate ILD and occupational exposure (PFT with diffusion capacity and appropriate high-resolution CT) and arrange respiratory/occupational referral. Do not assume this is uncomplicated asthma.
Clinical self-check
- How do restriction and obstruction differ?
- Why is occupational history essential?
- What confirms bronchiectasis?
Current guidance and further learning
- Canadian Thoracic Society guideline library (external)
- Choosing Wisely Canada: Respiratory medicine (external)