Respiratory Pathology Summary

Asthma
= Reversible intermittent narrowing of conducting airways
Clinical features: SOB, wheeze, cough, hyperinflation

COPD
= chronic bronchitis + emphysema (obstructive) associated with cigarette smoking
Epidemiology: smokers
Clinical features:
- Productive cough
- Increasing breathlessness
- Frequent chest infections

Bronchiectasis
= permanent dilation of bronchi due to wall damage secondary to chronic necrotising infection
Clinical features:
- Productive cough, haemoptysis?
- Repeated infections

Idiopathic Pulmonary Fibrosis
= progressive patchy scarring of lower zones of both lungs
Epidemiology: old men
Clinical features:
- Insidious dry cough
- Progressive SOB
- Crackles

Pneumoconiosis
= lung damage secondary to particle inhalation: coal dust, silica, asbestos
Clinical features:
- Slowly increasing SOB
- Picked up on CXR

Sarcoid
= multisystem granulomatous disease involving lymph nodes and lungs
Epidemiology: African or northern european descent
Clinical features:
- Nodal enlargement
- Cough, SOB
- Fever, fatigue, weight loss, sweats

Hypersensitivity Pneumonitis
= inflammatory and fibrotic bronchiolar response to inhaled antigens
Clinical features:
- Cough, SOB

, - Fever, fatigue, weight loss, sweats
Lung cancer
Aetiology:
- Occupational
- Lung fibrosis
- Mutations: EGFR, KRAS, ALK, ROS1
Clinical Features:
- Haemoptysis
- Breathlessness
- Pain
- Hoarseness: recurrent laryngeal nerve
- Horner’s syndrome: sympathetic chain
- Dysphagia
- Weight loss, lethargy
- Hyponatraemia, hypokalaemia and hypercalcaemia in SCC

Pleuritis
Aetiology:
- Infection
- PE
- Emphysema
- Collagen vascular disease
Clinical features:
- Sharp chest pain
- Breathlessness
- Pleural rub

Pleural Effusion
Clinical features:
- No pleuritic chest pain
- Dry, non productive cough
- Dyspnea
- Orthopnea
- Dullness on percussion

Pneumothorax
Epidemiology: tall, thin, young male
Clinical features:
- Hyperresonance on percussion
- Tracheal deviation away from tension pneumothorax