Table 3 Main differential diagnoses of COPD

COPD

• Onset in mid-life and later

• Symptoms slowly progressive

• History of smoking or exposure to other types of pollution

Asthma

• Onset usually early in life

• Symptoms vary widely from day to day

• Symptoms worse at night/early morning

• Allergy, rhinitis and/or eczema also present

• Family history of asthma

• Obesity can co-exist

Congestive heart failure

• Chest X-ray shows dilated heart

• Older patients

• Symptoms slowly progressive

• Pulmonary oedema or ankle swelling

• Night-time symptoms (orthopnoea)

• Pulmonary function tests indicate volume restriction, not airflow limitation

Bronchiectasis

• No or sparse smoking history

• Large volumes of purulent sputum

• Frequent exacerbations

• Possible co-existence of auto-immune disease

• Commonly associated with bacterial infection

• Chest X-ray shows bronchial dilation/wall thickening