Asthma ⭐

• Symptoms: worsen at night; episodic wheezing; can present without wheeze or dyspnoea, but with cough – typically a dry cough, worst in the early morning (when bronchioles are most reactive), exacerbate by cold or exercise
• Recent beta-blocker or NSAID use may precipitate asthma
• Dxg: methacholine inhalation challenge / trial of inhaled bronchodilators or corticosteroid

Tuberculosis 🚩

• constitutional symptoms (fever, night sweats, weight loss), sputum production, hemoptysis, travel hx, contact hx, and immunosuppression (e.g. steroids) which may predispose to opportunistic or atypical infection
• Examine for upper lobe fibrosis or collapse (dullness, tracheal deviation etc)

Non-asthmatic Eosinophilic Chronic Bronchitis ⭐

• Presentation: normal airway hyperresponsiveness, sputum eosinophilia + metachromatic cells (rule out if less than 3%), no arflow obstruction

Post-Infectious

• Symptoms: recent flu-like symptoms with significant cough (RTI)
• Persist for 1-3 months

Interstitial Lung Disease

• progressive dyspnoea
• history or current features (e.g. joint pain, rash) of rheumatological diseases like RA, scleroderma, ankylosing spondylitis, and lupus

Cancer

• Presentation: recent change in chronic ‘smoker’s cough’, or constitutional symptoms (any weight loss or loss of appetite), progressive dyspnoea

Upper Airway Cough Syndrome (UACS) ⭐ ⭐ - Nasal and Throat Symptoms

• Chronic Rhinitis + Post Nasal Drip -> upper airway secretions may trigger the cough reflex
• Cough is triggered immediately upon lying down, and the patient may even feel a sensation of liquid dripping into the back of the throat
• Examination of the nose may reveal excess secretions, inflammed nasal mucosae, or nasal polyps.
• Normal Chext X-ray
• Responsive to decongestant and first generation histamine H1 receptor antagonist (not cause by sinusitis)

Gastro-esophageal Reflux Disease (GERD) ⭐ -> irritating the lower respiratory tract through aspiration thus stimulating esophageal-bronchial cough reflex

• Heartburn or GI symptoms
• Symptoms: Worsen at night

ACE-Inhibitor ⭐ : due to inhibition of bradykinin metabolism

• 5-30% of patients who starting new med
• Substitute ACE-I with angiotensin receptor blocker

Chronic Obstructive Pulmonary Disease

• Presentation: chronic smoker; cough and progressive exertional dyspnea
• Examine for wheeze
• spirometry and be staged according to the GOLD classifications