Top 15 Differential Diagnoses

TIER 1 — Most Common (>60% of chronic cough cases account for the top 3)

1. 🔵 Gastro-oesophageal Reflux Disease / Laryngopharyngeal Reflux (GERD/LPR)

• Typical: heartburn, regurgitation, chronic cough, throat clearing, hoarseness worse in the morning
• Atypical: no heartburn in up to 50% (silent reflux); pure LPR often presents with hoarseness and cough as the only symptoms
• Wheeze mechanism: reflux-triggered bronchospasm via vagal reflex or micro-aspiration
• Key features in a 48F: perimenopause reduces lower oesophageal sphincter tone; oestrogen fluctuation exacerbates LPR
• Sources: Sleisenger & Fordtran's GI and Liver Disease; Cummings Otolaryngology; Murray & Nadel's Respiratory Medicine

2. 🔵 Asthma (Classic / Cough-Variant / Occupational)

• Typical: episodic wheeze, breathlessness, chest tightness, nocturnal cough
• Atypical (Cough-Variant): cough as the sole manifestation; wheeze may be absent at rest
• Hoarseness: from vocal cord strain, inhaled steroid use, or associated LPR
• Worsening pattern supports this; FEV1 reversibility or positive bronchoprovocation test confirms
• Source: Murray & Nadel's Respiratory Medicine; Textbook of Family Medicine 9e

3. 🔵 Upper Airway Cough Syndrome (UACS) / Chronic Rhinosinusitis with Postnasal Drip

• Typical: constant throat-clearing, sensation of secretions, nasal congestion, "cobblestoning" of posterior pharynx
• Hoarseness from mucosal irritation; wheeze from extrathoracic variable upper airway obstruction
• Together with asthma and GERD, accounts for >90% of chronic nonproductive cough cases
• Source: Murray & Nadel's Respiratory Medicine, p. 873

TIER 2 — Serious / Must-Not-Miss

4. 🔴 Lung Cancer (Bronchogenic Carcinoma)

• Hoarseness = recurrent laryngeal nerve (RLN) invasion/compression — a classic red flag
• Typical: smoker, progressive cough, haemoptysis, weight loss, dyspnoea
• Atypical: non-smoker (adenocarcinoma most common in women), no haemoptysis; wheeze from central airway obstruction
• Pancoast tumour → Horner's syndrome + brachial plexopathy
• Superior vena cava syndrome → facial/neck swelling + hoarseness + cough
• Sources: Robbins Pathologic Basis of Disease; Washington Manual; Harrison's 22e; Schwartz Surgery 11e

5. 🔴 Laryngeal / Hypopharyngeal Cancer

• Classic presentation: progressive hoarseness + cough + dysphagia ± haemoptysis; risk factors: smoking, alcohol, HPV (women increasingly affected)
• Wheeze/stridor develops as intrinsic laryngeal obstruction progresses
• Key point: hoarseness lasting >3 weeks in a smoker = urgent laryngoscopy
• Source: Cummings Otolaryngology

6. 🔴 Thyroid Goitre / Substernal Thyroid / Thyroid Cancer with Tracheal Compression

• Large goitre compresses trachea → fixed wheeze/stridor, cough
• RLN involvement → hoarseness (especially thyroid cancer or Riedel's thyroiditis)
• Breathlessness worsens in supine position (orthopnoea)
• Harrison's 22e notes: patients may complain of a cough or wheezing from airway compression, hoarseness from RLN, and dysphagia from oesophageal compression
• Source: Harrison's Principles of Internal Medicine 22e

7. 🔴 Oesophageal Cancer

• Progressive dysphagia + weight loss; hoarseness from RLN invasion + cough (from tracheo-oesophageal fistula)
• Wheeze and breathlessness from direct extension into tracheobronchial tree
• Source: Yamada's Textbook of Gastroenterology; Harrison's 22e

8. 🔴 Mediastinal Mass (Lymphoma, Thymoma, Sarcoidosis, Metastatic Nodes)

• Compresses trachea/mainstem bronchi → wheeze + breathlessness; compresses RLN → hoarseness; compresses SVC → SVCS
• Women age 40–60: lymphoma (Hodgkin's/NHL), anterior mediastinal masses
• Source: Harrison's 22e — Superior Vena Cava Syndrome section

TIER 3 — Important, Less Immediately Life-Threatening

9. 🟡 Vocal Cord Dysfunction (VCD) / Inducible Laryngeal Obstruction (ILO)

• Paradoxical adduction of vocal cords during inspiration → stridor mimicking wheeze
• More common in women (3:1), particularly those with anxiety, GERD, or post-URI
• Key differentiator: stridor loudest over neck (not chest), inspiratory > expiratory, no response to bronchodilators
• Spirometry: flattening of inspiratory loop; confirmed by laryngoscopy during episode
• Often misdiagnosed as refractory asthma for years

10. 🟡 ACE Inhibitor-Induced Cough

• Affects ~15% of users; far more common in women than men
• Typical: dry, persistent, tickling cough beginning weeks after starting (e.g., ramipril, lisinopril, perindopril)
• Can trigger bronchospasm and worsen asthma; hoarseness from laryngeal irritation
• Diagnostic test: cessation of ACE inhibitor (cough resolves within 1–4 weeks)

11. 🟡 COPD / Chronic Bronchitis / Emphysema

• Progressive exertional breathlessness, productive cough, wheeze; smoker or significant passive exposure
• Hoarseness less prominent unless superimposed laryngeal pathology or RLN compression from mediastinal bullae/enlarged nodes
• Spirometry: post-bronchodilator FEV1/FVC <0.70 confirms
• Source: Miller's Anesthesia; Textbook of Family Medicine

12. 🟡 Bronchiectasis

• Chronic productive cough (purulent), wheeze, dyspnoea; recurrent chest infections
• May follow childhood pertussis, TB, or recurrent pneumonias
• Hoarseness: less typical but can occur with associated sinonasal disease
• HRCT chest is diagnostic (signet ring sign, dilated airways)
• Source: Murray & Nadel's Respiratory Medicine

13. 🟡 Cardiac Failure (Left-Sided) — Cardiac Asthma

• Pulmonary venous congestion → cardiac wheeze + breathlessness (cardiac asthma); nocturnal paroxysmal dyspnoea
• Cough may be dry or frothy; hoarseness can occur from enlarged pulmonary arteries or left atrial enlargement compressing RLN (Ortner's syndrome)
• Key features: orthopnoea, bilateral basal crackles, raised JVP, S3/S4, BNP elevated
• Source: Miller's Anesthesia; Textbook of Family Medicine

14. 🟡 Pertussis (Whooping Cough) — Subacute/Chronic Phase

• Underdiagnosed in adults. Classic paroxysmal cough with inspiratory whoop, post-tussive vomiting
• Can persist 8–12 weeks; hoarseness from laryngeal strain during coughing paroxysms
• Waning vaccine immunity in adults; often missed because whoop may be absent
• Source: Murray & Nadel's Respiratory Medicine

15. 🟡 Pulmonary Sarcoidosis / Hypersensitivity Pneumonitis

• Bilateral hilar lymphadenopathy can compress airways → cough, wheeze, hoarseness (via RLN or tracheal compression)
• Breathlessness from restrictive or obstructive pattern; cough often dry
• Hypersensitivity pneumonitis: occupational/environmental antigen exposure; restrictive pattern on PFTs
• Source: Goldman-Cecil Medicine

Summary Table

Key Investigations to Prioritise

1. Chest X-ray (all patients — screen for mass, hilar adenopathy, cardiomegaly, consolidation)
2. Spirometry with bronchodilator reversibility (asthma vs. COPD)
3. CT chest with contrast (if any red flag — mass, RLN palsy, mediastinal abnormality)
4. Direct laryngoscopy (hoarseness >3 weeks — exclude laryngeal pathology)
5. Neck ultrasound / thyroid function (thyroid mass)
6. 24-hour pH-impedance study or empiric PPI trial (GERD/LPR)
7. Drug history review (ACE inhibitors)
8. Spirometry inspiratory flow-volume loop (VCD/central airway obstruction)

⚠️ Clinical priority: In a 48-year-old woman, the combination of progressive hoarseness + worsening cough + wheeze must prompt urgent exclusion of a compressive or infiltrative process (lung cancer, laryngeal cancer, mediastinal mass, thyroid pathology) before attributing symptoms to benign causes like asthma or GERD. — Harrison's Principles of Internal Medicine 22e; Robbins Pathologic Basis of Disease; Murray & Nadel's Respiratory Medicine

Additional Differentials — #16 to #24

16. 🟡 Idiopathic Pulmonary Fibrosis (IPF) / Interstitial Lung Disease (ILD)

• Typical: dry, persistent, non-productive cough; progressive exertional breathlessness; bilateral fine Velcro crackles at lung bases
• Atypical: wheeze can occur in fibrotic airways; hoarseness is uncommon but arises if secondary pulmonary hypertension compresses the RLN, or from associated connective tissue disease affecting the larynx
• Relevant in a 48F: ILD associated with connective tissue diseases (rheumatoid arthritis, Sjögren's, systemic sclerosis) disproportionately affects women
• HRCT: honeycombing, traction bronchiectasis, subpleural reticulation
• Sources: Goldman-Cecil Medicine; Tintinalli's Emergency Medicine; Fishman's Pulmonary Diseases

17. 🔴 Aortic Aneurysm / Cardiovascular Compression of the RLN (Ortner's / Cardio-Vocal Syndrome)

• Compression of the left recurrent laryngeal nerve by an enlarged aortic arch, aortic aneurysm, or markedly enlarged left atrium → hoarseness + cough
• Breathlessness and wheeze from large vessel compression of the left mainstem bronchus or trachea
• In a 48F: hypertensive cardiovascular disease, mitral stenosis causing left atrial enlargement (Ortner's syndrome classically), or atherosclerotic aortic aneurysm
• Key clue: hoarseness + cardiovascular signs with no laryngeal pathology on laryngoscopy
• Source: Adams & Victor's Neurology — Diseases Affecting the Vagus; Harrison's 22e

18. 🟡 Tracheomalacia / Tracheal Stenosis

• Post-intubation tracheal stenosis (history of prolonged ventilation) or dynamic tracheomalacia (airway collapse on expiration)
• Presents as: fixed or variable wheeze (monophonic), progressive breathlessness, barking cough, hoarseness
• "All that wheezes is not asthma" — failure to respond to bronchodilators is a key differentiator
• Diagnosis: flow-volume loop (biphasic flattening for fixed obstruction; variable pattern for dynamic), bronchoscopy
• Source: Cummings Otolaryngology; Miller's Anesthesia

19. 🟡 Foreign Body Aspiration (Subacute / Chronic)

• Underrecognised in adults; a partially obstructing object produces chronic cough, unilateral wheeze, hoarseness (if lodged at or above the glottis)
• Adults may aspirate small bones, dental fragments, or medication tablets
• Classic clue: sudden choking episode that was forgotten or trivialised; wheeze that doesn't improve with inhalers; unilateral hyperinflation on CXR
• Rigid bronchoscopy is diagnostic and therapeutic
• Source: Cummings Otolaryngology — Aerodigestive Foreign Bodies

20. 🟡 Non-Asthmatic Eosinophilic Bronchitis (NAEB)

• Eosinophilic airway inflammation without bronchial hyperresponsiveness — presents identically to cough-variant asthma but spirometry and bronchoprovocation tests are normal
• Symptoms: dry chronic cough ± mild wheeze; breathlessness less prominent
• Hoarseness from associated eosinophilic laryngitis is recognised
• Diagnosis: induced sputum with eosinophilia >3%; responds to inhaled corticosteroids
• Key reason asthma therapy may fail to resolve cough fully

21. 🟡 Pulmonary Tuberculosis (TB)

• In a 48F with progressive worsening, TB must not be missed, especially in those with immigration background, travel history, immunosuppression, or prior TB contact
• Typical: chronic productive cough, haemoptysis, night sweats, weight loss, fever
• Hoarseness (laryngeal TB): haematogenous or direct spread to larynx — now rare but classic; hoarseness + cough in TB = laryngeal involvement until proven otherwise
• Wheeze from endobronchial involvement or mediastinal lymphadenopathy compressing airways
• Source: Textbook of Family Medicine; Rosen's Emergency Medicine

22. 🟡 Pulmonary Arterial Hypertension (PAH)

• Primary or secondary PAH (from connective tissue disease, chronic thromboembolic disease, HIV, appetite suppressants)
• More common in women aged 30–60 (female:male 2:1)
• Symptoms: progressive exertional breathlessness, near-syncope, fatigue; cough (from pulmonary artery dilation compressing airways); wheeze from peribronchial oedema
• Hoarseness via compression of left RLN by a dilated pulmonary artery (analogous to Ortner's)
• ECG: right axis deviation, right ventricular strain; echo confirms

23. 🟡 Connective Tissue Disease — Sjögren's Syndrome / Systemic Sclerosis (Scleroderma)

• Sjögren's: xerotrachea (dry airways) → persistent dry cough + hoarseness from sicca involvement of laryngeal mucosa; can cause follicular bronchiolitis, lymphocytic interstitial pneumonia
• Systemic sclerosis: oesophageal dysmotility → severe LPR causing hoarseness and cough; pulmonary fibrosis causing breathlessness; telangiectasias of vocal cords
• Relevant in a 48F: both peak in perimenopausal women
• ANA, anti-Ro/La (Sjögren's), anti-Scl-70/anti-centromere (scleroderma)

24. 🟠 Chronic Cough Hypersensitivity Syndrome (Neurogenic / Refractory Chronic Cough)

• Emerging diagnostic entity: heightened sensitisation of cough afferents (vagal C-fibres), often triggered by UACS, GERD, or viral illness but persisting beyond resolution of the trigger
• More common in perimenopausal women — oestrogen modulates cough receptor sensitivity
• Symptoms: tickle/itch sensation in throat triggering uncontrollable coughing paroxysms; allotussia (cough triggered by talking, cold air, perfumes)
• Associated hoarseness from vocal strain; wheeze from forced expiratory flow during cough episodes
• Responds poorly to standard therapies; low-dose neuromodulators (gabapentin, pregabalin, amitriptyline) or speech therapy are used

Updated Complete Summary Table (#16–24)

Clinical note on the full 24: In this 48-year-old perimenopausal woman, diagnoses #22 (PAH), #23 (Sjögren's/scleroderma), and #24 (neurogenic cough) deserve particular attention as they cluster in this precise demographic and are frequently delayed in diagnosis. Diagnoses #17 (cardiovascular RLN compression) and #21 (TB) are must-not-miss conditions that require active exclusion.

Sources: Adams & Victor's Neurology 12e; Goldman-Cecil Medicine; Cummings Otolaryngology; Fishman's Pulmonary Diseases; Miller's Anesthesia