What is the initial management approach for a patient presenting with a chronic cough?

Initial Management of Chronic Cough

Begin with a focused history and physical examination, obtain a chest radiograph, and immediately discontinue ACE inhibitors if present, then initiate sequential empiric treatment targeting the three most common causes: upper airway cough syndrome (UACS), asthma, and gastroesophageal reflux disease (GERD). 1, 2

Step 1: Initial Assessment and Risk Factor Modification

Critical History Elements

• Determine if the patient is taking an ACE inhibitor - if yes, discontinue immediately and replace with an alternative antihypertensive, as cough typically resolves within days to 2 weeks (median 26 days) 1, 3, 4
• Assess smoking status - counsel and assist with smoking cessation, as 90% of patients with chronic bronchitis will have cough resolution after quitting 1, 3
• Screen for red flags requiring urgent evaluation: hemoptysis, age >45 years with new or changed cough pattern, prominent dyspnea, hoarseness, systemic symptoms, trouble swallowing, vomiting, or recurrent pneumonia 2

Initial Diagnostic Testing

• Obtain chest radiography as the first-line imaging test, which achieves diagnosis in 82-93% of cases when used in standardized protocols 2, 4
• Avoid routine chest CT initially, as wide application shows low clinical yield; reserve HRCT for patients with abnormal chest radiographs or failed empiric treatment 2

Step 2: Sequential Empiric Treatment Algorithm

First-Line: Treat Upper Airway Cough Syndrome (UACS)

• Initiate a first-generation antihistamine/decongestant combination (e.g., brompheniramine with sustained-release pseudoephedrine) 1, 3, 4
• Critical pitfall: Newer non-sedating antihistamines are ineffective for UACS; only first-generation agents work 3
• Expected response: Initial improvement within 1-2 weeks, though complete resolution may take several weeks 3

Second-Line: Add Asthma Treatment if Incomplete Response After 2-4 Weeks

• Start inhaled corticosteroids combined with long-acting β-agonists (e.g., fluticasone/salmeterol twice daily) 3, 4
• Continue the UACS treatment as multiple causes frequently coexist 1, 3
• Expected response: Monitor for improvement within 2-4 weeks 3
• Consider bronchoprovocation challenge or induced sputum eosinophil testing if diagnosis uncertain 3

Third-Line: Add GERD Treatment if Still Inadequate Response

• Initiate proton pump inhibitor therapy with dietary modifications 3, 4
• Maintain all previous treatments that showed partial benefit, as cough is often multifactorial 1, 3
• Expected response: Assessment over 1-3 months, as GERD-related cough responds slowly 3

Step 3: Key Principles of Treatment

Sequential and Additive Therapy

• Use sequential and additive steps because more than one cause is present in the majority of chronic cough cases 1
• Do not discontinue partially effective treatments when adding the next therapeutic trial 3
• Adequate treatment duration is crucial - both in terms of agents used and duration of treatment 1

Common Pitfalls to Avoid

• Do not rely on cough characteristics for diagnosis, as timing and quality have little diagnostic value 1
• Do not perform extensive testing before empiric trials unless red flags are present 2, 5
• Do not use second-generation antihistamines for UACS, as they lack efficacy 3

Step 4: When Initial Management Fails

After 4-6 Weeks of Sequential Treatment

• Consider additional diagnostic testing: 24-hour esophageal pH monitoring, upper GI endoscopy, or barium swallow for refractory GERD 1
• Add prokinetic agents (e.g., metoclopramide) with rigorous dietary adherence for GERD 1
• Obtain HRCT scan to evaluate for bronchiectasis or occult interstitial disease 1, 2

Advanced Evaluation

• Perform bronchoscopy to look for occult airway disease (endobronchial tumor, sarcoidosis, suppurative infection, eosinophilic or lymphocytic bronchitis) 1
• Consider uncommon causes: nonacid reflux disease, swallowing disorders, congestive heart failure, or habit cough based on clinical findings 1
• Refer to a cough specialist before labeling as unexplained/idiopathic cough 1