What is the recommended treatment for a patient with persistent cough, slightly hyperinflated lungs, prominent lung markings, mild peribronchial thickening, and mild cardiomegaly?

Management of Persistent Cough with Radiographic Findings of Hyperinflation and Peribronchial Thickening

Perform spirometry immediately to assess for chronic obstructive pulmonary disease (COPD) or asthma, then initiate empirical treatment targeting the three most common causes: upper airway cough syndrome, cough-variant asthma, and gastroesophageal reflux disease, while addressing the mild cardiomegaly separately. 1

Initial Diagnostic Workup

The chest radiograph has already been obtained and shows hyperinflation with peribronchial thickening—findings that suggest chronic airways disease but require spirometry for definitive characterization. 1

• Spirometry with bronchodilator response is mandatory to differentiate between COPD, asthma, or other obstructive patterns, measuring FEV1 before and after inhaling salbutamol 400 mcg by metered-dose inhaler and spacer or 2.5 mg by nebulizer. 1
• The hyperinflated lungs and peribronchial thickening on chest X-ray suggest either COPD or asthma, but 46% of patients with persistent cough have one of these diagnoses in primary care. 1
• Assess smoking status immediately, as cigarette smoking is dose-related to chronic cough and smoking cessation resolves cough in the majority within 4 weeks. 1, 2
• Review all medications for ACE inhibitor use, which must be discontinued regardless of temporal relationship to cough onset, with resolution typically occurring within days to 2 weeks (median 26 days). 1, 3, 2

Empirical Treatment Algorithm

Since the chest radiograph shows abnormalities (hyperinflation and peribronchial thickening), proceed with targeted treatment rather than a generic chronic cough algorithm. 1

For Suspected COPD (if spirometry confirms obstruction):

• Initiate combination bronchodilator therapy with ipratropium and albuterol by metered-dose inhaler four times daily, as this combination is 21-46% more effective than either agent alone in COPD patients. 4
• Albuterol 400 mcg by metered-dose inhaler provides superior bronchodilation compared to oral aminophylline or terbutaline, with fewer side effects. 5

For Suspected Cough-Variant Asthma (if spirometry is normal or shows reversibility):

• Offer a therapeutic trial of prednisolone for patients with normal spirometry in whom cough-variant asthma or eosinophilic bronchitis is suspected, as many patients lack sufficient spirometric reversibility to meet traditional asthma criteria. 1, 3, 2
• A 2-week oral steroid trial effectively excludes eosinophilic airway inflammation if there is no response. 1
• Inhaled corticosteroids with or without bronchodilators should be initiated even without spirometric evidence of obstruction if asthma is suspected. 2

For Upper Airway Cough Syndrome:

• Initiate intranasal corticosteroids and antihistamines if rhinosinusitis symptoms are present, as upper airway disease is the most common cause of chronic cough in immunocompetent nonsmokers. 1, 3, 2

For Gastroesophageal Reflux Disease:

• Intensive acid suppression with proton pump inhibitors and alginates for a minimum of 3 months is required, as GERD is frequently overlooked and may occur without gastrointestinal symptoms. 1, 3, 2
• Treatment duration of at least 8-12 weeks is necessary before concluding GERD is not contributing. 3, 2

Addressing the Mild Cardiomegaly

• Evaluate the cardiomegaly separately with echocardiography and BNP/NT-proBNP, as heart failure can cause cough through pulmonary congestion, though this is less common than the primary respiratory causes. 1
• Optimize heart failure management if present, as this may independently contribute to cough symptoms.

Common Pitfalls to Avoid

• Do not rely on single peak expiratory flow measurements instead of FEV1, as PEF is less accurate in diagnosing airflow obstruction as a cause of cough. 1
• Do not proceed to CT imaging prematurely—reserve high-resolution CT only after sequential empiric treatment for all three common causes has failed and adequate treatment duration has been allowed (several weeks for upper airway/asthma, ≥3 months for GERD). 1, 2
• Do not diagnose "idiopathic cough" until specialist evaluation with comprehensive protocols has been completed. 1, 2
• Do not overlook extrapulmonary causes, particularly GERD, which is the most common reason for treatment failure in general respiratory clinics. 1, 2

Red Flags Requiring Direct Investigation

Pursue immediate investigation rather than empirical treatment if any of the following are present: 1, 2

• Hemoptysis (even small volume or streaks)
• Significant dyspnea disproportionate to radiographic findings
• Fever or systemic symptoms
• Unintentional weight loss
• History of cancer, tuberculosis, or AIDS
• New onset cough or change in chronic cough characteristics in a smoker

Bronchoscopy is indicated even with normal chest radiograph if the patient is a smoker with both persistent cough and hemoptysis. 1

When to Refer to Specialist

Refer to a specialist cough clinic when empirical treatments have failed after adequate trials (minimum 2 weeks for steroids, 3 months for GERD therapy), diagnostic uncertainty persists, or suspicion of uncommon causes exists. 1, 3, 2