What is the next step in managing a patient with a chronic cough and a history of multiple cervical spine discectomies and fusions, who has a normal chest X-ray (CXR) with no signs of pneumonia?

Management of Chronic Cough with Normal Chest X-Ray

For a patient with chronic cough and normal chest X-ray, proceed with empiric treatment for the most common causes (upper airway cough syndrome, asthma, gastroesophageal reflux disease) and reserve CT chest for cases where symptoms persist despite 4-8 weeks of appropriate empiric therapy or when specific clinical features suggest underlying structural lung disease. 1

Initial Management Strategy

Do Not Routinely Order CT Imaging Initially

• Chest CT should be selective rather than routine in patients with normal chest radiographs and chronic cough. 1, 2
• Studies demonstrate that 74 out of 81 patients with chronic cough were successfully managed clinically without CT examination, suggesting CT would not have changed management in the majority. 1
• The CHEST guidelines explicitly recommend against routine antibiotics when there is no clinical or radiographic evidence of pneumonia. 1

Empiric Treatment Approach

• Begin empiric treatment targeting the three most common causes of chronic cough: upper airway cough syndrome (postnasal drip), asthma/cough-variant asthma, and gastroesophageal reflux disease. 1, 2
• Treat each condition sequentially or in combination for 4-8 weeks before declaring treatment failure. 1, 2
• The American College of Radiology recommends evaluation and treatment for gastroesophageal reflux disease in adults with chronic cough. 2

When to Escalate to CT Imaging

Clear Indications for High-Resolution CT Chest

• Persistent cough despite 4-8 weeks of appropriate empiric treatment of common causes. 1, 2
• Smoking history with chronic cough, even with normal chest X-ray - central airway tumors can be bronchoscopically visible but radiographically occult in 16% of cases. 1, 3
• Any hemoptysis in a smoker - bronchoscopy is indicated even when chest radiograph is normal. 1, 3
• Clinical examination findings suggesting structural lung disease (crackles, diminished breath sounds, hypoxemia). 2
• Abnormal pulmonary function tests suggesting restrictive or obstructive disease. 2

Diagnostic Yield of CT When Appropriately Selected

• Chest CT reveals clinically relevant abnormalities in approximately 36% of patients with chronic cough and normal chest X-ray. 4
• The negative predictive value of chest X-ray for pulmonary causes of chronic cough is only 64%, meaning chest X-ray misses significant pathology in more than one-third of cases. 4
• Most common findings on CT include bronchiectasis (11.9%), bronchial wall thickening (10.2%), and mediastinal lymphadenopathy (8.5%). 4

Risk Stratification for Malignancy

High-Risk Features Requiring Bronchoscopy

• Smoking history plus chronic cough warrants bronchoscopy even with normal chest X-ray. 1
• Any hemoptysis in a smoker requires bronchoscopy regardless of imaging findings. 1, 3
• Studies show that 13 of 81 patients (16%) with completely obstructing central airway cancers had normal chest radiographs but all had risk factors and symptoms suggestive of bronchogenic carcinoma. 1

Moderate-Risk Features

• Age >70 years with new or changing cough character - up to 20% may have incidental bronchiectasis on imaging. 2
• Chronic cough lasting >8 weeks without response to empiric therapy. 1, 2
• Studies document that 1-2% of patients with chronic cough have underlying malignancy. 2

Special Considerations for This Patient

Cervical Spine Surgery History

• The patient's history of multiple cervical discectomies and fusions is noted on imaging but is not relevant to the chronic cough evaluation. 5
• Postoperative dysphagia occurs in 9.5% of ACDF patients and could theoretically contribute to aspiration, but this typically presents acutely postoperatively, not as isolated chronic cough. 5

Age-Related Imaging Findings

• Elderly patients (>65-70 years) frequently show CT abnormalities including parenchymal bands, ground glass opacities, bronchiectasis, and bronchial wall thickening even without respiratory symptoms. 2
• Up to 20% of subjects >70 years have bronchiectasis on imaging, with 57% being asymptomatic. 2
• Do not assume radiographic findings of chronic changes are necessarily the cause of current cough symptoms in elderly patients. 2

Critical Pitfalls to Avoid

Overuse of Imaging

• Do not rush to CT imaging before addressing common and treatable causes of chronic cough with empiric therapy. 1, 2
• Chest CT was noncontributory or normal in 48 of 49 postdeployment military personnel with respiratory complaints in the STAMPEDE study, highlighting low yield when applied indiscriminately. 1

Underuse of Imaging in High-Risk Patients

• Do not rely solely on chest X-ray in smokers with chronic cough - proceed to CT and consider bronchoscopy given high pretest probability for malignancy. 1, 3
• Do not dismiss the need for further workup in patients whose cough persists despite appropriate empiric treatment. 1, 2

Misinterpretation of Normal Imaging

• Ultra-early stage infections may present with clinical symptoms before radiographic abnormalities become apparent. 6
• The absence of CT findings does not exclude infection, particularly in acute bronchitis or early viral pneumonia. 6

Practical Algorithm

1. Confirm chronic cough duration (>8 weeks in adults). 1, 2
2. Assess for red flags: smoking history, hemoptysis, constitutional symptoms, abnormal vital signs. 1
3. If red flags present: Proceed directly to CT chest and consider bronchoscopy. 1, 3
4. If no red flags: Initiate empiric treatment for upper airway cough syndrome, asthma, and gastroesophageal reflux disease. 1, 2
5. Reassess at 4-8 weeks: If no improvement, order high-resolution CT chest without contrast. 1, 2
6. If CT reveals abnormalities: Treat accordingly (bronchiectasis, interstitial lung disease, etc.). 1, 4
7. If CT normal and symptoms persist: Consider bronchoscopy to evaluate for endobronchial lesions or other airway pathology. 1, 2