Who is recommended to have a chest X-ray, particularly those with a history of respiratory issues, such as chronic obstructive pulmonary disease (COPD) or pneumonia, cancer, or immunocompromised status, including older adults and those with a history of smoking or exposure to respiratory toxins?

Who Should Have a Chest X-Ray

Chest radiography is usually appropriate for patients with acute respiratory illness who have positive physical examination findings, abnormal vital signs, or risk factors such as older age, smoking history, immunocompromised status, or comorbidities like heart disease. 1

Initial Evaluation of Suspected COPD

Chest X-ray should be obtained during the initial diagnostic evaluation of patients with suspected COPD to exclude alternative diagnoses (lung cancer, heart failure, interstitial lung disease) and identify concomitant respiratory diseases, though it is frequently normal in early disease. 1

• The European Respiratory Society and American Thoracic Society recommend chest radiography primarily to exclude other conditions rather than as a primary diagnostic tool for COPD itself. 1, 2
• Chest X-ray is not performed during routine follow-up of stable COPD patients. 1
• For smokers aged 40 or over receiving bronchodilators, chest X-ray at initial COPD assessment detects potentially treatable pathology in 14% of cases and identifies lung cancer in approximately 2% of patients. 3

Acute Respiratory Illness Presentations

Patients Requiring Chest X-Ray

Chest radiography is usually appropriate for:

• Acute respiratory illness with positive physical examination findings (diminished breath sounds, crackles, egophony, dullness to percussion). 1
• Abnormal vital signs (fever, tachypnea, tachycardia, hypoxia). 1
• Risk factors present: organic brain disease, immunocompromised status, older age, nursing home residence. 1
• Complicated COPD exacerbation with chest pain, fever, leukocytosis, or history of coronary artery disease or heart failure. 1
• Complicated asthma exacerbation with suspected pneumonia or pneumothorax. 1

Patients Where Chest X-Ray May Not Be Needed

• Uncomplicated acute asthma exacerbation without suspicion of pneumonia or pneumothorax (imaging usually not appropriate, though chest X-ray may be appropriate). 1
• Uncomplicated COPD exacerbation without chest pain, fever, leukocytosis, or cardiac comorbidities (chest X-ray is usually appropriate but has low yield). 1
• Acute cough illness in low-risk patients: For adults with acute cough and negative physical examination, normal vital signs, and no risk factors, the yield of chest radiography is very low (approximately 2% have infiltrates), and routine imaging does not improve clinical outcomes. 1

Chronic Dyspnea Evaluation

Chest radiography is usually appropriate as the first-line imaging modality for patients with chronic dyspnea of noncardiovascular origin. 1

• If chest X-ray is normal or equivocal and clinical suspicion remains high, chest CT without contrast is either usually appropriate or may be appropriate as second-line imaging. 1
• For chronic cough patients with normal chest X-rays, routine chest CT has low diagnostic yield for major pathology (<1% for malignancy or infectious disease), despite finding abnormalities in 37% of cases. 4

Suspected Lung Cancer

For patients with risk factors for lung cancer (smoking history, age, persistent or changing cough), chest radiography should be obtained. 1

• Bronchoscopy is indicated even with normal chest X-ray in smokers with hemoptysis and persistent cough after antimicrobial treatment. 1
• Chest X-ray has positive predictive value of only 36-38% for airway cancers, with bronchoscopy having higher yield (50-89%). 1

Chronic Dyspnea of Noncardiovascular Origin

Chest radiography is the appropriate first-line imaging modality for evaluating chronic dyspnea when cardiovascular causes have been excluded. 1

• Chest CT without contrast may be appropriate for conditions of unclear etiology, suspected COPD, small airways disease, or post-COVID-19 complications. 1

Key Clinical Pitfalls to Avoid

• Do not assume normal chest X-ray excludes significant pathology: Chest radiography has only 69-75% sensitivity for pneumonia, misses approximately 50% of pneumothoraces, and is frequently normal in early COPD. 1, 5
• Radiation exposure considerations: In chronic cough patients with normal chest X-rays and low clinical suspicion, routine CT scanning may not be warranted given radiation harm and low diagnostic yield. 4
• Clinical judgment supersedes imaging: History and physical examination suggesting need for antibiotic treatment should guide the decision to obtain chest radiography, particularly in acute cough illness where routine imaging has minimal benefit. 1