Chest X-Ray Findings in RSV Infection in Children
Routine Chest Radiography is Not Recommended in Uncomplicated RSV Bronchiolitis
The American Academy of Pediatrics strongly recommends against routine chest radiography in children with bronchiolitis, reserving imaging only for severe cases requiring ICU admission or when airway complications like pneumothorax are suspected 1. This recommendation is based on evidence showing that chest X-rays do not correlate well with disease severity and lead to increased antibiotic use without improving outcomes 1.
Common Radiographic Findings When Imaging is Performed
When chest radiography is obtained in children with RSV infection, the most frequent findings include:
Primary Patterns (in order of frequency):
- Central pneumonia (32%) - characterized by perihilar infiltrates 2
- Normal chest X-ray (30%) - a substantial proportion show no radiographic abnormalities despite clinical bronchiolitis 2
- Peribronchitis (26%) - bronchial wall thickening and peribronchial infiltrates 2
Additional Findings:
- Hyperinflation/emphysema (11%) - air trapping from small airway obstruction 2
- Atelectasis - associated with increased risk of severe disease in some studies 1
- Lobar or segmental consolidation - can occur, particularly in RSV-infected children under 6 months of age 3
- Bronchopneumonia pattern - dispersed alveolar infiltrations, more common in virus-positive groups 3
- Pleural effusion (6%) - less common but can occur 2
- Pneumothorax - rare complication 2
Age-Related Considerations
There is no significant difference in radiographic findings between children under and over 6 months of age with RSV infection 2. However, lobar consolidations ("lobar pneumonia") appear more frequently in RSV-infected children under 6 months compared to older RSV-positive children 3. Interstitial pneumonia and peribronchitis often present together in children over 6 months of age 3.
Critical Clinical Pitfalls
Chest X-Ray Cannot Distinguish Viral from Bacterial Infection
Chest radiographs cannot reliably distinguish viral from bacterial pneumonia and do not reliably distinguish among various bacterial pathogens 1. The presence of consolidation on chest X-ray does not indicate bacterial superinfection, as this pattern occurs in pure RSV infection 3, 2.
Imaging Leads to Inappropriate Antibiotic Use
Children who undergo chest radiography are at 22.9-fold higher risk of receiving antibiotics (95% CI: 14.1-37.1), regardless of the radiographic findings 4. This represents unnecessary antibiotic exposure, as most RSV bronchiolitis is self-limited and does not require antibiotics 1.
Radiation Exposure Without Clinical Benefit
Chest X-rays in bronchiolitis patients result in longer hospital stays (10 vs. 8 days) without improving clinical outcomes 4. The American College of Radiology emphasizes that radiation exposure accumulates over a child's lifetime with potential increased malignancy risk 5.
When Chest Radiography IS Indicated
Obtain chest X-ray in RSV-infected children only when:
- Respiratory effort is severe enough to warrant ICU admission 1
- Signs of airway complications such as pneumothorax are present 1
- Unexpected clinical deterioration occurs 5
- Underlying cardiac or pulmonary disorder is present 5
- Considering intubation 5
Practical Implementation
The percentage of chest X-rays performed in bronchiolitis has appropriately decreased from 78% in 2010 to 33% in 2017 in some centers, with optimal rates as low as 11% 4. Clinicians should resist ordering chest radiography based solely on clinical diagnosis of bronchiolitis, as it adds cost (approximately €381 per patient) and radiation exposure without influencing management in most cases 4.