On chest imaging, how do bronchiolitis and pneumonia typically differ?

On chest imaging, how do bronchiolitis and pneumonia typically differ?

• A. Bronchiolitis shows hyperinflation and peribronchial thickening; pneumonia shows focal consolidation
• B. Bronchiolitis shows focal consolidation; pneumonia shows hyperinflation
• C. Bronchiolitis shows pleural effusion; pneumonia shows enlarged heart
• D. Bronchiolitis shows lobar atrophy; pneumonia shows interstitial markings

Answer: (A)

Bronchiolitis and pneumonia differ in the level of lung involvement and the resulting imaging patterns. Bronchiolitis is inflammation of the small airways, which causes air trapping. On chest radiographs this appears as hyperinflated lungs with flattened diaphragms and thickened airway walls (peribronchial thickening). Pneumonia, on the other hand, involves filling of the alveolar spaces with inflammatory material, producing a focal area of increased density—consolidation—often in a single lobe or segment, and sometimes with air bronchograms. So the combination of hyperinflation and peribronchial thickening points to bronchiolitis, whereas focal consolidation points to pneumonia.

Bronchiolitis and pneumonia differ in the level of lung involvement and the resulting imaging patterns. Bronchiolitis is inflammation of the small airways, which causes air trapping. On chest radiographs this appears as hyperinflated lungs with flattened diaphragms and thickened airway walls (peribronchial thickening). Pneumonia, on the other hand, involves filling of the alveolar spaces with inflammatory material, producing a focal area of increased density—consolidation—often in a single lobe or segment, and sometimes with air bronchograms. So the combination of hyperinflation and peribronchial thickening points to bronchiolitis, whereas focal consolidation points to pneumonia.