Pneumonia is an infection that inflames the alveoli and fills them with fluid. This extra fluid creates unilateral or bilateral B-lines depending if one or both lungs are affected.
The fluid or pus-filled alveoli also cause a productive cough with colored phlegm, fever, chills, and difficulty breathing.
Ultrasound Profile of Pneumonia:
- Shred sign
- Consolidated lung tissue with dynamic air bronchograms
- B-lines: unilateral (bacterial) or bilateral (viral)
- Decreased lung sliding depending on severity
- Small pleural effusion depending on severity
Even the most experienced ultrasound practitioners have difficulty distinguishing pneumonia from atelectasis using ultrasound alone. Thus, a clear clinical picture is necessary before determining the true cause of lung consolidation. The table below outlines some of the key differentiating factors between pneumonia and atelectasis.
| Pneumonia | Atelectasis | |
| US Findings | – Consolidation pattern – Shred sign – Dynamic bronchograms – Possible pleural effusion (parapneumonic effusion) | – Consolidation pattern – Static air bronchograms |
| Distinguishing clinical features | – Fever and chills – Cough with colored mucous or blood – Severe Malaise – Crackles and breath sounds | – Obstruction to airway – Acute dyspnea – Mucous plug in Bronchus |