It’s flu season…how can you tell if your patient presenting with cough and fever has pneumonia? 1. The Clinical Exam: decreased air entry on one side? crackles? dullness to percussion? increased tactile fremitus? whispered pectoriloquy? egophony? (yikes) 2. The CXR: there may be some fluffy white stuff?
Keep calm, there is a tool that can help you sort it out — Ultrasound: “The stethoscope of the 21st century”.(1)
Pneumonia will appear in one of 3 ways on ultrasound (1):
The Shred Sign: a subpleural consolidation with an irregular border between aerated and consolidated lung.
The Tissue-like Sign: it looks like liver parenchyma with dynamic air bronchograms (echogenic lines that vary with respiration).
The Interstitial pattern/B lines: it tends to be focal but can be bilateral in cases such as aspiration pneumonia.
Let’s go over a few cases from this past month that illustrate this…
Case 1: 33 yo F presenting with fever and cough. The ultrasound clip shows The Shred Sign: a subpleural consolidation in the LLL. The corresponding CXR, taken hours later, follows.
Case 2: 90 yo F presents with fever and cough. The ultrasound clip shows The Tissue-like Sign: a LLL consolidation with a small parapneumonic effusion. The corresponding CXR follows.
Case 3: 50 yo male presents with a runny nose, low grade temp and right sided pleuritic chest pain. The ultrasound clip shows the Interstitial pattern/focal B-lines: representing a RML pneumonia. The corresponding CXR follows.
Case 3b: 90 yo F presents with fever, cough and SOB. The ultrasound clip shows the Interstitial sign/bilateral B lines: representing a bilateral pneumonia. The corresponding CXR follows.
These 3 cases highlight the advantages of using lung ultrasound to diagnose pneumonia. It’s more sensitive than CXR (2) and it often leads to faster diagnosis and management.
Happy scanning this holiday season!
(1) Lichtenstein D, van Hooland S, Elbers P, Malbrain ML. Ten good reasons to practice ultrasound in critical care. Anaesthesiol Intensive Ther 2014 Nov-Dec;46(5):323-335.
(2) Liu XL, Lian R, Tao YK, Gu CD, Zhang GQ. Lung ultrasonography: an effective way to diagnose community-acquired pneumonia. Emerg Med J 2014 Aug 20.