Pleural friction rub is described as what sound, and what condition is it indicative of?

• A. Pleural friction rub sounds like a grating or squeaking due to inflamed pleural layers, indicative of pneumonia
• B. A moist, bubbling sound typical of congestive heart failure
• C. High-pitched wheeze heard with asthma
• D. A dull sound with percussion in COPD

Answer: (A)

Pleural friction rub is a high-pitched, grating or squeaking sound heard when the inflamed pleural surfaces rub together during breathing. This finding points to pleuritis, which can be associated with pneumonia or other pleural inflammation. It’s not a crackling or bubbling sound from fluid in the airways (like in congestive heart failure), not a wheeze from bronchospasm (asthma), and not a dull percussion note seen with COPD. The friction rub reflects irritation of the pleura rather than changes inside the airways or lung parenchyma.