What is the hallmark respiratory finding in croup?

• A. Productive cough with chest tightness
• B. Wheezing with tachycardia
• C. Inspiratory stridor without cough
• D. Inspiratory stridor with a barking cough

Answer: (D)

Croup causes swelling in the upper airway, specifically the larynx and upper trachea, which narrows the airway during inspiration. That upper-airway narrowing produces a high-pitched, harsh sound called inspiratory stridor. The irritation in the larynx and trachea also gives the characteristic barking cough. So the combination of inspiratory stridor and a barking cough is the classic, hallmark finding in croup. In contrast, a productive cough with chest tightness or wheezing with tachycardia points more toward lower airway or reactive airway conditions, not the typical croup picture. Occasionally stridor can occur without a cough, but the classic presentation clinicians look for is inspiratory stridor with a barking cough.