system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 5-year-old boy is brought to the emergency room by his parents due to worsening cough, fever, and difficulty breathing in the past 2 days. Physical exam reveals a barking cough and use of accessory muscles for breathing. After a full clinical workup, he is diagnosed with an upper respiratory infection caused by a parainfluenza virus. Which of the following findings in the clinical workup of this patient supported the diagnosis?
assistant
Chest radiograph showing narrowing of upper trachea and subglottis