Make the Diagnosis: Spring 2023

An 11-year-old girl with no significant past medical or surgical history presented to her PCP after approximately 2 months of progressive hoarseness and exertional stridor and dyspnea. During this time, she had begun to cough up thick mucus that felt like it was stuck in her throat, but she had not had any recent illness or viral infection. In addition to difficulty breathing, she had reported “throwing up in her mouth” every day and experiencing pain with swallowing.

She had no history of choking or coughing with eating and drinking. She had never passed out due to shortness of breath, but she was no longer able to compete in soccer at the level she had previously enjoyed. She could only play for brief stints and then had to come out to rest. Her PCP diagnosed her with asthma and started her on albuterol and QVAR 40 to be used on an as-needed basis. When inhalers did not help, she was referred to Pulmonology where pulmonary function testing revealed limited flow on both inspiratory and expiratory flow volume curves. ENT evaluation was noteworthy for mild biphasic stridor but non-labored breathing. Nasopharyngoscopy was unremarkable with normal vocal fold movement bilaterally.

What is the most likely diagnosis?