Asthma USMLE Step 1 Practice Question
A 17-year-old girl with episodic wheezing, chest tightness, and cough triggered by cat exposure and exercise presents with HR 102 bpm, RR 22/min, and SpO2 98% on room air. Symptoms resolve within 15 minutes of inhaled albuterol. Spirometry shows FEV1/FVC ratio of 0.68 that improves 12% post-bronchodilator. She denies fever, productive cough, or orthopnea. Which of the following best explains the airflow limitation in this patient?
Answer choices
- AIrreversible destruction of alveolar septa
- BObliteration of small airways by granulation tissue
- CReversible bronchial hyperresponsiveness with smooth muscle constriction and mucus pluggingCorrect answer
- DFibrotic thickening of the interstitium with reduced compliance
- EPleural inflammation causing reduced chest wall expansion
- FChronic inflammation with permanent airway wall remodeling and loss of elastic recoil
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations — plus adaptive practice that targets your weak areas — with a free MedBoardPRO account.