COPD USMLE Step 1 Practice Question
A 68-year-old man with a 50 pack-year smoking history presents with progressive dyspnea and 12-pound weight loss over three months. Vital signs show BP 142/88, HR 102, RR 22, SpO2 88% on room air. Physical examination reveals barrel chest, pursed-lip breathing, and accessory muscle use. Chest X-ray demonstrates hyperinflation with flattened diaphragms. FEV1/FVC ratio is 0.58. He denies orthopnea. Which lung distribution pattern is most characteristic of smoking-related emphysema?
Answer choices
- ABronchial mucus plugging with eosinophilic crystals
- BNoncaseating granulomas concentrated in hilar nodes
- CCentriacinar destruction involving the upper lobesCorrect answer
- DPanacinar destruction involving the lower lobes
- EDiffuse fibrotic change with honeycomb lung
- FBasilar-predominant airway wall thickening with bronchial dilation
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.