Restrictive Lung Disease USMLE Step 1 Practice Question
A 48 year old man with a body mass index of 47 kg per m2 presents with morning headaches, daytime somnolence, and progressive dyspnea. Arterial blood gas shows chronic hypercapnia. Pulmonary function testing demonstrates reduced total lung capacity without airflow obstruction, and chest imaging shows no interstitial infiltrates. Which of the following is the most likely diagnosis?
Answer choices
- AAcute respiratory distress syndrome
- BPulmonary embolism
- CIdiopathic pulmonary fibrosis
- DObesity hypoventilation syndromeCorrect answer
- EHypersensitivity pneumonitis
- FObstructive sleep apnea
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