Histology USMLE Step 1 Practice Question
A 60-year-old man presents with a 2-year history of progressive dyspnea and chronic nonproductive cough. He denies occupational exposures, smoking history, and medications. Vital signs show BP 138/82, HR 98, RR 22, and SpO2 88% on room air. Chest X-ray demonstrates bilateral lower lobe reticular opacities with traction bronchiectasis. Transbronchial lung biopsy reveals temporal heterogeneity of fibrosis, patchy subpleural and paraseptal fibroblast proliferation, thickened alveolar septa with chronic inflammation, and early-stage honeycomb change. Which histologic pattern is most consistent with this clinical presentation?
Answer choices
- ADiffuse alveolar damage with hyaline membranes and acute interstitial pneumonia
- BRespiratory bronchiolitis with peribronchiolar pigmented macrophages and minimal interstitial inflammation
- CUsual interstitial pneumonia (UIP) pattern with temporal and spatial heterogeneityCorrect answer
- DPulmonary edema with alveolar capillary engorgement and proteinaceous fluid in alveolar spaces
- EEmphysematous changes with loss of alveolar walls and enlarged air spaces
- FOrganizing pneumonia with Masson bodies and fibroblastic proliferation filling alveolar lumens
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