A 55-year-old nonsmoker woman presents with progressive dyspnea and bilateral basal fine crackles. HRCT shows bilateral basal-predominant subpleural honeycombing with traction bronchiectasis. BAL shows no predominant cell population. Surgical lung biopsy shows dense fibrosis with fibroblastic foci in a spatially heterogeneous pattern. The diagnosis and treatment of choice are:

• A Hypersensitivity pneumonitis; avoidance of antigen and steroids
• B Usual interstitial pneumonitis (UIP)/Idiopathic pulmonary fibrosis; antifibrotics (pirfenidone or nintedanib) ✓
• C Non-specific interstitial pneumonitis (NSIP); high-dose corticosteroids
• D Respiratory bronchiolitis-ILD; smoking cessation

Explanation

The HRCT pattern (basal subpleural honeycombing, traction bronchiectasis) and histology (dense heterogeneous fibrosis, fibroblastic foci — the hallmark of UIP) establish a diagnosis of IPF. IPF is treated with antifibrotic agents — pirfenidone (inhibits TGF-β) or nintedanib (triple tyrosine kinase inhibitor) — which slow FVC decline but do not reverse fibrosis (evidence from CAPACITY/ASCEND and INPULSIS trials). Steroids worsen outcomes in IPF. NSIP shows a more uniform, diffuse ground-glass pattern. HP requires exposure history.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.