A 62-year-old non-smoker woman presents with worsening dyspnea and dry cough. HRCT shows bilateral, predominantly basal, subpleural ground-glass opacities with honeycombing and traction bronchiectasis. Lung biopsy shows temporal heterogeneity with areas of normal lung adjacent to fibrosis, fibroblastic foci, and honeycombing without significant inflammation. The diagnosis and histological pattern is:
- A Nonspecific interstitial pneumonia (NSIP) — homogeneous fibrosis
- B Usual interstitial pneumonia (UIP) — the pathological pattern of IPF ✓
- C Cryptogenic organizing pneumonia (COP) — alveolar fibroblast plugs
- D Desquamative interstitial pneumonia (DIP) — smoking-related
Explanation
Usual interstitial pneumonia (UIP) is the histological pattern underlying idiopathic pulmonary fibrosis (IPF). The hallmarks are: temporal heterogeneity (old dense fibrosis adjacent to normal lung), spatial heterogeneity (subpleural and basal predominance), fibroblastic foci (active fibrosis zones), and honeycombing. UIP carries the worst prognosis among ILDs (median survival 2-3 years). NSIP shows temporally homogeneous chronic inflammation and fibrosis, better prognosis, and is associated with CTDs. COP shows Masson bodies (intraluminal fibroblast plugs) in a peribronchovascular distribution. DIP shows uniform macrophage accumulation in alveoli in smokers.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
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Written and medically reviewed by the StethoPrep medical team.