Table 1

UIP in IPF

Clinical features	Radiological features	Histopathological features
▸ Age greater than 60 years ▸ More frequent in men ▸ Smoking history common ▸ Dyspnoea longer then 3 months ▸ Dry, non-productive cough ▸ Restrictive pattern of respiratory impairment common ▸ Inhalational exposures uncommon ▸ Digital clubbing, common in advanced disease ▸ Oxygen desaturation with exercise common	▸ Subpleural and basal predominance ▸ Progressive gradient toward bases ▸ Reticular abnormalities ▸ Traction bronchiectasis ▸ Subpleural honeycomb cysts (necessary for confident radiological diagnosis) ▸ Minimal ground-glass opacities: common in areas of reticulation, but never extensive	▸ Spatial heterogeneity ▸ Temporal heterogeneity ▸ Fibroblastic foci common ▸ Peripheral lobular distribution commonly present ▸ Microscopic honeycomb remodelling ▸ Smooth muscle in fibrosis