Table 3

UIP in CHrHP

Clinical features	Radiological features	Histopathological features
▸ Middle age to older individuals ▸ Slowly progressive dyspnoea ▸ Cough frequent, often productive ▸ Exposure history, frequent, with focused questioning or home visit ▸ Positive precipitin antibodies, inconsistent	▸ Reticular pattern with traction bronchiectasis ▸ Ground-glass opacities, common ▸ Mid and upper lung zones commonly affected in a bronchovascular distribution with resulting micronodules ▸ Non-basilar distribution common ▸ Mosaic attenuation ▸ Irregular bronchovascular bundles ▸ Subpleural honeycomb cysts, not always basilar	▸ Patchy fibrosis along the bronchovascular bundle with rare fibroblast foci ▸ Individual interstitial giant cells, some with cholesterol clefts. ▸ Honeycomb cysts (lower and upper lobes) ▸ Extensive peribronchiolar metaplasia. ▸ Bridging fibrosis across lobules