FIGURE 2.

Lung histopathology from two subjects demonstrating either capillaritis or prior alveolar haemorrhage. Subject 2: a) low-power view shows diffuse alveolar haemorrhage with filling of alveolar spaces by red blood cells. Focal lymphoid hyperplasia is present. Scale bar=500 µm. b) High-power view shows alveolar haemorrhage and prominent septal neutrophils (arrows) consistent with alveolar capillaritis. Scale bar=100 µm. Subject 4: c) low-power view shows bronchiolocentric airspace enlargement/cystic change, prominent lymphoid hyperplasia and increased haemosiderin-filled intra-alveolar macrophages. Scale bar=1 mm. d) High-power view shows lymphoid hyperplasia and haemosiderin-filled macrophages, indicative of prior alveolar haemorrhage. Scale bar=200 µm.