Histology. The heart was not remarkable. There was
mild fatty infiltration of the liver with scanty foci of
extramedullary erythropoiesis. No chronic venous
congestion was seen.
The histological appearances of the lungs were varied
(Fig. 2). In some areas there was conspicuous thickening
of the alveoli, occasionally with a concomitant
extravasation of red blood cells. Cystic emphysematous
areas were present at the periphery of the abnormal
alveoli. In other areas collapse had occurred. The
larger vessels and bronchi appeared normal. There was
no evidence of gross infection and inclusions were not
seen.