71-year-old female suffered from a stenosis of the mitral valve due to rheumatic fever (specimen from autopsy).
- The architecture of the lung tissue is maintained. The capillaries are engorged with blood. Hemosiderin-laden macropages are present in alveolar spaces. Part of the alveolar septae show distinct fibrosis.
- Venules display narrowing of lumens and a homogenous eosinophilic appearance of the wall (venulosclerosis).
The lung tissue is firm and of brownish color due to deposits of hemosiderin-laden macrophages in alveolar spaces. The macroscopic findings associated with chronic congestion are thus also referred to as ‘brown induration’.