Figure 7.3.6.

Phospholipidosis due to prolonged amiodarone administration. Amiodarone blocks lysosomal phospholipases, leading to the accumulation of phospholipids in many organs. In the lung this is manifest as endogenous lipid pneumonia. (A) By light microscopy the alveoli are filled with foamy macrophages. (B) Electron micrograph showing an alveolar macrophage (top) packed with osmiophilic lamellar bodies. The macrophage covers several type II pneumocytes that, in addition to their normal surfactant inclusions (arrows), contain large lamellated drug-induced inclusions (asterisks), which are also seen in capillary endothelial cells. C, capillary.

(Reproduced with permission from Costa-Jussa et al. (1984).⁵⁰)