[Pathology of disseminated intravascular coagulation]

We reviewed the histopathologic characteristics of DIC in autopsy cases. Typical hyaline microthrombi preferentially occurred in renal glomeruli, pulmonary microvasculature, splenic sinuses, adrenocortical capillaries and others, occasionally associated with degenerative or necrotic changes of parenchymal cells of respective organs partly due to ischemic effects of microthrombi and thromboemboli. Investigating the pathogenesis of microthrombi in hepatic sinusoids of rats intravenously injected with LPS (5 mg/kg B.W.) using double immunohistochemical reactions for LPS and fibrinogen, and electron microscopic observations, fibrin thrombi were largely formed around small necrotic foci of hepatocytes 1 hr after injection, which occurred in the very close vicinity to Kupffer cells phagocytizing LPS, and on the cytoplasmic surface of swollen Kupffer cells lading LPS 3 hr after injection. Neutrophils always aggregated in the necrotic foci. Thus, activated Kupffer cells by LPS seemed to play a central role in the development of fibrin thrombi in hepatic sinusoids of endotoxemic rats, through the activation of coagulation system probably via the expression of tissue factor by activated Kupffer cells.