Clinicopathological basis of liver failure

Liver failure is a group of hepatocyte dysfunctions caused by severe synthetic and metabolic disorders and has a high mortality rate. Histopathology has great clinical significance in the diagnosis, classification, and prognostic evaluation of liver failure. Extensive hepatocyte death and hepatocyte regeneration run through the whole clinicopathological process of liver failure, and necrosis is the major type of cell death in liver failure and is often accompanied by other types such as apoptosis, pyroptosis, and autophagy. Each type of liver failure has its own pathological features. Acute liver failure emphasizes consistent massive or submassive necrosis caused by one hit; subacute liver failure has the features of submassive or massive liver necrosis due to new and old lesions caused by multiple hits; acute-on-chronic live failure shows extensive hepatocyte necrosis caused by one or multiple hits on the basis of chronic liver disease; chronic liver failure has the histological features of liver cirrhosis with small nodules or mixed large-small nodules, compact and wide fibrous septa mainly composed of collagen type I, Laennec stage ( mainly F4 c) , significant reductions in the number and function of liver parenchymal cells, and marked intrahepatic vascular structural abnormalities and blood circulation disorders, as well as liver inflammatory lesions. Hepatocyte death triggers the recruitment of a large number of inflammatory cells and the overactivation of Kupffer cells and stimulates immune-mediated liver injury and systemic inflammatory response syndrome caused by inflammation activation, which are the main pathophysiological mechanisms of multiple organ failure caused by liver failure.