Significance of liver histopathological examination in diagnosis and treatment of drug-induced liver injury

The incidence rate of drug-induced liver injury (DILI) tends to increase in recent years, and early accurate diagnosis and evaluation of the degree of liver injury are great challenges in diagnosis and treatment. The pathomorphological features of DILI are determined by the structure and metabolic features of hepatic lobules. The basis of pathological injury pattern is injury of related targets, i. e., hepatocytes, biliary epithelium, and blood vessel endothelium, which determines the distinct features of DILI. Although DILI has various pathological features, it has major injury patterns of acute hepatitis type, chronic hepatitis type, acute cholestatic type, chronic cholestatic type, and cholestatic hepatitis type. The degree of the pathological injury of DILI is associated with the disease severity and prognosis of patients, and pathology helps to identify small bile duct injury and vascular endothelial injury caused by drugs as early as possible. The liver histological features of DILI overlap with other diseases, and related clinical indices should be used to make an objective, accurate, and timely diagnosis of DILI. This article reviews the pathomorphological features and patterns of DILI and elaborates on the significance of liver histological examination in the diagnosis and treatment of DILI.