Pathological features and pathological diagnosis of drug-induced liver injury

Based on liver histology, drug-induced liver injury (DILI) is classified as various pathological types of inflammatory necrosis, cholestasis, fatty degeneration and fatty liver disease, vascular injury, and minimal lesion. Histopathological examination is required for further differential diagnosis in suspected cases of DILI, liver injury that cannot be explained by DILI monogenesis, DILI cases with a history of exposure to various drugs in which the specific drug causing liver injury cannot be determined, DILI cases with unsatisfactory treatment outcome, and chronic DILI, and histopathological examination can also be used to evaluate the severity and prognosis of DILI. Since liver lesions are unevenly distributed in DILI, adequate tissue samples are needed to reduce sampling error. The histopathological manifestation of liver injury diseases has the features of "one cause with multiple results and one result with multiple causes", and a combination of pathological examination and clinical symptoms can help to make a confirmed diagnosis, suggesting that clinicopathological discussion is of great importance in the histological diagnosis of DILI.