Abstract: Objective To investigate the clinicopathological features of Polygonum multiflorum-associated drug induce liver injury (PM-DILI) and provide pathological evidence for clinical diagnosis and treatment.Methods Eight PM-DILI patients with complete clinical data including liver function, autoimmune antibody tests, clinical epidemiological investigations and other lab tests were enrolled. Liver biopsy was performed in all subjects. The pathological features of hepatic tissue were observed by ematoxylin-eosin staining, reticular fiber staining, Masson’s trichrome staining, special staining of iron and copper, and immunohistochemical staining.Results The male to female ratio of the patients was 1∶1, and the average age was 43. Six cases were diagnosed as acute PM-DILI and 2 were diagnosed as chronic PM-DILI. Serological abnormalities at admission mainly included elevated transaminases levels (87.5%, 7/8) and cholestasis (87.5%, 7/8). The main histopathological changes were focal necrosis (100%, 8/8), interface hepatitis (62.5%, 5/8) and confluent necrosis (50%, 4/8). Confluent necrosis mainly occurred in the acinar zone 3, without or with a few inflammatory cell infiltration. Cholestasis (62.5%, 5/8) mainly occurred in the acinar zone 3, without or with a few inflammatory cell infiltration, and centralphlebitis (37.5%, 3/8). Liver fibrosis or even cirrhosis (25.0%, 2/8) might occur in those with a long disease duration.Conclusion There are some certain histopathology features in PM-DILI, acute cholestasis and hepatocyte necrosis in the acinar zone 3 are the main histological manifestations. Vascular injury such as phlebitis may occur in severe cases. Liver biopsy is helpful for diagnosing PM-DILI and evaluating the severity.

Key words: Polygonum multiflorum, Drug-induced liver injury, Pathology