Primary biliary cholangitis with inflammation involving zone 3 of the liver has a poor response to ursodeoxycholic acid treatment: a retrospective cohort study

Primary biliary cholangitis (PBC) is a chronic, progressive autoimmune disease characterized by the destruction of intrahepatic biliary epithelial cells, progressive fibrosis, and the expression of anti-mitochondrial antibodies. Although ursodeoxycholic acid (UDCA) can significantly improve liver biochemical parameters and delay disease progression as a first-line treatment, 40% of patients still have a poor response to UDCA treatment. Inflammation involving different regions of the hepatic lobule may be related to the therapeutic effect of UDCA. The aim of this study is to investigate the relationship between liver inflammation zones and UDCA treatment response in PBC patients, and to further analyze the predictive value of liver lobular zones for treatment response. This is a single-center retrospective cohort study. A total of 121 PBC patients diagnosed in the Second Affiliated Hospital of Kunming Medical University from December 2014 to March 2024 were enrolled. Drawing on the Rappaport hepatic acinar zoning model and combining with the Bahar Halpern theory, the liver lobules were divided into three regions. The relationship between different divisions of liver lobules involved in PBC and the therapeutic effect of UDCA was studied, and the Nakanuma grading system was applied to evaluate the histological features. logistic regression analysis was used to investigate the association between lobular regions involved and non-response to UDCA treatment. In univariate analysis, gender, jaundice, ascites and lesion involvement were statistically significant (P < 0.05), and these factors may be independent risk factors for non-response to UDCA.Lesions zone 3 involvement (the area around the central vein) were significantly associated with a poor response to UDCA treatment (OR: 3.632, CI95%: 1.130-11.677, P = 0.030). In addition, the presence of ascites at baseline was also an important risk factor for poor response to UDCA treatment (OR: 5.475, CI95%: 1.221–24.551, P = 0.026). The pathological changes involving zone 3 of the hepatic lobule may be an important pathological marker for predicting the poor response of PBC patients to UDCA.