[Clinicopathological analysis of anti-mitochondrial antibody negative primary biliary cholangitis-autoimmune...

Objective: To explore the clinicopathological features of anti-mitochondrial antibody (AMA) negative and positive patients with primary biliary cholangitis-autoimmune hepatitis overlap syndrome (PBC-AIH OS). Methods: Seventy-four cases diagnosed as PBC-AIH OS from June 2017 to April 2018 were enrolled in this study. Among them, forty cases were AMA negative (negative group) and thirty-four cases were AMA positive (positive group). The clinical manifestations, serum biochemical indexes, immunological indexes and histological data of the negative group were compared with the positive group. Mann-Whitney U test and theχ (2)test were used for statistical analysis. Results: There was no significant difference in sex, age, clinical manifestations and major liver function indexes (ALT, AST, ALP, GGT, TB, DB) between the negative group and positive group (P> 0.05). The level of IgM in the negative group (1.68 ± 0.87) was significantly lower than positive group (3.77 ± 2.88)(P< 0.05). The positive rates of antinuclear antibodies (ANA) and gp-210 antibodies was lower than positive group (P< 0.05). There were no significant differences in the stages of inflammation and fibrosis between the two groups (P> 0.05), and the bile duct injury was more significant in the negative than positive group (P< 0.05). Conclusion: The serum IgM level of AMA-negative PBC-AIH OS is low, and immunological antibody is often negative, which makes bile duct injury apparent in liver histology. A liver biopsy should be carried out as soon as possible for early diagnosis and treatment.