[Clinicopathological analysis of anti-mitochondrial antibody negative primary biliary cholangitis-autoimmune hepatitis overlap syndrome].

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.