Analysis of the relationship between anti-mitochondrial antibody subtypeⅡIgM and anti-centromere antibody IgG in primary biliary cirrhosis patients / 中华风湿病学杂志

ABSTRACT

Objective The aim of this study is to analyze the association between IgM anti-mitochon-drial antibody subtypeⅡ(AMA-M2-IgM) and the anti-centromere antibody IgG (ACA-IgG) in primary biliary cirrhosis (PBC) patients, and to investigate the clinical significance of M2-IgM and ACA-IgG in the diagnosis of PBC. Methods We selected 36 cases of PBC patients as research subjects whose AMA-IgG and AMA-M2-IgG were both negative. The M2-IgM positive rate in the ACA-IgG positive group and negative group was compared. We also analyzed the course of disease, pathological changes and the positive conversion rate of M2-IgG between the M2-IgM positive group and negative group. Results There were 9 cases of M2-IgM positive patients (64%) and 5 cases of M2-IgM negative patients (36%) in the ACA-IgG positive group. In the ACA-IgG negative group we found 3 cases of M2-IgM positive patients (14%) and 19 cases of M2-IgM negative patients (86%). So the M2-IgM positive rate in the ACA-IgG positive group was significantly higher than that of the ACA-IgG negative group (P=0.003). According to the tracking detection results, the M2-IgG positive conversion rate in the M2-IgM positive group was 67% (8 patients), which was significantly higher than the M2-IgM negative group 8%, (2 patients) (P=0.001). Conclusion M2-IgM is a specific antibody for PBC in the early stage, which presents earlier than M2-IgG. In the PBC patients whose AMA-IgG and AMA-M2-IgG antibodies are both negative, the M2-IgM positive rate is closely related to the ACA-IgG, so the ACA-IgG detection is very important in the early diagnosis of PBC. Therefore, we speculated that patients with ACA-IgG antibody are more susceptible to PBC.