Genetic distinctions and clinical characteristics of type 1 autoimmune hepatitis in Taiwan

The genetic features in Eastern autoimmune hepatitis (AIH) patients are seldom surveyed. Previous studies on the linking of human leukocyte antigen (HLA) with AIH have highlighted the necessity of evaluating ethnically homogeneous populations, but no investigation for Taiwanese patients has been reported. This study aims to evaluate the HLA characteristics of Taiwanese AIH patients.

Medical records of Taiwanese AIH patients (1990-2005) were reviewed and the correlation of HLA alleles with disease susceptibility and severity was surveyed. HLA typing was performed by polymerase chain reaction amplification with sequence-specific primers.

Unlike the Western reports, HLA-A1, B8, and DR3 were not identified. The most frequently encountered was A11 (48.6%). DR4 (35.1%) was less often found than that in Japanese and Chinese series. As compared with Taiwanese normal controls, the frequency of B35 was significantly increased (18.9% vs. 5.4%, odds ratio = 4.072, Pc < 0.001). B35-postitive patients also had higher pretreatment serum aminotransferase concentrations. More of the patients were cholestatic and responded well to a lower dose of prednisolone as compared with those reported in the Western literature.

HLA-B35 plays a distinct role in susceptibility and severity of AIH in Taiwan. Racial genetic backgrounds may account for the different results.