Immunoglobulin G Levels as a Prognostic Factor for Autoimmune Hepatitis Combined With Systemic Lupus Erythematosus.

OBJECTIVE: Autoimmune hepatitis (AIH) is a chronic progressive liver disease characterized by circulating autoantibodies and hyperglobulinemia. This study was conducted to identify the features of AIH accompanied by systemic lupus erythematosus (SLE-AIH) that differ from those of primary AIH (P-AIH), and to evaluate factors that affect the outcome for SLE-AIH patients.

METHODS: From May 1995 to April 2014, clinical data (including liver pathology) from 164 patients with P-AIH and 23 patients with SLE-AIH were collected from an electronic database at a tertiary referral center. AIH was diagnosed according to the diagnostic scoring system for AIH (revised in 1999). SLE patients fulfilled at least 4 of the 1997 revised American College of Rheumatology criteria. Progression was defined as occurrence of cirrhosis, hepatocellular carcinoma, liver transplantation, or death from hepatic failure.

RESULTS: The age at the time of AIH diagnosis was lower and initial levels of serum IgG were higher in SLE-AIH than in P-AIH patients. Progression was more common in P-AIH, and hepatocellular carcinoma, liver transplantation, or death occurred only in P-AIH patients. Among 23 patients with SLE-AIH, 8 with cirrhosis had higher levels of serum IgG than 15 patients without cirrhosis (mean ± SD 4,077.4 ± 1,641.0 mg/dl and 2,560.7 ± 932.2 mg/dl, respectively; P = 0.017). Moreover, a serum IgG level more than 2-fold the upper normal limit was associated with a high risk of cirrhosis in SLE-AIH (odds ratio 11.00 [95% confidence interval 1.420-85.201]; P = 0.026).

CONCLUSION: Initially high levels of serum IgG are a poor prognostic factor for SLE-AIH. Additionally, the long-term outcome for SLE-AIH might be better than for P-AIH.