High levels of immunoglobulin G levels (IgG) were associated with higher risk of cirrhosis among patients with co-occurring systemic lupus erythematosus-autoimmune hepatitis (SLE-AIH), according to recent data published in Arthritis Care & Research.
Autoimmune hepatitis is characterized by continuing hepatocellular necrosis and inflammation, which can lead to cirrhosis and liver failure. Researchers from the Asan Medical Center, University of Ulson College of Medicine in Seoul, South Korea, sought to identify the features of SLE-AIH that differ from those of primary AIH (P-AIH) and to evaluate the factors that affect outcomes in SLE-AIH patients.
High Yield Data Summary
- Patients with SLE-AIH were younger, with higher IgG levels, at the time of AIH diagnosis than those with primary AIH
- Serum IgG levels >2-fold greater than the upper limit of normal were associated with poor prognosis
The researchers collected data from 164 patients with P-AIH and 23 patients with SLE-AIH from an electronic database at a tertiary referral center between May 1995 and April 2014.
Patients were diagnosed with AIH based on the diagnostic scoring system for AIH, which was revised in 1999. Patients who were diagnosed with SLE fulfilled at least 4 of the 1997 revised American College of Rheumatology criteria.
SLE-AIH progression was defined as the occurrence of cirrhosis, hepatocellular carcinoma, liver transplantation, or death from hepatic failure.
At baseline, patients with SLE-AIH were generally younger than the P-AIH patients at the time of AIH diagnosis, and initial levels of serum IgG were higher among SLE-AIH patients than those with P-AIH.
Among the 23 patients with SLE-AIH, 8 developed cirrhosis. These patients had higher levels of serum IgG than the 15 patients who did not have cirrhosis (mean standard deviation: 4 077.4 ± 1 641.0 mg/dL vs 2 560.7 ± 932.2 mg/dL; P=.017).
The researchers found that a serum IgG level of 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=.026).
“We found that that the age of SLE-AIH patients at the time of AIH diagnosis was younger than that of P-AIH patients, which is consistent with the finding of previous reports,” the authors of the study wrote. “The difference in age between the P-AIH and SLE-AIH groups may be affected partly by a delay in detecting P-AIH.”
Summary and Clinical Applicability
The current study found that higher IgG levels were associated with a 2-fold higher risk of cirrhosis among SLE-AIH patients. The researchers note that anti-inflammatory immunosuppressive therapies such as prednisolone or azathioprine are successful in 65% to 80% of AIH cases, although treatment outcomes for SLE-AIH patients remain unclear.
“Making any conclusion about the long-term prognosis is difficult, because only a small number of SLE-AIH patients were included in this study,” the authors wrote. “Further research with a large number of SLE-AIH patients is needed to identify the prognosis of SLE-AIH in comparison to P-AIH.”
Limitations and Disclosures
The researchers noted that the current study was retrospective in nature and that distinguishing between SLE-AIH and lupus hepatitis can be difficult, which suggests that some of the patients in the cohort may have had lupus hepatitis.
Lim DH, Kim YG, Lee D, et al. Immunoglobulin G levels as a prognostic factor for autoimmune hepatitis combined with systemic lupus erythematosus. Arthrit Care Res. 2016;68(7):995-1002. doi: 10.1002/acr.228800.