[Presence of SLA/LP autoantibodies in patients with primary biliary cirrhosis as a marker for secondary autoimmune hepatitis (overlap syndrome)]

Abstract

Background and objective: The aim of this study was to evaluate whether the presence of SLA/LP-autoantibodies in PBC-patients gives evidence for a secondary AIH, also called AIH/PBC-overlap-syndrome.

Patients and methods: Out of 233 consecutive patients with PBC who had been followed between October 1980 and April 2000, we evaluated the data of anti-SLA/LP-positive patients and compared them to patients with an anti-SLA/LP-negative AIH/PBC overlap syndrome as well as to patients with a classical course of AIH and PBC.

Results: In total we could identify nine PBC patients with anti-SLA/LP antibodies (six women/three men) or 3.9% of the study population, Anti-SLA/LP-positive PBC patients were slightly younger at diagnosis in comparison to anti-SLA/LP-negative PBC-patients (49.9 vs. 53.2 years). Transaminases and gamma-globulins were significantly higher in anti-SLA/LP-positive PBC-patients in comparison to anti-SLA/LP-negative PBC-patients (mean: 235 vs. 55 IU/l and 27.6 vs. 19.5 g/l). Anti-SLA/LP-positive patients significantly more frequently had an HLA-type that is characteristic for AIH (B8; DR3; DR4). Immunosuppressive therapy reduced inflammatory activity and cholestasis significantly. Relapses were frequent after reduction or discontinuation of immunosuppressive therapy.

Conclusion: The presence of SLA/LP autoantibodies in PBC patients has a high specificity for a secondary AIH (AIH/PBC overlap syndrome). These patients have a good response to immunosuppressive therapy. The autoantibody profile and immunogenetics may help in future to identify PBC patients that benefit most from immunosuppressive therapy.