Primary biliary cirrhosis:What do autoantibodies tell us?

Primary biliary cirrhosis(PBC) is a chronic,progressive,cholestatic,organ-specific autoimmune disease of unknown etiology.It predominantly affects middle-aged women,and is characterized by autoimmune-mediated destruction of small-and medium-size intrahepatic bile ducts,portal inflammation and progressive scarring,which without proper treatment can ultimately lead to fibrosis and hepatic failure.Serum autoantibodies are crucial tools for differential diagnosis of PBC.While it is currently accepted that antimitochondrial antibodies are the most important serological markers of PBC,during the last five decades more than sixty autoantibodies have been explored in these patients,some of which had previously been thought to be specific for other autoimmune diseases.

Primary biliary cirrhosis-specific autoantibodies in first degree relatives of Greek primary biliary cirrhosis patients

AIM:To determine the prevalence and significance of primary biliary cirrhosis (PBC)-specific autoantibodies in firstdegree relatives (FDRs) of Greek PBC patients. METHODS:The presence of antimitochondrial antibodies (AMA) and PBCspecific antinuclear antibodies (ANA) were determined using indirect immunofluores-cence assays, dot-blot assays, and molecularly based enzyme-linked immunosorbent assays in 101 asymp-tomatic for liver-related symptoms FDRs of 44 PBCpatients. In order to specify our results, the same investigation was performed in 40 healthy controls and in a disease control group consisting of 40 asymptomatic for liver-related symptoms FDRs of patients with other autoimmune liver diseases namely, autoimmune hepati-tis-1 or primary sclerosing cholangitis (AIH-1/PSC). RESULTS: AMA positivity was observed in 19 (only 4 with abnormal liver function tests) FDRs of PBC patients and none of the healthy controls. The preva-lence of AMA was significantly higher in FDRs of PBC patients than in AIH-1/PSC FDRs and healthy controls [18.8%, 95% confidence interval (CI):12%-28.1% vs 2.5%, 95% CI:0.1%-14.7%, P = 0.01; 18.8%, 95% CI:12%-28.1% vs 0%, 95% CI: 0%-10.9%, P = 0.003, respectively]. PBC-specific ANA positivity was observed in only one FDR from a PSC patient. Multivariate analysis showed that having a proband with PBC independently associated with AMA positivity (odds ratio: 11.24, 95% CI:1.27-25.34, P = 0.03) whereas among the investigated comorbidities and risk factors, a positive past history for urinary tract infections (UTI) was also independently associated with AMA detection in FDRs of PBC patients (odds ratio:3.92, 95% CI:1.25-12.35,P = 0.02). CONCLUSION:In FDRs of Greek PBC patients, AMA prevalence is significantly increased and independently associated with past UTI. PBC-specific ANA were not detected in anyone of PBC FDRs.

Role of autoantibodies in the clinical management of primary biliary cholangitis

Primary biliary cholangitis(PBC)is a chronic cholestatic liver disease characterized by immune-driven destruction of small intrahepatic bile ducts leading a proportion of patients to hepatic failure over the years.Diagnosis at early stages in concert with ursodeoxycholic acid treatment has been linked with prevention of disease progression in the majority of cases.Diagnosis of PBC in a patient with cholestasis relies on the detection of disease-specific autoantibodies,including anti-mitochondrial antibodies,and disease-specific anti-nuclear antibodies targeting sp100 and gp210.These autoantibodies assist the diagnosis of the disease,and are amongst few autoantibodies the presence of which is included in the diagnostic criteria of the disease.They have also become important tools evaluating disease prognosis.Herein,we summarize existing data on detection of PBC-related autoantibodies and their clinical significance.Moreover,we provide insight on novel autoantibodies and their possible prognostic role in PBC patients.