Is prevalence of PBC underestimated in patients with systemic sclerosis?

Clinically significant primary biliary cirrhosis occurs in 2.5% of patients with systemic sclerosis. Primary biliary cirrhosis-specific autoantibodies include anti-mitochondrial, anti-glycoprotein 210, and anti-sp100 antibodies. The majority of asymptomatic anti-mitochondrial-positive subjects express histological features of primary biliary cirrhosis. Early detection of primary biliary cirrhosis is important, as timely introduction of ursodeoxycholic acid may improve prognosis. The aim was to assess the prevalence of MIT3 IgG-anti-mitochondrial, gp210, sp100 and other autoantibodies in patients with systemic sclerosis and compare the clinical and biochemical parameters in those who are primary biliary cirrhosis-specific autoantibodies positive and negative.

Fifty-two consecutive patients with systemic sclerosis were included. Thirty-three suffered from limited skin SS and 19 from diffuse SS.

Eight (15%) patients with systemic sclerosis tested positive for primary biliary cirrhosis-specific autoantibodies. No significant differences were observed between primary biliary cirrhosis-specific autoantibodies positive and negative subjects in terms of various demographic, clinical or biochemical features. A trend towards increased prevalence of chronic fatigue in primary biliary cirrhosis-specific autoantibodies positive patients was observed.

Primary biliary cirrhosis-specific autoantibodies were detected in 15% of the systemic sclerosis patients. Since patients with primary biliary cirrhosis-specific antibodies are at high-risk or do suffer from primary biliary cirrhosis, screening for primary biliary cirrhosis-specific autoantibodies may be considered during routine assessment of systemic sclerosis.