Antimitochondrial antibodies and their significance in diffuse and limited scleroderma

The increased prevalence of primary biliary cirrhosis (PBC) in Sjogren's syndrome and scleroderma has been described. We determined the frequency of antimitochondrial antibodies (AMA) in limited scleroderma, compared with diffuse scleroderma, and have considered their clinical significance because they are known to be related to PBC. Outpatients with scleroderma were prospectively tested for the presence of AMA and to determine whether they had evidence of liver disease both clinically and by laboratory parameters. Sixty-one patients with scleroderma were tested for AMA. Thirty of these had diffuse scleroderma. Four patients, all of whom had limited disease (4 of 31 or 13%), had positive AMA. Two had known primary biliary cirrhosis. The other two participants with positive antibodies had no evidence of liver disease when examined clinically, but no liver biopsies were performed. They have been followed for >2 years, without clinical evidence of PBC. Our findings agree with the literature that shows that 8% to 15% of patients with limited scleroderma have AMA. AMA did not occur in diffuse scleroderma in our population. Screening for the occurrence of PBC in scleroderma with antimitochondrial antibodies in patients without signs or symptoms of liver disease is unnecessary because at this time, we would not give ursodeoxycholic acid to scleroderma patients with positive AMA and normal alkaline phosphatases who had no symptoms of PBC.