Background: Patients with primary biliary cirrhosis (PBC) may have coincidental sicca syndrome (SS). The frequencies of SS and the occurrence of the Sjögren's-associated anti-Ro and -La antibodies in PBC patients have been reported at widely varying prevalences. This study investigated whether distinctive serologic characteristics are associated with SS in PBC.
Methods: Forty PBC patients and thirty patients with other types of liver cirrhosis were tested for SS and associated autoantibodies (ANA, AMA 2, anti-Ro, anti-La, anti-U1RNP-A, -C, -68 kD, and rheumatoid factors).
Results: Fourteen PBC patients (35%) complained of sicca symptoms, of whom 10 (25%) had a positive Schirmer-I test, and 7 (17.5%) had serologic characteristics similar to those of Sjögren's syndrome. Anti-52-kD Ro antibodies were positive in seven PBC/SS cases (p < 0.025). There was no anti-Ro positive PBC patient without SS. Three patients with PBC/SS with anti-52-kD Ro and anti-smooth-muscle antibodies developed lung fibrosis. No patient in the other cirrhosis group had SS or its characteristic autoantibody findings.
Conclusions: It was suggested that PBC and SS are frequently associated. Anti-52-kD Ro antibodies seem to be a characteristic serologic finding for SS in PBC, suggesting their pathogenic role in autoimmune sialadenitis.