Prognostic factors for the clinical severity of keratoconjunctivitis sicca in patients with Sjogren's syndrome

Aims To determine whether prognostic immunological profiles predict the severity of keratoconjunctivitis sicca (KCS) in patients with Sjogren's syndrome (SS). Methods 121 patients diagnosed with SS and followed for at least 1 year were enrolled in this study. Patients were allocated to either a mild KCS group (Mi-KCS; n = 65) or to a moderate to severe KCS group (MS-KCS; n = 56) based on the Oxford scheme and response to treatment. These groups were each sub-divided into two groups based on the clinical severity of KCS and the presence of associated rheumatic disease (primary SS vs secondary SS). Anti-Ro/anti-La antibody, rheumatoid factor and tear interleukin (IL)-17 levels and Schirmer test results were compared between each group. Results Anti-Ro/SSA antibody and anti-La/SSB antibody concentrations were significantly higher in the MS-KCS group than in the Mi-KCS group for total and primary SS. The presence of anti-La/SSB antibody was significantly higher in the MS-KCS than the Mi-KCS group for total and primary SS. The mean tear IL-17 concentration in the MS-KCS group was significantly higher than in the Mi-KCS group for both total SS and primary SS patients. Conclusion Serum anti-La/SSB antibody, serum anti-Ro/SSA antibody and tear IL-17 are likely to be strongly involved in the clinical severity of KCS in patients with primary SS.