Lacritin Level in Tear Film of Rheumatoid Arthritis Patients

The main ocular manifestation of rheumatoid arthritis is dry eye. Lacritin is a secreted glycoprotein of tear and when applied topically in rabbits, it increased the volume of basal tear secretion. So the aim of this study was to compare Lacritin level in rheumatoid arthritis (RA) and control group. This cross-sectional study was done on 40 patients with RA and 48 healthy subjects as a control group. In all participants, tear break-up time (TBUT) and Schirmer test with anesthesia were accomplished. Tear samples were collected directly from the inferior lateral tear meniscus and were immediately stored at -80 ° C until use. Lacritin level of tears were assessed by enzyme- linked immunosorbent assay. The mean age of participants was 44.7±16.3 and 43.3±18 years, respectively (p=0.70). Lacritin level in RA group (19.6±23.1 ng/ml) was significantly lower (31.9±23.3 ng/ml) than control (p=0.008). Pearson correlation between Lacritin level and TBUT, Schirmer value, ESR, and high-sensitivity C-creative protein (hs-CRP) in RA patients were not significant with p=0.27, 0.67, 0.09 and 0.07 accordingly. In early stages of RA in spite of normal tear production, Lacritin level decreased, however there is not any correlation between Lacritin level and TBUT, Schirmer value, ESR, and hs-CRP in these patients.