Abstract
Purpose :
Distinguishing ocular surface inflammation caused by Sjögren’s syndrome (SS) from that associated with non-autoimmune pathology is critical due to systemic implications of SS. Conjunctival inflammation in SS reduces goblet cell numbers and their expression of soluble mucins MUC5AC. In this study, we determined whether tear composition in SS patients is distinct with respect to MUC5AC and inflammatory cytokines and whether it can form the basis for differential diagnosis of SS versus non-SS pathology underlying ocular surface inflammation.
Methods :
In a prospective, observational case-control study on 62 patients with either a definitive diagnosis of SS-related or clinically significant non-SS related ocular surface inflammation, were examined along with age-matched healthy controls. Clinical evaluations included non-invasive tear break-up time (BUT), tear osmolarity, tear sampling, Schirmer’s test without anesthesia, and ocular surface staining (lissamine green for conjunctiva and fluorescein for cornea). Soluble mucins (MUC5AC) levels in tears were assessed with ELISA, and cytokines (IFN-g, TNF-α, IL-6, IL-17a, IL-1b, IL-8, IL-10, IL-12p70) were measured using a Luminex assay in a masked fashion.
Results :
Bulbar conjunctival lissamine green staining score was significantly greater in patients with SS- versus non-SS related ocular surface inflammation or controls, while conjunctival staining was associated with reduced tear MUC5AC (B= -17.8 ng/mL, 95% CI= -31.8 to -3.9, P = 0.01). Diagnosis of SS was significantly associated with increased tear IL-8 levels (HR=1.002, 95%CI= 1.000 to 1.003, P=0.03) and among patients stratified based on tear MUC5AC levels, compared to the control group, significantly increased tear IL-8 levels were detected in the SS but not the non-SS patients.
Conclusions :
The tear composition of SS patients is distinct with respect to goblet cell-specific MUC5AC and IL-8. Such distinction may facilitate differential diagnosis of SS-associated ocular surface pathology from non-SS inflammation.
This is a 2020 ARVO Annual Meeting abstract.