Background: Rheumatologists are increasingly being referred to ophthalmologists for the evaluation of systemic causes or treatment of non-infectious scleritis. In this scenario, the diagnosis of GPA is sometimes made. Although ocular involvement in this disease is well known, there is still little data on the clinical-epidemiological aspects that increase the suspicion of GPA in the face of non-infectious scleritis or even on phenotypic differences in the disease when its first manifestation is the eye.

Objectives: To identify elements that will help rheumatologists recognize patients with GPA when they are referred for non-infectious scleritis, the main objective was to compare the clinical-epidemiological and scleritis-related characteristics of patients with GPA and scleritis (S-GPA) with those of patients with non-infectious scleritis without a systemic autoimmune etiology. Due to a lack of consensus, this group is referred to as immune-mediated scleritis (IMS). Among patients with S-GPA, we will also assess whether there is a phenotypic difference between those whose diagnosis of scleritis led to the diagnosis of GPA and those who developed scleritis with the disease already established.

Methods: This was a retrospective observational study that assessed adult patients diagnosed with scleritis and followed up in the Vasculitis or Autoimmune Eye Disease outpatient clinics of a tertiary rheumatology service throughout 2023. Patients with scleritis as a manifestation of GPA (according to the ACR/EULAR criteria of 2022) and those with IMS (defined after 6 months of combined clinical and laboratory evaluation by the ophthalmology and rheumatology teams) were included and compared. The statistical tests used were Fisher’s exact test and Mann-Whitney test, and the analysis was performed using R 4.3.2 software.

Results: Nineteen patients were selected: 7 with GPA Scleritis (GPA-S) and 12 with a diagnosis of IMS. The demographic and scleritis-related characteristics are shown in Table 1. No demographic data or data related to the type of scleritis (anterior, posterior, diffuse, or necrotizing) differed between the two groups.

When a comparison was made between the GPA-S group, no statistical difference was found between those whose diagnosis of GPA was based on an ophthalmological diagnosis of noninfectious scleritis and those with scleritis during the course of the disease in the following aspects: age at diagnosis (p: 0,4), female sex (p: 1,0), ANCA + (p: 1,0), glomerular disease (p: 0,1429), lung disease (p: 0,4857), skin disease (p: 1,0), central nervous system involvement (p: 0,4286) and ear, nose, and throat involvement (p: 1,0).

Conclusion: In our sample, no demographic findings or those related to the type of scleritis were more associated with GPA scleritis than IMS without systemic etiology. In GPA, when scleritis was the first manifestation that led to the diagnosis of the disease, it did not seem to point to a different phenotype.

Our data reinforce the idea of always considering GPA as the etiology in the diagnosis of scleritis as well as considering the possibility of an ocular manifestation of this type at any time during the established disease. REFERENCES: NIL.

Acknowledgements: NIL.

Disclosure of Interests: Rodrigo da Rocha Jorge: None declared, Alisson Pugliesi Abbvie, Janssen, Lilly, UCB, Pfizer, Boehringer, Astra Zeneca., Boehringer, UCB, Vitor de Castro Grotti: None declared, Regis Suwa Marques: None declared, Maria Fernanda Zacarin: None declared, Zoraida Sachetto: None declared