Clinical Relevance of Autoantibodies and Inflammatory Parameters in Non-infectious Scleritis

Potential Biomarkers for Noninfectious Scleritis Identified by Serum and Tear Fluid Proteomics

Purpose

Scleritis is an extremely painful and potentially blinding inflammation of the sclera with unknown pathogenesis and unpredictable course. To gain insight in its disease process and identify biomarker candidates, we performed extensive proteomics in serum and tear fluid.

Design

Prospective multicenter cohort study.

Participants

A total of 121 patients with noninfectious scleritis (of which 39 active cases), 30 healthy controls, and 23 disease controls (uveitis and rheumatoid arthritis) were enrolled in the Netherlands from 2020 to 2022.

Methods

Serum, tear fluid of both eyes, and clinical data were gathered. The level of 368 inflammatory proteins was measured using proximity extension assays. Results were validated in an independent cohort of 15 patients with scleritis, and using addressable laser bead immunoassay, or enzyme-linked immunoassays. In addition, we studied an extended panel of matrix metalloproteinases in tear fluid of necrotizing scleritis with addressable laser bead immunoassay.

Main Outcome Measures

Statistically significant differences in the level of inflammatory proteins between patients with scleritis and control groups.

Results

Proteomics revealed 18 significantly upregulated or downregulated serum proteins in active scleritis cases compared with all control groups in both the discovery cohort and the validation cohort. The most upregulated protein was nuclear migration protein nudC (NudC; P = 0.0032), a protein involved in neurogenesis. The other significant hits included proteins involved in T-cell activation, apoptosis, epithelial barrier maintenance, and angiogenesis. Our tear fluid analysis showed matrix metalloproteinase 9 (MMP9) to be upregulated in the tear fluid of patients with scleral necrosis.

Conclusions

The results of our proteomics analysis suggest a role for neurogenesis, T-cell activation, disruption of epithelial barrier, and angiogenesis in the pathogenesis of scleritis, and highlight MMP9 and NudC as biomarkers with potential clinical relevance.

Funding Disclosures

The authors have no proprietary or commercial interest in any materials discussed in this article.

Inflammatory eye disease for rheumatologists

PURPOSE OF REVIEW

This review provides a framework for understanding inflammatory eye disease diagnosis, differential diagnosis, and management for rheumatologists. Uveitis, scleritis, episcleritis, peripheral ulcerative keratitis, and orbital inflammation are all discussed. The goal is to facilitate the development of approaches to inflammatory eye diseases that will help rheumatologists co-manage these patients with eye care providers specializing in ocular inflammation.

RECENT FINDINGS

In recent years, studies have aimed to advance biologic treatments and define standard-of-care therapy. Inflammatory eye diseases are highly heterogeneous and often rare, which poses significant challenges to their research and the interpretation of existing data. To date, glucocorticoids, mycophenolate, methotrexate, and TNF inhibitors remain the mainstay of treatment options for many of these diseases.

SUMMARY

Patients with inflammatory eye diseases require multidisciplinary care for best outcomes, frequently including rheumatologists. Understanding the differentials, diagnostics, and treatment are essential to preserving vision in these patients. The diverse nature of the disease processes within this field requires focusing on specific disease phenotypes and endotypes in research and clinical practice.

[Diagnostic and Therapeutic Management of Episcleritis and Scleritis]

While episcleritis is a benign disease only affecting the episclera, scleritis is an ocular inflammation with typically severe pain and not rarely affecting adjacent tissue.Scleritis is classified into anterior and posterior forms. Anterior scleritis is further subdivided into diffuse, nodular, necrotizing with inflammation, and necrotizing scleritis without inflammation (scleromalacia perforans). A systemic disease such as rheumatoid arthritis or granulomatosis with polyangiitis is associated with up to 50% of all patients with scleritis or episcleritis, consequently a systemic work-up with blood sampling and imaging as well as collaboration with internists are necessary.Differentiating these two entities is of high importance for planning the treatment: episcleritis has a self-limited course, whereas treatment of scleritis is obligatory to protect patients from irreversible visual loss, organ damage, and furthermore reduce the risk of mortality.Treatment depending of subtype and associated systemic disease may involve non-steroidal anti-inflammatory drugs, corticosteroids, and disease-modifying anti-rheumatic drugs.

Diagnostisches und therapeutisches Management der Episkleritis und Skleritis

Das schmerzhafte „rote Auge“ ist wohl das auffälligste Zeichen einer Augenerkrankung, hinter der milde, aber auch schwere Verläufe stecken können. Die Episkleritis und Skleritis sind hierbei wichtige Differenzialdiagnosen. Die rechtzeitige Diagnose ist nicht nur wichtig für die notwendige Therapie, sondern kann vor einer irreversiblen Visusminderung, einem Augenverlust sowie Organschäden schützen und ggf. sogar das Mortalitätsrisiko senken.