Ocular Inflammation as a Diagnostic Clue to Systemic Autoimmune Disease: A Report of Two Cases

Ocular inflammatory disorders may represent the first manifestation of systemic autoimmune disease or, less commonly, prompt reconsideration of an existing diagnosis. Two cases are reported below in whom ophthalmic findings played a pivotal role in establishing or revising the underlying rheumatological diagnosis. A 29-year-old female presented with Peripheral Ulcerative Keratitis (PUK) complicated by a 3×3 mm corneal perforation with iris prolapse. Detailed systemic evaluation, prompted by severe ocular disease, revealed previously unrecognised Mixed Connective Tissue Disease (MCTD). The patient underwent tectonic penetrating keratoplasty with amniotic membrane transplantation and temporary tarsorrhaphy, along with systemic immunosuppressive therapy, resulting in successful globe preservation and a clear graft with a Best-Corrected Visual Acuity (BCVA) of 6/24 at long-term follow-up. The second patient, a 43-year-old male receiving treatment for Rheumatoid Arthritis (RA), developed recurrent anterior scleritis. Persistent ocular inflammation prompted repeat autoimmune evaluation, which demonstrated Proteinase 3-Anti-Neutrophil Cytoplasmic Antibody (PR3-ANCA) positivity, leading to reclassification of the diagnosis as Granulomatosis with Polyangiitis (GPA). Escalation of systemic immunosuppressive therapy with intravenous cyclophosphamide achieved satisfactory control of ocular inflammation with residual scleral thinning. These cases highlight the crucial role of ophthalmologists in recognising ocular manifestations that may establish a previously undiagnosed systemic autoimmune disease or necessitate re-evaluation of an existing diagnosis. Early multidisciplinary collaboration and timely systemic immunosuppression are essential to optimise both ocular and systemic outcomes.