A Red Eye in an Elderly Patient: A Case Report Highlighting the Importance of Urgent Diagnosis.

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides are a distinct group of autoimmune disorders characterized by necrotizing inflammation of small blood vessels. Three distinct clinical entities are described, including eosinophilic granulomatosis with polyangiitis (EGPA), granulomatosis with polyangiitis (GPA), and microscopic polyangiitis (MPA). GPA often presents as a multi-system inflammatory disease frequently involving the sinuses, kidney, and lung tissue. Ophthalmologic involvement has been described in GPA and is highly important to recognize, especially if presenting as the initial symptom of the disease. Prompt diagnosis and treatment are essential, given the significant morbidity and mortality associated with GPA.