PO:36:242 | Bilateral central retinal artery occlusion as the first manifestation of eosinophilic granulomatosis with polyangiitis during benralizumab therapy

Benedetta Fazzi¹, Elena Treppo¹, Lucia Finocchio², Maria Pillon¹, Luca Quartuccio¹ | ¹Clinica di Reumatologia, Dipartimento di Medicina, Presidio Ospedaliero Universitario Santa Maria della Misericordia, Udine; ²SOC Oculistica, Presidio Ospedaliero Universitario Santa Maria della Misericordia, ASUFC, Udine, Italy

Background. Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare systemic vasculitis characterized by an initial prodromal phase with eosinophil-driven manifestations such as asthma, nasal polyposis, and rhinitis, followed by an antineutrophil cytoplasmic antibody (ANCA)-associated vasculitic phase. Ocular involvement is possible but uncommon (approximately 15% of cases), and central retinal artery occlusion (CRAO) represents an exceedingly rare event. Although benralizumab, a monoclonal antibody targeting the IL-5 receptor, has proven effective in managing eosinophilic manifestations such as asthma and nasal polyposis, its ability to prevent vasculitic damage remains uncertain. We report a case of EGPA complicated by bilateral CRAO occurring during benralizumab therapy.

Case report. A 61-year-old man with a history of adult-onset chronic rhinosinusitis and severe asthma, treated with benralizumab since 2022, presented to the emergency department in June 2024 with sudden bilateral blindness preceded by transient amaurosis episodes, without systemic symptoms or ocular pain. Ophthalmologic examination revealed markedly reduced visual acuity in both eyes (hand motion only) and a relative afferent pupillary defect. Fundus examination showed pale optic discs with central cherry-red spots. Optical coherence tomography (OCT) demonstrated inner retinal layer edema and hyperreflectivity (Figure 1a–c), while fluorescein angiography confirmed delayed retinal arteriolar filling (Figure 1d), findings consistent with CRAO. Laboratory tests revealed elevated inflammatory markers and high-titer myeloperoxidase (MPO)-ANCA positivity (134 IU/mL; positive >3 IU/mL) in the absence of peripheral eosinophilia, likely due to benralizumab therapy. Based on clinical and serological findings, a diagnosis of EGPA was established. High-dose corticosteroids and combined rituximab–cyclophosphamide therapy were initiated according to KDIGO and PEXIVAS recommendations. After an initial improvement, disease relapse occurred with increased MPO-ANCA levels, requiring steroid escalation and two additional cyclophosphamide infusions (cumulative dose: 4 g). Within six months, inflammatory markers and antibody titers normalized; however, visual loss persisted with only partial recovery (finger counting at 1 meter OD, 2/10 OS). Maintenance therapy with rituximab 500 mg every six months was started. Conclusions. This is the first reported case of EGPA complicated by bilateral CRAO occurring during benralizumab treatment. Suppression of eosinophilia did not prevent the development of a severe ANCA-mediated complication, suggesting distinct pathogenic pathways for eosinophilic and vasculitic damage. This case highlights the limitations of IL-5R inhibition in preventing systemic vasculitis and underscores the importance of early and aggressive immunosuppression to avoid irreversible outcomes.