Intraocular inflammation in the fellow uninjected eye following intravitreal bevacizumab: a rare complication

PURPOSE To report a rare case of intraocular inflammation (IOI) in the contralateral, uninjected eye following intravitreal (IVT) bevacizumab in a patient with neovascular age-related macular degeneration (nAMD). SETTING An 84-year-old patient with type 2 diabetes mellitus (T2DM), and nAMD in the left eye (LE) was referred to the Ocular Immunovirology Service at Sapienza University of Rome for right eye (RE) uveitis of unknown origin. METHODS A comprehensive ocular examination, including bulbar B-scan ultrasonography in RE, was performed. Laboratory work- up included systemic inflammatory markers, infectious screening, and viral serologies . Aqueous humor was analyzed by PCR. The patient presented with granulomatous anterior uveitis and dense vitritis in the RE. PCR of aqueous humor confirmed HSV-1 infection. The patient achieved full clinical recovery with systemic antiviral therapy. No signs of inflammation recurred in the RE under prophylactic treatment. CONCLUSION IVT bevacizumab, considered more proinflammatory than other anti-VEGF agents due to its full-length antibody structure, may promote immune dysregulation leading to activation of latent HSV, particularly in predisposed individuals such as patients with T2DM. Contralateral IOI following anti-VEGF injection should prompt consideration of a viral etiology and warrant timely PCR testing and antiviral therapy.