Abstract
Tumor necrosis factor (TNF)-α inhibitors rarely cause optic neuritis as a side effect although the disease associated with ozoralizumab, a novel anti-TNF-α NANOBODY® compound, has not been reported. A 76-year-old female with rheumatoid arthritis, medicated with ozoralizumab, was hospitalized with a two-day history of extending partial visual field loss in the left eye. Campimetry revealed top horizontal hemianopia in the left eye. Swelling and abnormally high intensity of the left optic nerve were observed in magnetic resonance imaging. Visual evoked potential tests revealed delayed latency and reduced amplitude on the left side. She was diagnosed with ozoralizumab-associated isolated optic neuritis and cured with two courses of high-dose intravenous methylprednisolone, followed by oral prednisolone. Ozoralizumab may be associated with optic neuritis although early diagnosis and immunotherapy possibly achieve a good outcome.