Breaking the mould: An essential need in optic neuritis management

Abstract

Aims/Purpose: To present a clinical case to highlight the importance of ophthalmological examination in the management of optic neuritis.Methods: Case report.Results: A 45‐year‐old woman with Sjögren's syndrome and a family history of MS presents to the emergency department. She complains of decreased vision OD for the past 4 days, with exacerbated‐by‐eye‐movements retroocular pain and migraine‐like headache. BCVA is amaurosis OD and 1 OI, with right RAPD and no colour vision impairment in OI. Except for optic disc oedema with splinter haemorrhages in OD the rest of the ophthalmological examination is normal. RNFL‐OCT reveals thickening in the OD (220 μm/110 μm). Brain CT and laboratory tests, including D‐dimers, are normal. A LP is performed to rule out infectious causes is normal. Neurofilament and ESR are also normal. Brain and spinal MRI show no abnormalities. Due to the severity, methylprednisolone therapy is initiated. One week later, her symptoms are stable, except for headache and retroocular pain improvement. Upon reassessment, despite preserved BCVA and Ishihara in OI, an increase in RNFL thickening is noted in OI (120 μm), with partial arcuate defect in visual field. Anti‐MOG, AQP4 and a panel of autoantibodies including anti‐Ro and anti‐La, are still pending. Considering the bilateral involvement, plasma exchange therapy is initiated. 14 days after, BCVA OU has improved to 1, and the visual field and Ishihara test have normalized. RNFL thickening is still observed OU (161/120 μm) and there is persistent optic disc edema OD. Anti‐MOG are positive, AQP4‐Ab are negative, and both negative in CSF.Conclusions: The coexistence of other autoimmune diseases, can lead to attributing the ON to that disease rather than considering the neuroinflammatory aetiology, leading to delayed diagnosis. The detection of subclinical bilateral involvement was crucial in escalating the therapeutic regimen. Seropositivity is the confirmatory diagnostic marker, but in many centres, it may be difficult to obtain reliable biomarker data.