Bilateral Parainfectious Optic Neuritis in Young Patient.

Parainfectious optic neuritis arises from infectious aetiology either from pathogen direct invasion or after an infectious disease which can be immunologically mediated demyelination of optic nerve or, from inflammation of optic disc vasculature. We report a case of bilateral optic neuritis in a young patient. A 13-year-old boy presented with painless profound vision loss in both eyes preceded by an episode of fever two weeks prior. Visual acuity in both eyes was a perception of light. Fundoscopy showed a bilateral hyperemic swollen disc. Blood investigations were normal except for C-reactive protein and ESR was elevated. CSF analysis was also normal with no growth of micro-organisms. Both CT scans and MRIs of the brain and orbit showed normal findings. The patient was diagnosed to have parainfectious optic neuritis. He was started on intravenous methylprednisolone for five days followed by a tapering dose of oral prednisolone for a total of one month. His final visual acuity improved to 6/6 in both eyes with a normal optic disc appearance.