Retrobulbar Optic Neuritis Post Typhoid fever: Atypical Case Report

Purpose: Post typhoid autoimmune-mediated simultaneous retrobulbar optic neuritis (RBN) involving both eyes is a rare complication requiring early diagnosis and prompt treatment. Case presentation: We present a case of bilateral RBN in a six-year-old male who came to our department with a chief complaint of sudden onset painless profound loss of vision in both eyes, after an episode of high-grade fever 2 weeks earlier. Perception of light was doubtful in right eye (RE) and vision was hand movement in left eye (LE). On ocular examination, anterior segment and fundoscopy of both eye were normal. Blood investigation was normal except for raised ESR. CT of brain and orbit was normal. MRI of brain and orbit revealed bilateral thickening and restriction of optic nerve suggestive of ON. He was initiated with intravenous methyl-prednisolone for three consecutive days after which tapering doses of oral corticosteroid was given. Results: A rapid and marked improvement in Uncorrected Visual Acuity (UCVA) was observed with UCVA improving to 6/ 12 RE and 6/ 9 LE post 1 month. The pupillary reaction also became normal in both eyes. Moreover, there was a significant reduction in the Widal titre of the patient post 2 weeks of treatment. Discussion: Paediatric ON has rare and unique characteristics, which differentiates it from adult ON. No clinical trials have been performed for paediatric ON, so current clinical practice follows the evidence drawn from the Optic Neuritis Treatment Trial (ONTT). Conclusion: Paediatric ON is uncommon. Despite having clinically severe bilateral vision loss, retrobulbar optic neuritis in children post typhoid fever has excellent response to steroid therapy if early diagnosed and treated. Abbreviations: RBN = Retrobulbar Optic Neuritis, MRI = Magnetic Resonance Imaging, CT = Computerized Tomography, UCVA = Uncorrected Visual Acuity, RE = Right eye, LE = Left eye, ON = Optic neuritis, ONTT = Optic Neuritis Treatment Trial