Vogt-Koyanagi-Harada (VKH) Syndrome Mimicking Bilateral Optic Neuritis

INTRODUCTION: Vogt-Koyanagi-Harada (VKH) syndrome is an idiopathic immune-related disorder that affects multiple organ systems, particularly targeting melanocytes in the uvea, ear, and meninges. It can sometimes present as subacute vision loss and or headache without other systemic features mimicking optic neuritis or Idiopathic intracranial hypertension, leading to an initial misdiagnosis. CASE REPORT: A 36-year-old male presented with an acute onset and progressive diminution of vision in both eyes for 5 days. Fundus examination revealed papillitis. Brain MRI and CSF examination were normal. Serum NMO and MOG were negative. Considering bilateral optic neuritis, he was started on intravenous methylprednisolone therapy, following which his vision showed initial improvement, followed by deterioration after 3 days. The MRI was reviewed again and showed a subtle FLAIR hyperintensity just lateral to the optic nerve entry in the posterior pole, suggestive of choroidal thickening. Optical coherence tomography showed bilateral large Neurosensory retinal detachment and intraretinal fluid. Fundus fluorescein angiography showed multifocal pinpoint hyperfluorescent spots due to leakage from the retinal pigment epithelium and dye pooling in the subretinal space, suggestive of VKH syndrome. Visual acuity improved after 3 cycles of plasma exchange to 6/6 in the right eye and 6/12 in the left eye. CONCLUSION: VKH should be considered in the differential diagnosis of any patient presenting with a history and examination suggestive of bilateral seronegative optic neuritis, even in the absence of characteristic extraocular manifestations of the disease.