An Atypical Case of Enterovirus Meningitis Presenting with Unilateral Optic Disc Swelling and Minimal Optical Symptoms

Purpose: To report a case of unilateral disc swelling as the only presentation of enterovirus meningitis in a 43-year-old male who presented with reduction in visual quality. Methods: Vision was 20/20 unaided in both eyes and the only ocular finding was left optic disc edema accompanied by left relative afferent pupillary defect. Visual field examination revealed a generalized reduction in sensitivity, a paracentral scotoma and a superior and inferior arcuate defect. Apart from a marginally elevated white blood cell count, the evaluation for common diseases associated with unilateral disc swelling was negative. A comprehensive neurology and rheumatology assessment,the orbital, brain and cervical spine Magnetic Resonance Imaging (MRI), the chest and abdomen Computed Tomography (CT) and chest radiograph had no findings. However, the cerebrosipinal fluid (CSF) examination indicated the presence of enterovirus RNA. Results: A diagnosis of enterovirus meningitis was established.Patient's general health was not affected and symptoms gradually settled, with no specific anti-enteroviral treatment. Conclusion: Only the CSF analysis provided interesting evidence of the site of the visual dysfunction.