Optic neuritis caused by the re-emerging great masquerader.

A 49-year-old Caucasian woman presented with subacute headache and right eye pain associated with scotoma, blurred vision and photophobia. MRI was suggestive of optic neuritis of the right optic nerve and she was treated with steroids. Due to persistent symptoms, a lumbar puncture was performed and cerebrospinal fluid analysis was positive for venereal disease research laboratory and rapid plasma reagin titres. On further history, she recalled experiencing an illness associated with diffuse rash, likely secondary syphilis, 1-2 months prior. She tested negative for HIV. She was treated with intravenous penicillin for 2 weeks following which she experienced improvement in symptoms. © BMJ Publishing Group Limited 2018. No commercial re-use. See rights and permissions. Published by BMJ.