Case Presentation: A 41-year-old male presented to the ER two days after sudden-onset vision loss in his right eye while driving which he described as a “round black spot the size of a large clock.” This prompted him to stop his car and get out, after which he felt off-balance for 10 minutes. The vision loss in his right eye persisted which urged him to come to the ER. He denied eye pain or previous similar eye symptoms but did report a sudden right ear hearing loss as well, three days prior to the onset of his eye symptoms, which persisted. On review of systems, he had no constitutional symptoms, head/ eye trauma/ foreign body, headache, photophobia, neck stiffness, focal weakness, nausea, or vomiting. Social history was notable for frequent use of methamphetamines and unprotected sexual intercourse with a male partner of undetermined STI status within the past 3 months. Notable exam findings included preserved visual acuity in his left eye and greatly decreased right-sided visual acuity to just light perception with a large central scotoma. His visual fields were intact, and he was noted to have bilateral Argyll-Robertson pupils. The rest of the detailed neurological exam was negative for any other focal deficits. Non-contrast CT head, CT angiogram head/neck, and MRI brain revealed no acute intracranial pathologies. Labs were significant for a reactive RPR with a titer of 1:32. Unable to visualize disc on fundoscopy done in ER. CSF analysis demonstrated lymphocytic pleocytosis, mildly elevated protein, VDRL negative CSF. He was HIV negative, negative for chlamydia and gonorrhea but positive for Hepatitis C. MRI of the orbits was negative for optic neuritis. Ophthalmology evaluation revealed bilateral optic nerve swelling. He was admitted for treatment with IV penicillin for 2 weeks and his vision started to improve. His visual acuity had improved from inability to read the first line of the Snellen Chart to 20/100 on day 7 of treatment, at the time of discharge to Skilled Nursing Facility for completion of IV antibiotics.
Discussion: Ocular syphilis is a rare and early presentation of neurosyphilis that can manifest with a wide spectrum of ocular findings such as anterior or posterior uveitis, panuveitis, interstitial keratitis, optic neuropathy, retinal vasculitis, or retinal detachment. Patients present with varied symptoms such as eye pain, eye pressure, floaters, flashing lights, photophobia, progressively worsening visual acuity or acute painless vision loss. It may occur at any stage of syphilis and precede other signs or symptoms of the disease, making it important to pursue syphilis serology, obtain immediate ophthalmologic evaluation and treat appropriately to prevent permanent blindness. We report the case of an HIV negative 41-year-old male, who had sudden-onset monocular vision loss and large central scotoma which was diagnosed with neurosyphilis manifesting as ocular syphilis, without signs or symptoms of systemic infection including rash, lymphadenopathy, abnormal heart sounds, positive Romberg test, chancres, condyloma lata or gummas.
Conclusions: Ocular syphilis is a manifestation of neurosyphilis that can occur in any stage of syphilis including latent syphilis and may be the first presenting sign of systemic infection that could lead to serious neurologic and cardiovascular complications. Blindness can ensue if ocular syphilis is not identified with a high index of clinical suspicion and treated early with penicillin for the full duration of treatment.