A Rare Case of Neurosyphilis with Ocular Involvement in a Patient with HIV Infection and New Onset Syphilis.

Neurosyphilis (NS) is more frequently seen in patients with human immunodeficiency virus (HIV) infection, especially those not on antiretroviral therapy or with a low CD4 cell count. Ocular syphilis is an unusual and early form of neurosyphilis. Lumbar puncture should be considered in all HIV infected patients who present with neurologic or ocular disease. A 47-year-old homosexual male with HIV-1 infection, on antiretroviral therapy (last CD4 cell count 1022 cells/μL) presented to our emergency department with a five-day history of headache, blurry vision, pain and redness of the left eye. He had unprotected anal sex with a new partner four months before presentation. Based on the fundoscopy findings as well as the cerebrospinal fluid (CSF) analysis on initial evaluation, a repeat serum rapid plasma reagin (RPR) along with microhemagglutination assay for treponema pallidum (MHA-TP) were done due to high suspicion of syphilis, even though an RPR five months prior to this visit was negative. Both RPR and MHA-TP were positive and the patient was treated for neurosyphilis. The patient's symptoms as well as the RPR titers improved significantly thereafter. A high index of suspicion for neurosyphilis should be maintained in HIV-infected patients presenting with ocular symptoms even if they are compliant with retroviral therapy with good CD4 cell counts. Physicians must be mindful of this uncommon presentation and consider a lumbar puncture in any patient with suspicion of neurosyphilis for prompt diagnosis and treatment to avoid further neurological complications.