Case Presentation: A 44 year-old HIV-positive man on HAART with a CD4 count of 340 cells/mm3 and a history of primary syphilis treated with penicillin G benzathine presented to the ophthalmology clinic with five days of right eye redness, lacrimation, blurred vision and floaters. Examination of right eye revealed conjunctival injection and eyelid edema. Visual acuity of the right eye was 20/40 and slit-lamp examination was remarkable for leukocytes, “flare” and infero-nasal posterior synechiae. Ophthalmoscopy revealed leukocytes in the vitreous and superior retinal opacification from 9 o’clock to 3 o’clock extending into the arcade and approaching the macula. Evaluation upon admission revealed a 5-day history of right-sided headache without photophobia or nuchal rigidity, multiple white, painful lingual ulcers, and unremarkable motor and sensory neurological examination. He was started on valganciclovir and IV penicillin G. Laboratory data revealed a WBC count of 7,600 cells/mm3, HIV viral load of 124 copies/ml and RPR titer of 1:16. Blood CMV viral load was less than 50 IU/ml. Serum toxoplasma IgG and IgM, varicella and HSV 1 and 2 IgM by ELISA were all negative. A positive CSF VDRL, mononuclear pleocytosis (30 cells/mm3, 66% lymphocytes, 29% monocytes) and CSF protein level of 65 mg/dL led to a diagnosis of neurosyphilis. CSF analysis was further remarkable for negative VZV, HSV 1 and 2, and CMV DNA PCR. Ocular syphilis was diagnosed after negative CMV, VZV, HSV 1 and 2 and toxoplasma DNA PCR of right aqueous fluid aspirate in conjunction with positive CSF VDRL and findings on slit-lamp biomicroscopy and fundoscopy. Valganciclovir was discontinued and a 2-week course of IV penicillin G was completed. Visual acuity deteriorated to 20/800 on hospital day 4 and improved to 20/20 at 1-month follow-up.

Discussion: Ocular syphilis appears to be witnessing a resurgence, particularly in men who have sex with men. It can also present as the sole manifestation of neurosyphilis, as with this case. Uveitis remains the most common presentation of ocular syphilis with two characteristic patterns. First, superficial small white precipitates and retinal involvement characterized by a mildly opacified appearance distinct from white, necrotizing herpetic retinitis. Alternatively, there may be distinct circular areas of outer retinal and inner choroidal inflammation at the posterior pole referred to as “posterior placoid retinitis”. Although precipitates were notably absent in this case, retinal inflammation similar to the first pattern was observed on ophthalmoscopy. CSF examination is recommended in all cases of ocular syphilis and was performed in this case showing positive VDRL, mononuclear pleocytosis and increased CSF protein, all favoring neurosyphilis. However, blood treponemal serology (FTA-ABS, MHA-TP) was not performed. As with neurosyphilis, ocular syphilis is treated with IV penicillin G for 10-14 days. A four-fold decrease in titer of non-treponemal tests is taken as evidence of response to treatment. Prognosis remains good, with visual improvement within 1 month.

Conclusions: Ocular syphilis in HIV patients is associated with more severe and diffuse inflammation that poses a significant immediate risk to vision. Nevertheless, once promptly diagnosed, it is treatable with a relatively brief course of parenteral penicillin G, making early recognition a priority.