[Atypical presentation of ocular syphilis]

We report the case of a 55-year-old man who presented with a sudden decrease in visual acuity in the left eye, revealing ocular syphilis associated with asymptomatic neurosyphilis. Ophthalmological examination showed mild anterior uveitis of the left eye associated with focal peripheral retinitis displaying a ground-glass appearance, multiple creamy-white superficial retinal precipitates, and obliterative retinal arteritis. Multimodal imaging, particularly optical coherence tomography (OCT), demonstrated full-thickness retinal involvement with retinal layer disorganization, retrohyaloid inflammatory deposits, and hyperreflective preretinal inflammatory condensations. The infectious workup revealed positive syphilis serology (TPHA and VDRL), while HIV serology was negative. An anterior chamber paracentesis excluded other infectious causes. Cerebrospinal fluid analysis confirmed asymptomatic neurosyphilis in the absence of neurological symptoms and with a normal brain magnetic resonance imaging (MRI) scan. Treatment with intravenous penicillin G (24 million units per day for 14 days), combined with corticosteroid therapy, resulted in a favorable outcome, with regression of inflammatory signs and clinical improvement. This case illustrates an unusual presentation of ocular syphilis characterized by ground-glass retinitis associated with retinal vasculitis and superficial retinal precipitates. It highlights the value of multimodal imaging, particularly OCT, in facilitating early diagnosis and emphasizes the importance of systematically investigating neurosyphilis, even in the absence of neurological manifestations.