Ocular Syphilis in Individuals with and Without HIV: A Single-Center University Hospital Experience

Syphilis is a re-emerging sexually transmitted infection with rising incidence worldwide, often associated with HIV infection. Ocular syphilis represents a severe manifestation that can occur at any disease stage and may result in permanent vision loss if not promptly diagnosed and treated. We conducted a retrospective comparative cohort study of 22 patients with ocular syphilis managed at Istanbul University, Istanbul Faculty of Medicine, between 2019 and 2025. Twelve patients (54.5%) were people living with HIV (PLWH). The majority were male (81.8%), with a mean age of 45.2 years. Visual loss was observed in more than half of the patients and occurred significantly more frequently in PLWH than in HIV-negative individuals (100% vs. 70%; p = 0.046). Vitritis was also significantly more frequent among PLWH (91.7% vs. 40%; p = 0.02), indicating more severe intraocular inflammation. All six cases of neurosyphilis were confined to PLWH (50% vs. 0%; p = 0.004). The most common ocular manifestations were uveitis (90.9%), predominantly panuveitis and posterior uveitis. All patients received intravenous penicillin G or ceftriaxone, and systemic corticosteroids were administered in half of the cases. Clinical improvement was observed in all patients. Our findings highlight that ocular syphilis in PLWH is associated with more severe inflammation and higher neurosyphilis risk, underscoring the importance of routine cerebrospinal fluid examination and neurosyphilis-based treatment strategies in this group.