Ocular syphilis: Clinical characteristics, HIV status, and outcomes in a 10-year case series from Türkiye

Background Ocular syphilis is a rare but potentially sight-threatening manifestation of Treponema pallidum . Despite increased awareness related to the global resurgence of syphilis and its association with HIV, data from Türkiye remain limited. Methods This case series included patients diagnosed with ocular syphilis at two tertiary centers in Türkiye. We evaluated their clinical, ophthalmologic, serologic, CSF, HIV-related data, treatment, and visual outcomes. Results Twenty-four patients (43 affected eyes) were included; 92% were male, with a median age of 46 years (IQR, 31.0–52.8). Ocular involvement was the initial clinical manifestation of syphilis in 92% of patients, and 54% had no systemic symptoms at presentation. Bilateral disease was observed in 19 patients (79%). Among the 43 affected eyes, posterior uveitis and panuveitis were the most common anatomical patterns, each observed in 15 eyes (35%). Fifty-eight percent of patients were people living with HIV (PLWH), half of whom were newly diagnosed at presentation. PLWH were significantly younger than those without HIV (median 37.0 vs 52.0 years; p = 0.012) and were more frequently men who have sex with men (64% vs 0%; p = 0.002). Lumbar puncture revealed at least one cerebrospinal fluid (CSF) abnormality in 71% of individuals; elevated CSF protein levels were more common among PLWH (85% vs 25%; p = 0.017). All individuals received neurosyphilis-equivalent therapy, resulting in significant improvement in visual acuity (median ΔlogMAR −0.56; p < 0.001). Conclusions Ocular syphilis frequently presents without systemic symptoms and is often associated with HIV. In patients presenting with posterior uveitis or panuveitis, routine syphilis and HIV testing is essential for accurate diagnosis and timely management.