Bilateral Extensive Syphilitic Punctate Inner Retinitis Triggering Macular Ischemia after Intravitreal Triamcinolone Injections

Purpose: To report a case of extensive syphilitic punctate inner retinitis (SPIR) triggering bilateral macular ischemia after intravitreal triamcinolone injections, and the multimodal retinal imaging findings.Case summary: A 69-year-old male patient with nonproliferative diabetic retinopathy was transferred to our hospital because of bilateral visual deterioration (to counting fingers) after the first intravitreal triamcinolone injection. Fundus examination revealed numerous yellow punctate precipitates in the superficial retinae, retinal arteriolitis, and vitritis. The punctate lesions and surrounding retinal regions showed decreased vascular density on optical coherence tomography angiography, and focal hypofluorescence on fluorescein angiography. The patient was positive for all of the Venereal Disease Research Laboratory test, the fluorescent treponemal antibody-absorption test, and Treponema pallidum hemagglutination; we diagnosed bilateral SPIR. After treatment with aqueous crystalline penicillin solutions (24 million units per day for 14 days), the punctate lesions reduced but arteriolitis progressed to obliterative vasculitis. After 6 months, the bilateral SPIR and vitritis resolved, and the bilateral visual acuity improved to 20/100. However, inner retinal and macular ischemia persisted because of capillary nonperfusion attributable to obliterative vasculitis.Conclusions: Extensive SPIR can develop after an initial intravitreal steroid injection; the inner retinal ischemia and visual loss may persist after treatment because obliterative vasculitis develops. Therefore, patients scheduled for intravitreal steroid injections should be screened for syphilis infection.