The Spectrum of Subretinal Abscess: Insights from a 15-Year Single‑Center Experience.

PURPOSE: To report the clinical outcomes and microbiological spectrum of subretinal abscess (SRA) over a 15-year period at a tertiary eye care center in South India. METHODS: Retrospective review of electronic medical records at a tertiary eye care institute for patients clinically diagnosed with SRA from 2009 to 2024. SRA was classified as tubercular (TB-SRA) and non-tubercular (non-TB SRA) based on clinical and microbiological evidence. RESULTS: Forty-three patients (50 eyes) were included (83.7% male; 16.3% bilateral); 15 patients (34.9%) had TB-SRA and 28 (65.1%) had non-TB SRA. There was no significant difference in presenting visual acuity between TB-SRA vs non-TB SRA (1.82 ± 1.16 vs 2.15 ± 1.20 LogMAR; p = 0.18). Microbiological confirmation was less frequent in TB-SRA vs non-TB SRA (26.7% vs 60.7%; p = 0.03); common pathogens in non-TB SRA included Staphylococcus, Klebsiella, and Aspergillus while Mycobacterium tuberculosis was the most common pathogen overall. Systemic risk factors for non-TB SRA included diabetes, immunosuppression, HIV, and recent COVID-19. All patients with TB-SRA received anti-tubercular therapy with/without corticosteroids, while non‑TB SRA was treated with intravitreal and systemic targeted antimicrobials along with vitrectomy. Despite intravitreal and systemic therapy, visual outcomes remained poor, with no significant difference in final visual acuity between TB-SRA vs non-TB SRA (2.57 ± 1.92 vs 2.76 ± 1.71 LogMAR; p = 0.3) with many eyes progressing to no light perception (37.5% vs 35.3%). CONCLUSION: Non-TB etiology accounted for approximately two-thirds of all SRA and is associated with systemic immunosuppression, while TB-SRA is commonly associated with systemic TB. Microbiological diagnosis remains challenging, and clinical outcomes are often suboptimal.