Meta-analysis finds topical antibiotic prophylaxis does not reduce endophthalmitis after intravitreal injection

PURPOSE: To compare the incidence of endophthalmitis after intravitreal injection with versus without topical antibiotic prophylaxis. METHODS: We systematically searched PubMed, Embase, and the Cochrane Library from each database's inception through August 2024. The primary outcome measure was the endophthalmitis rates after intravitreal injection, whereas the secondary outcomes included the distribution and quantity of microorganisms and best-corrected visual acuity changes. Study quality was assessed using the Newcastle-Ottawa Scale. For the meta-analysis, pooled summary estimates were calculated using a random-effects model. RESULTS: Eighteen studies (3,138,778 intravitreal injections; 1,426 endophthalmitis cases) showed no significant difference in endophthalmitis incidence between prophylaxis and no-prophylaxis groups (odds ratio 1.85, 95% confidence interval [CI] 0.72‒4.76; P = 0.2). For microbial analysis, we selected 11 studies that demonstrated no significant difference in culture-positive rates between prophylaxis and nonprophylaxis groups (OR, 1.23; 95% CI, [0.53‒2.84]; P = 0.63). Four studies provided best-corrected visual acuity changes from baseline to final follow-up, antibiotic prophylaxis group showed a decrease by 4.5 ETDRS letters compared with the no-prophylaxis group, although this difference was not statistically significant ( P = 0.65). CONCLUSION: Topical antibiotics did not reduce endophthalmitis risk or improve visual outcomes postintravitreal injection. Given potential risks, routine prophylaxis is not recommended.