Acute Endophthalmitis After Intravitreal Injection and Preventive Effect of Preoperative Topical Antibiotics

Abstract

To evaluate the incidence, causative organism, clinical features, and visual outcome of acute endophthalmitis following intravitreal injection and to report the clinical outcome of patients receiving preinjection antibiotics for the prevention of endophthalmitis. For all intravitreal triamcinolone acetonide, bevacizumab, ranibizumab, and C3F8 gas injections performed in our outpatient clinic between June 2008 and November 2012, the number of injections, indications, types of administered drugs, and methods of injection were investigated. A retrospective chart review was performed comparing patients with self-administration of antibiotic eye drops for 3 days before injection (n=8649 injections), and patients those who received no pretreatment with antibiotics (n=8683 injections). Cases of suspected endophthalmitis after intravitreal injection during this period were identified and reviewed retrospectively. The total number of intravitreal injections was 17,332. The incidence of acute endophthalmitis for all intravitreal injections was 0.000% (0/849) for triamcinolone acetonide, 0.022% (2/9,125) for bevacizumab, 0.000% (0/7,061) for ranibizumab, and 0.337% (1/297) for C3F8 gas injections. The overall rate of intravitreal injection-related endophthalmitis with the use of topical antibiotics given 3 days before injection was no less statistically significant compared with that of no antibiotics. Staphylococcus species was confirmed in the bacterial culture of one eye with acute endophthalmitis. After early vitrectomy and intravitreal antibiotic injection, one eye maintained vision, but the other eye developed phthisis. All 3 endophthalmitis patients had not taken prophylactic preinjection topical antibiotics, but the difference in the rates of endophthalmitis between those who received a multiday course of preinjection antibiotics and those who did not was not statistically significant. The rate of endophthalmitis after intravitreal injection using aseptic techniques in the clinical practice setting is similar with or without the use of preinjection antibiotics. Preinjection antibiotic use confers no additional benefit in the treatment of endophthalmitis compared to without preinjection antibiotics.