Twenty years of endophthalmitis: Incidence, aetiology and clinical outcome

Abstract

Purpose: To review the incidence, aetiology and outcomes of endophthalmitis during a 20-year period in a Norwegian university hospital.

Methods: Single-centre retrospective review. Medical records of all patients admitted to Stavanger University Hospital with suspected endophthalmitis between January 1999 and December 2018 were reviewed.

Results: We identified 84 eyes of 81 patients. Postoperative endophthalmitis (PE) was seen in 64 eyes (76%), endogenous endophthalmitis in thirteen eyes (15%), trauma in four eyes (5%) and three eyes (4%) had keratitis-associated endophthalmitis. Administration of intravitreal injections (IVI) was the most common cause (30%), followed by cataract surgery (CS) (21%). Of 40238 IVI, 23 PE cases were identified (incidence, 0.057%; 95% confidence interval [CI] 0.036-0.086%). Of 39697 CS, 12 PE cases were identified (incidence, 0.030%; 95%CI 0.016-0.053%). After introduction of intracameral cefuroxime PE incidence after CS decreased from 0.10% in 1999-2003 to 0.015% in 2004-2018 (p = 0.003). Eighty-four per cent of organisms were Gram-positive. Coagulase-negative staphylococci accounted for 54% of culture-proven cases, and 89% of post-IVI culture-proven cases. Thirty eyes (36%) either regained their previous vision or lost ≤1 Early Treatment Diabetic Retinopathy Study line. One third of endophthalmitis cases had a favourable visual outcome of logMAR 0.2 or better.

Conclusion: PE after IVI occurred in 1 in 1750 procedures, and was the most common cause of PE. The incidence of PE after CS has decreased >sixfold since 2003, to 1 in 6700 surgeries. A high proportion of low-virulence bacterial species may have contributed to the favourable visual outcome.

Keywords: cataract surgery; endophthalmitis; iatrogenic; incidence; intravitreal injections; postoperative; visual outcome.