Lessons Learnt From 25 Years of Endophthalmitis: Causes, Microbiology and Visual Outcome Trends

BACKGROUND: We aimed to study the trends in microbiology, precipitating causes and outcomes of endophthalmitis in Victoria, Australia, over a 25-year period. To the best of our knowledge, this is the longest study of endophthalmitis in Australia. METHODS: We conducted a prospective study of all endophthalmitis cases to the Royal Victorian Eye and Ear Hospital, a state-wide tertiary referral centre for ocular conditions, thereby capturing nearly all state-wide endophthalmitis cases. All patients presenting with endophthalmitis were included. Demographic data, examination findings, microbiology, management and outcomes were collected. RESULTS: A total of 1423 eyes from 1408 patients were included. The mean (SD) age was 71.35 (16.12). The median presenting best-corrected visual acuity was hand movements. Cataract surgery formed the plurality of annual cases until 2009; intravitreal injections exceeded following. The rate of endophthalmitis secondary to cataract surgery decreased from 0.29%-0.02% over the 25-year period, with a significant decrease following the introduction of prophylactic cefazolin; however, the rate of endophthalmitis secondary to intravitreal injections remained relatively stable (0.01%-0.04%). 63.03% were culture-positive; the plurality grew gram-positive bacteria (42.94%). Visual outcomes were biphasic; 44.99% had a final BCVA of less than 6/60 (including enucleation/evisceration), while 30.6% reached 6/12 or better. Poor visual outcomes were associated with corneal infection; cataract surgery and intravitreal injections were associated with better outcomes. CONCLUSIONS: This study demonstrated declining rates of endophthalmitis secondary to cataract surgery and stable rates of endophthalmitis secondary to intravitreal injections. Visual outcomes were bimodal; while many do very poorly, some have good visual recovery.