Incidence of exogenous endophthalmitis following intravitreal injections: Are we beating international standards?

Abstract

 

Purpose

 

Intravitreal injections have been dramatically increasing over the past decade with the development of newer pharmacological agents. Unfortunately patients often require multiple injections which increases the risk of developing rare sight threatening complications including exogenous endophthalmitis.<br /> The purpose of this audit was to report the incidence of exogenous endophthalmitis secondary to therapeutic intravitreal injections and compare it to international incidence (table 1).

 

Methods

 

A retrospective review of all microbiology intravitreal aspirates performed at the East Kent Hospital NHS Trust was done from 1^st January 2013 to 31^st July 2014. Data was extracted about patients with endophthalmitis from the ‘Medisoft’ intravitreal injection database, discharge summaries and microbiology request forms.

 

Results

 

During the 19 month study interval, 13,032 intravitreal injections were performed (figure 1). The overall incidence rate of endophthalmitis post intravitreal injection was 0.084% per injection (11 of 13,032 injections), giving an annual incidence of 0.053%. Annual incidence for individual injections was Ranibizumab (0.045%), dexamethasone implants (0.722%) and Aflibercept (0.042%).<br /> In the 11 cases in our series, the endophthalmitis occurred at a median of 3 injections (range 1 -31 injections) and at a median of 4 days (range 3-138 days) post injection. Bacterial cultures were positive in 6 cases (54.5%) and revealed Staphylococcus epidermidis (n=5), and Haemophilus Influenza (n=1). All cases were successfully treated using intravitreal antibiotics with some patients having a pars plana vitrectomy on the same admission (n=2) or delayed (n=3). The mean hospital length of stay for patients was 8 days (range 1-36 days). Mean best corrected visual acuity prior to developing endophthalmitis was logmar 0.71 (range 0.12-1.0) and post was logmar 3.00 (range 1.36-3.00).

 

Conclusions

 

Across our hospital trust, rates of exogenous endophthalmitis post injection are comparable to those found internationally. Further studies are required to determine the best prophylactic and aseptic techniques to prevent this sight- threatening complication.  

 

Showing rates of exogenous endophthalmitis secondary to intravitreal injection administration in different countries.

 

 

Graph to show each intravitreal injection as a percentage of the total number of injections.