Comparison of Endophthalmitis Rates Between Prefilled Syringes and Standard Vials in Aflibercept Intravitreal...

Area of Science:

• Ophthalmology
• Infectious Diseases
• Drug Delivery Systems

Background:

• Bacterial endophthalmitis is a severe complication following intravitreal injections (IVIs).
• Prefilled syringes aim to minimize contamination during IVI preparation.
• The comparative efficacy of prefilled syringes versus vials in preventing endophthalmitis is not well-established.

Purpose of the Study:

• To compare the incidence of bacterial endophthalmitis after aflibercept intravitreal injections using prefilled syringes versus vials.
• To identify factors associated with poor visual outcomes in cases of bacterial endophthalmitis.

Main Methods:

• Retrospective cohort study of 152,039 aflibercept IVIs across 17 Japanese clinical centers (2015-2022).
• Inclusion criteria: patients aged ≥20 years receiving IVIs for common retinal diseases.
• Bacterial endophthalmitis diagnosis based on clinical signs; incidence rates compared using Fisher's exact test.

Main Results:

• 12 cases of bacterial endophthalmitis were identified (incidence: 0.0046% prefilled syringe vs. 0.0092% vial; p=0.53).
• No statistically significant difference in endophthalmitis incidence between prefilled syringes and vials.
• Poor visual outcomes were linked to Enterococcus faecalis, Streptococcus spp., and patient diabetes.

Conclusions:

• While the incidence of bacterial endophthalmitis was numerically lower with prefilled syringes, the difference was not statistically significant.
• A larger sample size is required to detect a statistically significant difference in endophthalmitis rates.
• Further research is necessary to definitively establish the role of prefilled syringes in reducing endophthalmitis risk.