Conjunctival flora growth in intravitreal injection settings

Abstract

Purpose: To study the conjunctival flora in patients undergoing repeated intravitreal injections. Methods: Prospective observational study. Patients undergoing intravitreal injections were randomized into two groups: 1) preparation with povidone-iodine 5% alone, or 2) preparation with povidone-iodine 5% with Maxitrol eye drops. Our standard injection technique included topical anesthesia, a solid bladed lid speculum, and commercially prepared topical povidone-iodine 5% applied for 2 minutes. Cultures were obtained from the conjunctival cul-de-sac on routine office visits prior to any preparation and immediately after injection. Results: A total of 110 Eyes of 86 patients were enrolled in the study. Fifty-five were irrigated with povidone-iodine 5% only, and 55 were irrigated with a combination of povidone-iodine 5% and Maxitrol drops. Compared with the povidone-iodine only group, the Maxitrol and povidone-iodine group did not lead to a statistically significant reduction in patients with positive cultures after injection, (p=0.19). The most common organism cultured was coagulase-negative staphylococcus; however, Enterococcus, Pseudomonas, Staphylococcus aureus, and Bacillus were also cultured. Thirtyseven percent of organisms were resistant to 4th generation quinolones. No cases of endophthalmitis were recognized. Of the positive cultures, 33% were resistant to over 4 antibiotics tested. Conclusion: In this routine clinical setting, conjunctival antisepsis was difficult to achieve despite the use of topical povidone-iodine with or without Maxitrol. No infectious complications were recognized.