In vivo antimicrobial activity of 0.6% povidone-iodine eye drops in patients undergoing intravitreal injections: a prospective study

Abstract

To investigate the antimicrobial activity of a preservative-free 0.6% povidone-iodine eye drop as an antiseptic procedure in decreasing the conjunctival bacterial load in eyes scheduled for intravitreal treatment and to compare its efficacy to the untreated fellow eye used as the control group. Prospective cohort analysis in which 208 patients received preservative-free 0.6% povidone-iodine eye drops three times a day for three days before intravitreal injection. Before and after the prophylactic treatment, a conjunctival swab was collected from both the study eye and the untreated contralateral eye, used as control. The swab was inoculated on different culture media and the colony-forming units were counted. Bacteria and fungi were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Treatment with 0.6% povidone-iodine eye drops significantly reduced the conjunctival bacterial load from baseline (p < 0.001 for blood agar and p < 0.001 for chocolate agar) with an eradication rate of 80%. The most commonly isolated pathogen at each time-point and in both groups was coagulase-negative Staphylococci, isolated in 84% of the positive cultures. The study provides evidence about the effectiveness of 0.6% povidone-iodine eye drops treatment in reducing the conjunctival bacterial load in eyes scheduled for intravitreal treatment.

Prophylaxis of Ocular Infection in the Setting of Intraocular Surgery: Implications for Clinical Practice and Risk Management

“…Accordingly, Pinna et al showed that 0.6% PVI eye drop had rapid in vitro antimicrobial activity against common etiologic agents of ocular infection, such as S. epidermidis, S. aureus, and P. aeruginosa [36]. In vivo non-prospective studies reported the effectiveness of 0.6% PVI eye drop treatment in reducing the conjunctival bacterial load [37,38]. According to published results, PVI eye drop at low concentrations (0.6%) is efficacious in preoperative prophylaxis, allowing for the eradication of conjunctival bacteria and ensuring satisfactory ocular tolerability.…”

Efficacy of Three Povidone Iodine Formulations against Cutibacterium acnes Assessed through In Vitro Studies: A Preliminary Study

“…In non-PJI infections, in both in vitro and in vivo evaluations, the 0.6% ophthalmic formulation of PVP-I was more rapidly bactericidal than the 5% formulation on a variety of clinical and non-clinical staphylococci (including S. aureus), gram-negative bacilli (including Pseudomonas aeruginosa and Escherichia coli) and fungi (Candida sp.) [27][28][29]. This difference in efficacy (only present on bacterial strains) is, according to the authors, most likely due to the fact that dilution from 5% to 0.6% increases the amount of free iodine.…”

Antimicrobials and antiseptics: Lowering effect on ocular surface bacterial flora – A systematic review

“…For instance, Ikuno et al (2012), found that PVI 1.25% was not less effective than PVI 5% in reducing OSBF when administered before IVI. Furthermore, PVI 0.66% was demonstrated to reduce significantly the OSBF in eyes undergoing IVI (Reibaldi et al, 2019; Tognetto et al, 2021). Finally, PVI 0.6% may be well tolerated and improve the ocular surface in patients with dry eye after 28 days of treatment, suggesting that its use could be useful when para‐surgical procedures, like IVI, require repeated instillation of antiseptics (Oliverio et al, 2021).…”