Preoperative topical moxifloxacin 0.5% and povidone-iodine 5.0% versus povidone-iodine 5.0% alone to reduce bacterial colonization in the conjunctival sac

PURPOSE: To assess the effectiveness of adding topical moxifloxacin 0.5% to topical povidone-iodine 5.0% for preoperative reduction of bacterial recovery from the conjunctiva. SETTING: Emek Medical Center, Afula, Israel. METHODS: The study population comprised adult patients scheduled for elective intraocular surgery. Two hours before surgery, patients were randomly assigned to topical therapy with moxifloxacin 0.5% drops (study group) or normal saline drops (control group). Povidone-iodine 5% solution was also instilled in the conjunctival sac in both groups for 3 minutes immediately before surgery. Conjunctival cultures were obtained before prophylactic therapy and just before surgery. The major outcome measures were the rate of bacterial colonization and bacterial type in conjunctival cultures obtained after instillation of povidone-iodine and immediately before surgery. RESULTS: Overall, 464 patients completed the study; there were 237 patients in the study group and 227 patients in the control group. Positive conjunctival cultures were obtained before prophylactic therapy in 91 patients (38%) in the study group and 94 patients (41%) in the control group and just before surgery in 10 patients (4%) and 6 patients (3%), respectively; neither difference was statistically significant. Coagulase-negative Staphylococcus was the most prevalent bacteria and was found equally in both groups. CONCLUSIONS: Treatment with povidone-iodine 5.0% alone was effective in preoperative reduction of conjunctival bacterial colonization. Adding topical moxifloxacin 0.5% to povidone-iodine 5.0% had no significant effect on further reduction in the bacterial colonization rate.