Impact of topical moxifloxacin prophylaxis and povidone iodine on conjunctival bacterial flora in patients receiving intravitreal injections in a tertiary healthcare center in India

PURPOSE: To assess the efficacy of 3 days of topical moxifloxacin in combination with povidone–iodine (PVI) versus moxifloxacin/PVI alone in eliminating conjunctival bacterial flora in patients scheduled to undergo intravitreal injections (IVI). PATIENTS AND METHODS: A prospective randomized comparative study in which 120 patients scheduled to undergo IVI at a tertiary care hospital in New Delhi were selected. Study patients were randomized into two groups. Both the groups received self-administration of moxifloxacin for 3 days prior to injection, except in Group B where it was preceded by PVI. Cultures were obtained at different time intervals, such as in Group A before and after applying moxifloxacin (for 3 days) and once again after applying PVI just before the procedure in the operating room, whereas in Group B first two samples were taken before and after applying PVI and the last sample was taken on the day of the procedure after 3 days of moxifloxacin application. RESULTS: A statistical significance was seen between moxifloxacin prophylaxis and resistant coagulase-negative Staphylococcus (CoNS) (P = 0.0001), which implies that frequent use of antibiotic prophylaxis will ultimately lead to the formation of resistant organisms in the conjunctival flora, especially when repeated IVI are given. CONCLUSION: We could not establish any additional benefits of topical moxifloxacin prophylaxis with regard to a reduction in conjunctival flora when compared with PVI 5%. PVI can be used as an efficient monotherapy in patients undergoing repeated IVI.