PURPOSE: To evaluate alterations of the conjunctival flora after the use of 0.3% ciprofloxacin and gatifloxacin in the prophylaxis of patients undergoing cataract surgery. METHODS: 40 patients undergoing cataract surgery were distributed into two groups according to the use of antibiotic eye drops: Group A: 0.3% ciprofloxacin and Group B: 0.3% gatifloxacin. Both groups used antibiotic eye drops 1 hour before surgery and 14 days after surgery. Conjunctival material was collected at 5 time points: 1 hour before surgery, without any topical medication (t0); immediately before the application of povidone-iodine (PVPI) (t1), before the beginning of surgery, after povidone-iodine (t2), 14 days (t3) and 28 days after surgery (t4). RESULTS: Preoperative antibiotics reduced the positivity of the cultures before the use of PVPI in both groups, although in Group A this reduction was not significant (Group A - p=0.07 and Group B - p=0.04). The number of positive cultures was reduced in all groups after the use of povidone-iodine and on the 14th postoperative day (p<0.05). In t4 there was a reduction in the frequency of coagulase-negative Staphylococcus in Group A compared with Group B (p<0.05); the susceptibility to ciprofloxacin was also reduced in all groups, when compared with t0. CONCLUSIONS: Gatifloxacin eye drops applied one hour before surgery significantly reduced the number of positive conjunctival cultures. Both antibiotics reduced the conjunctival flora when administered in the postoperative period.
Conjunctiva; Antibiotic prophylaxis; Ciprofloxacin; Povidone-iodine; Drug resistance, microbial; Cataract extraction; Ophthalmic solutions; Endophthalmitis
