Purpose: Effect of combination of various antibiotics on Staphylococcus epidermidis biofilm.

Study design: Experimental study.

Methods: The biofilm-producing strains of S. epidermidis were isolated from 100 patients undergoing cataract surgery before instillation of any antibiotic. The strains were subjected to sensitivity test to various antibiotic combinations. The most effective agent was selected and its minimum inhibitory concentration was determined by broth dilution method. The statistics wereperformed using SPSS Version 23 (IBM Corp.) and Chi square test.

Results: A total of 22 biofilm-positive samples were obtained. The combinations of vancomycin with ceftazidime (p < 0.05) followed by moxifloxacin with cefuroxime (p < 0.05) were found to be the most effective. Antibiofilm activity was also shown by other antibiotic combination. The minimum inhibitory concentration of vancomycin and ceftazidime in 11 samples was 2.5 and 2.8 mg/ml, while in the rest of the samples, it was 2.5 and 5.6 mg/ml, respectively. The minimum inhibitory concentration of moxifloxacin and cefuroxime was 0.125 and 2.81 mg/ml, respectively.

Conclusion: In our study, we conclude that antibiotics are effective in eradicating biofilms.