A pilot study on comparative analysis of minimum inhibitory concentration and mutant prevention concentration of conjunctival bacterial isolates against fluoroquinolones

The aim of this study was to compare the Minimum Inhibitory Concentration (MIC) and Mutant Prevention Concentration (MPC) of fluoroquinolones, including ciprofloxacin, moxifloxacin, and gatifloxacin, against and coagulase-negative Staphylococci (CONS) isolated from conjunctival swabs. 25 isolates of spp., obtained from conjunctival swabs submitted to the Department of Microbiology, Vision Research Foundation, Sankara Nethralaya, were included in this study. The identification and confirmation of spp. were performed using standard microbiological techniques. The MIC and MPC were determined using the agar dilution method, following protocols from previous studies. The MIC, MIC, MPC, and MPC values for the above three fluoroquinolones were calculated and analysed. Out of all 25 isolates, 20 were CONS and 5 were . In our study, gatifloxacin had least MIC and MPC values when compared to ciprofloxacin and moxifloxacin. of gatifloxacin had lower MPCand MPC values in comparison to ciprofloxacin and moxifloxacin. Our study shows that Gatifloxacin had least MIC and MPC values when compared to ciprofloxacin and moxifloxacin. Besides, MPC of ciprofloxacin, moxifloxacin and gatifloxacin showed wider range of distribution than the MIC. Gatifloxacin demonstrated effective inhibition of resistant mutant strains at lower concentrations compared to ciprofloxacin and moxifloxacin. Additionally, future studies with a larger number of isolates, incorporating pharmacokinetic and pharmacodynamic parameters, will provide essential information on therapeutic outcomes and resistance prevention.