Simultaneous Application Of Non-Antibiotics With Antibiotics For Enhanced Activity Against Multidrug Resistant Pseudomonas Aeruginosa

Abstract

The treatment of multi drug resistance (MDR) Pseudomonas aeruginosa has raised a major health concern worldwide. However the combine use of antibiotics and non-antibiotic could be beneficial in the treatment and prevention of MDR P. aeruginosa. The current study is therefore an attempt to evaluate the synergistic effect of antibiotics and non-antibiotic against MDR P. aeruginosa. Currently, a total of 62 P. aeruginosa clinical isolates were investigated. Kirby Bauer Disk diffusion method was used to determine the antibiotic susceptibility of the clinical isolates following the Clinical and Laboratory Standards Institute (CLSI) guidelines. The minimum inhibitory concentrations of the antibiotics including polymyxin B, ciprofloxacin and cefotaxime and non-antibiotics i-e., sertraline, loperamide, metformin and diclofenac sodium were determined using broth micro dilution technique. The synergistic effects of these antibiotics and non-antibiotics were further evaluated using checkerboard assay and fractional inhibitory concentration (FIC). Of the 62 clinical isolates, 53 (85.48%) were confirmed MDR. The individual MICs of cefotaxime, polymyxin B and ciprofloxacin were 32 μg/mL, 16 μg/mL and 64 μg/mL respectively. While the individual MIC of sertraline, loperamide, metformin and diclofenac sodium were 64 μg/mL, 32 μg/mL, 16 μg/mL and 64 μg/mL respectively. . Sertraline and loperamide when combined with polymyxin B showed synergistic antibacterial activity with an FIC value of 0.37 and 0.5 respectively. Similarly diclofenac sodium with cefotaxime also showed synergism with an FIC value of 0.25. However the combination of metformin and ciprofloxacin showed no synergistic activity (FIC=1). It was therefore concluded that the tested combinations had significantly lowered MICs values compared to antibiotics and non-antibiotics individually.