Invitro antibacterial activity of imidazole and triazole-based antimicrobials against Carbapenem Resistant Enterobacteriaceae

Abstract

Introduction The frequency of serious bacterial infections has increased due to the high prevalence of HIV infection, contributing to the increasing rates of multi-drug organisms which include carbapenem-resistant Enterobacteriaceae (CRE). This trend has become a serious challenge to the health care system of South Africa, resulting in the higher use of immunosuppressive and cytotoxic drugs to treat serious bacterial infections. Optimal treatment for infections caused by CRE is yet unknown. The benefits of imidazole and triazole antimicrobials have become very topical due their diverse spectrum of pharmacological properties, but its efficacy against bacterial infections has not been tested in the South African context. Aim The primary aim of this study was to determine the antibacterial effects of selected imidazole and triazole-based antimicrobials against Carbapenem-Resistant Enterobacteriaceae. Methodology Different concentrations of test drugs (ketoconazole, metronidazole and fluconazole) were used to prepare sensitivity disks and four pathogenic strains of Carbapenem Resistant Enterobacteriaceae (K. pneumonia, E. coli, S. marcescens and C. freundii) obtained from Lancet Laboratory in Durban were used to determine the antibacterial activity of the selected test drugs, using Disk Diffusion, Modified Agar Diffusion and Minimum Inhibition Concentration (MIC) method, described by Bauer et al. 1966. Results Antimicrobial Susceptibility Testing revealed that, test drugs selected for this study have no inhibition activity against CRE test organisms and biochemical tests also showed that imidazole and triazoles antimicrobials have no adverse effects on the CRE organisms. Conclusion Although the results obtained in this study indicated no activity of against CRE, laboratory studies are still necessary in modification of the imidazole and triazoles to synthesize derived drugs to confirm and optimize the antibacterial potency of these compounds.