In Vitro Synergism Testing of Three Antimicrobial Agents against Multidrug-Resistant and Extensively Drug-Resistant Mycobacterium tuberculosis by Checkerboard Method
Received Date: Dec 17, 2014 / Accepted Date: Jan 06, 2015 / Published Date: Jan 15, 2015
Abstract
Objective: In view of the national key project for infectious diseases “the retreatment research of tuberculosis”, we determined the in vitro anti-mycobacterial activity of four drugs in the treatment, pasiniazid (Pa), moxifloxacin (Mfx), Rifabutin (Rfb) and rifapentini (Rft) in combination to multidrug-resistant and extensively drug-resistant Mycobacterium tuberculosis.
Method: Three-dimensional checkerboard in Middlebrook 7H9 broth microdilutions was used to detect the fractional inhibitory concentration index (FICI) of anti-tuberculosis drug combination (MfxPa, MfxPaRfb and MfxPaRft) to twenty clinical isolates of Mycobacterium tuberculosis, including ten multidrug-resistant isolates and ten extensively drug-resistant isolates. The test results were interpreted by calculating the FICI to judge the in vitro synergy, with FICI <0. 5 and FICI <0.75 as the basis of two drugs and three drugs have synergy.
Results: The FICI range of MfxPa combination for multidrug-resistant isolates and ten extensively drug-resistant isolates was 0.28-1, only three isolates <0.5, showed synergistic effect. The FICI range of MfxPaRfb combination for ten isolates of multidrug-resistant isolates was from 0.31 to 1.25, two isolates <0.75, showed synergistic effect and for ten isolates of extensively drug-resistant isolates was from 0.53 to 1.25, five isolates <0.75, showed synergistic effect. The FICI range of MfxPaRft combination for ten isolates of multidrug-resistant isolates was from 0.16 to 0.655, all showed synergistic effect and for ten isolates of extensively drug-resistant isolates was from 0.34 to 1.68, five isolates <0.75, showed synergistic effect.
Conclusion: The synergism of MfxPa combination was poor. When a third agent (Rfb or Rft) was added to the combination, the synergistic effect was better. The MfxPaRft combination showed better synergism than MfxPaRfb combination.
Keywords: Multidrug-resistant M. tuberculosis; Extensively drugresistant M. tuberculosis; In vitro synergy; Fractional inhibitory concentration index; Broth microdilution checkerboard
Citation: Yan L, Zhang L, Yang H, Xiao H (2015) In Vitro Synergism Testing Of Three Antimicrobial Agents against Multidrug-Resistant and Extensively Drug- Resistant Mycobacterium Tuberculosis by Checkerboard Method. J Mol Pharm Org Process Res 2: 123. Doi: 10.4172/2329-9053.1000123
Copyright: ©2015 Yan L, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Share This Article
Recommended Conferences
11th International Conference on Complementary & Alternative Medicine
Zurich, SwitzerlandRecommended Journals
Open Access Journals
Article Tools
Article Usage
- Total views: 19349
- [From(publication date): 3-2015 - Dec 03, 2024]
- Breakdown by view type
- HTML page views: 14776
- PDF downloads: 4573