BACKGROUND: Considering the potentials of gatifloxacin and moxifloxacin in the treatment of tuberculosis, the present study was aimed to define resistance to both these drugs. METHODS: Fifty Mycobacterium tuberculosis isolates, consisting of 30 ofloxacin-susceptible and 20 ofloxacin-resistant strains, were tested for their susceptibility to gatifloxacin and moxifloxacin using different susceptibility testing methods, namely the absolute concentration method on Lowenstein-Jensen medium (LJ), the proportion susceptibility testing method (PST) on LJ and 7H11 agar media, and the BACTEC radiometric method. RESULT: The minimal inhibitory concentration (MIC) of gatifloxacin and moxifloxacin was 1 microg/ml by the absolute concentration method on LJ. In the PST method on LJ and 7H11, using a criterion of > or =1% growth as resistant, there was 100% agreement with the absolute concentration method at a concentration of 0.5 microg/ml for gatifloxacin, and 96% agreement with the BACTEC method at a concentration of 0.25 microg/ml. For moxifloxacin, results by the PST method showed 96% agreement with the absolute concentration method on LJ at a concentration of 1 microg/ml and 92% agreement at a concentration of 0.5 microg/ml for both the absolute concentration method on 7H11 and the BACTEC method. CONCLUSIONS: The MICs of gatifloxacin and moxifloxacin were much lower than the MICs of other quinolones like ofloxacin and ciprofloxacin. Additionally, these two drugs have shown a low mean MIC and low concentration as a definition of resistance, which might help in treating the patients with low levels of quinolone resistance.
BACKGROUND: Considering the potentials of gatifloxacin and moxifloxacin in the treatment of tuberculosis, the present study was aimed to define resistance to both these drugs. METHODS: Fifty Mycobacterium tuberculosis isolates, consisting of 30 ofloxacin-susceptible and 20 ofloxacin-resistant strains, were tested for their susceptibility to gatifloxacin and moxifloxacin using different susceptibility testing methods, namely the absolute concentration method on Lowenstein-Jensen medium (LJ), the proportion susceptibility testing method (PST) on LJ and 7H11agar media, and the BACTEC radiometric method. RESULT: The minimal inhibitory concentration (MIC) of gatifloxacin and moxifloxacin was 1 microg/ml by the absolute concentration method on LJ. In the PST method on LJ and 7H11, using a criterion of > or =1% growth as resistant, there was 100% agreement with the absolute concentration method at a concentration of 0.5 microg/ml for gatifloxacin, and 96% agreement with the BACTEC method at a concentration of 0.25 microg/ml. For moxifloxacin, results by the PST method showed 96% agreement with the absolute concentration method on LJ at a concentration of 1 microg/ml and 92% agreement at a concentration of 0.5 microg/ml for both the absolute concentration method on 7H11 and the BACTEC method. CONCLUSIONS: The MICs of gatifloxacin and moxifloxacin were much lower than the MICs of other quinolones like ofloxacin and ciprofloxacin. Additionally, these two drugs have shown a low mean MIC and low concentration as a definition of resistance, which might help in treating the patients with low levels of quinolone resistance.
Authors: Ricky W T Lau; Pak-Leung Ho; Richard Y T Kao; Wing-Wai Yew; Terrence C K Lau; Vincent C C Cheng; Kwok-Yung Yuen; Stephen K W Tsui; Xinchun Chen; Wing-Cheong Yam Journal: Antimicrob Agents Chemother Date: 2010-10-18 Impact factor: 5.191
Authors: Andrea Von Groll; Anandi Martin; Pontus Jureen; Sven Hoffner; Peter Vandamme; Françoise Portaels; Juan Carlos Palomino; Pedro Almeida da Silva Journal: Antimicrob Agents Chemother Date: 2009-08-17 Impact factor: 5.191
Authors: Christoph Lange; Ibrahim Abubakar; Jan-Willem C Alffenaar; Graham Bothamley; Jose A Caminero; Anna Cristina C Carvalho; Kwok-Chiu Chang; Luigi Codecasa; Ana Correia; Valeriu Crudu; Peter Davies; Martin Dedicoat; Francis Drobniewski; Raquel Duarte; Cordula Ehlers; Connie Erkens; Delia Goletti; Gunar Günther; Elmira Ibraim; Beate Kampmann; Liga Kuksa; Wiel de Lange; Frank van Leth; Jan van Lunzen; Alberto Matteelli; Dick Menzies; Ignacio Monedero; Elvira Richter; Sabine Rüsch-Gerdes; Andreas Sandgren; Anna Scardigli; Alena Skrahina; Enrico Tortoli; Grigory Volchenkov; Dirk Wagner; Marieke J van der Werf; Bhanu Williams; Wing-Wai Yew; Jean-Pierre Zellweger; Daniela Maria Cirillo Journal: Eur Respir J Date: 2014-03-23 Impact factor: 16.671