Investigation of Cross-Resistance between Rifampin and Rifabutin in Multi-Drug Resistant Mycobacterium tuberculosisLiping Yan, Li Gao, Zhenling Cui, Zhongyi Hu, Junmei Lu, Xiaona Shen and Heping Xiao*
Department of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, People’s Republic of China
- *Corresponding Author:
- Heping Xiao
Department of Tuberculosis
Shanghai Pulmonary Hospital
Tongji University School of Medicine
507 Zhengmin Rd., Shanghai 200433
People’s Republic of China
Fax: 86-21- 65111298
Received date: July 21, 2015; Accepted date: August 17, 2015; Published date: August 21, 2015
Citation: Yan L, Gao L, Cui Z, Hu Z, Lu J, et al. (2015) Investigation of Cross- Resistance between Rifampin and Rifabutin in Multi-Drug Resistant Mycobacterium tuberculosis. Med chem 5:412-414. doi: 10.4172/2161-0444.1000293
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.
Objective: In order to indicate the cross-resistance between rifampin (RFP) and rifabutin (RFB) in multi-drug resistant Mycobacterium tuberculosis (MDR-TB) clinical strains and to provide the laboratory data for using rifabutin in the treatment of MDR-TB.
Methods: The minimal inhibitory concentrations (MICs) of RFB and RFP in 7H10 Middlebrook medium against 99 MDR-TB clinical strains were determined by microplate assays.
Results: Among these 99 isolates, 85 were resistant to rifabutin at concentrations >0.5 μg/ml. The cross-resistance ratio between rifampin and rifabutin was 85.86%. The MICs of RFB were 8-32 times lower than those of RFP (χ²=125.905, p<0.001). The crossresistance ratio increased with the resistance level of RFP. The cross-resistance strains in the lower (the MICs of RFB 2 ~ 4 μg/ml) and the medium groups (the MICs of RFB 8 ~ 16 μg/ml) were 0/9 and 5/9 respectively, while in the high rifampin-resistant group (the MICs of RFB ≥ 32 μg/ml) almost all of the strains but one were cross-resistant (98.8%, 80/81).
Conclusion: RFB has the activities against MDR-TB clinical strains in vitro. The cross-resistance ratio between rifampin and rifabutin increased with the resistance level of RFP. RFB is one of alternativese for the treatment of MDR-TB.