In:
Antimicrobial Agents and Chemotherapy, American Society for Microbiology, Vol. 60, No. 4 ( 2016-04), p. 2090-2096
Abstract:
In order to correlate the mutations inside the entire gyrA and gyrB genes with the level of resistance to ofloxacin (OFX) and moxifloxacin (MFX) in isolates of multidrug-resistant Mycobacterium tuberculosis (MDR-TB), a total of 111 isolates were categorized into OFX-susceptible (MIC, ≤2 μg/ml) and low-level (MIC, 4 to 8 μg/ml) and high-level (MIC, ≥16 μg/ml) OFX-resistant isolates and MFX-susceptible (MIC, ≤0.5 μg/ml) and low-level (MIC, 1 to 2 μg/ml) and high-level (MIC, ≥4 μg/ml) MFX-resistant isolates. Resistance-associated mutations inside the gyrA gene were found in 30.2% of OFX-susceptible and 72.5% and 72.2% of low-level and high-level OFX-resistant isolates and in 28.6% of MFX-susceptible and 58.1% and 83.9% of low-level and high-level MFX-resistant isolates. Compared with OFX-susceptible isolates, low-level and high-level OFX-resistant isolates had a significantly higher prevalence of mutations at gyrA codons 88 to 94 (17.0%, 65.0%, and 72.2%, respectively; P 〈 0.001) and a higher prevalence of the gyrB G512R mutation (0.0%, 2.5%, and 16.7%, respectively; P = 0.006). Similarly, compared with MFX-susceptible isolates, low-level and high-level MFX-resistant isolates had a significantly higher prevalence of mutations at gyrA codons 88 to 94 (14.3%, 51.6%, and 80.6%, respectively; P 〈 0.001) as well as a higher prevalence of the gyrB G512R mutation (0.0%, 0.0%, and 12.9%, respectively; P = 0.011). D94G and D94N mutations in gyrA and the G512R mutation in gyrB were correlated with high-level MFX resistance, while the D94A mutation was associated with low-level MFX resistance. The prevalence of mutations at gyrA codons 88 to 94 and the gyrB G512R mutation were higher among fluoroquinolone (FQ)-susceptible East Asian (Beijing) and Indo-Oceanic strains than they were among Euro-American strains, implying that molecular techniques to detect FQ resistance may be less specific in areas with a high prevalence of East Asian (Beijing) and Indo-Oceanic strains.
Type of Medium:
Online Resource
ISSN:
0066-4804
,
1098-6596
DOI:
10.1128/AAC.01049-15
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2016
detail.hit.zdb_id:
1496156-8
SSG:
12
SSG:
15,3
