Skip to content
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Menu
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Menu
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Publication Details
AFRICAN RESEARCH NEXUS
SHINING A SPOTLIGHT ON AFRICAN RESEARCH
medicine
gyrA mutations and phenotypic susceptibility levels to ofloxacin and moxifloxacin in clinical isolates of Mycobacterium tuberculosis
Journal of Antimicrobial Chemotherapy, Volume 67, No. 5, Article dks033, Year 2012
Notification
URL copied to clipboard!
Description
Objectives: To compare mutations in the quinolone resistance-determining region of the gyrA gene and flanking sequences with the MICs of ofloxacin and moxifloxacin for Mycobacterium tuberculosis. Methods: The presence of mutations in 177 drug-resistant M. tuberculosis isolates was determined by DNA sequencing and the MICs quantified by MGIT 960. Results: Single nucleotide polymorphisms were detected at codons 94 (n = 30), 90 (n = 12), 91 (n = 3), 89 (n = 1), 88 (n = 1) and 80 (n = 1). Four isolates with double mutations D94G plus A90V (n = 2) and D94G plus D94N (n = 2) reflect mixed populations. Agreement between genotypic and phenotypic susceptibility was high (≥97%) for both drugs. Mutant isolates had an MIC 50 of 8.0 mg/L and an MIC 90 of >10 mg/L for ofloxacin compared with an MIC 50 and MIC 90 of 2.0 mg/L for moxifloxacin. Codons 94 and 88 were linked to higher levels of fluoroquinolone resistance compared with codons 90, 91 and 89. The MIC distributions for the wild-type isolates ranged from ≤0.5 to 2.0 mg/L for ofloxacin and from ≤0.125 to 0.25 mg/L for moxifloxacin. However, 96% of the isolates with genetic alterations had MICs ≤2.0 mg/L for moxifloxacin, which is within its achievable serum levels. Conclusions: This study provides quantitative evidence that the addition of moxifloxacin to extensively drug-resistant tuberculosis (XDR-TB) regimens based on a clinical breakpoint of 2.0 mg/L has merit. The use of moxifloxacin in the treatment of multidrug-resistant tuberculosis may prevent the acquisition of additional mutations and development of XDR-TB. © The Author 2012. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.
Authors & Co-Authors
Sirgel, Frederick Adriaan
South Africa, Stellenbosch
Stellenbosch University
Warren, Robin Mark
South Africa, Stellenbosch
Stellenbosch University
Streicher, Elizabeth Maria
South Africa, Stellenbosch
Stellenbosch University
Victor, Thomas Calldo
South Africa, Stellenbosch
Stellenbosch University
Van Helden, Paul D.
South Africa, Stellenbosch
Stellenbosch University
Böttger, Erik Christian
Switzerland, Zurich
Universität Zürich
Statistics
Citations: 114
Authors: 6
Affiliations: 2
Identifiers
Doi:
10.1093/jac/dks033
ISSN:
03057453
e-ISSN:
14602091
Research Areas
Cancer
Genetics And Genomics
Infectious Diseases
Study Approach
Quantitative