Ethambutol resistance as determined by broth dilution method correlates better than sequencing results with embB mutations in multidrug-resistant Mycobacterium tuberculosis isolates.
We evaluated the correlation of phenotypic ethambutol (EMB) susceptibility as determined by two drug susceptibility methods with embB mutations in multidrug-resistant (MDR) Mycobacterium tuberculosis strains. The concordance rate for EMB resistance between broth dilution method and sequencing results (83.6%) was significantly higher than between the proportion method and sequencing results (61.7%) (P = 0.004). Of the embB mutants, 75.4% (46/61) possessed a mutation at embB306. Our results demonstrated that ethambutol resistance determined by broth dilution method reveals better correlation with embB mutations than the proportion method in MDR isolates.
Respiratory Diseases Department of Nanlou, Chinese People's Liberation Army General Hospital, Beijing, China.
Zhijian
Z
Zhang
Yufeng
Y
Wang
Yu
Y
Pang
Kai Man
KM
Kam
D000995:Antitubercular Agents / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial; D004977:Ethambutol / Q000494:pharmacology*; D060005:Genotyping Techniques / Q000379:methods; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D020125:Mutation, Missense; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D010430:Pentosyltransferases / Q000235:genetics*; D017422:Sequence Analysis, DNA; D018088:Tuberculosis, Multidrug-Resistant / Q000382:microbiology*
D000995:Antitubercular Agents; D004977:Ethambutol; C540269:EmbB protein, Mycobacterium tuberculosis; D010430:Pentosyltransferases