Detection of Isoniazid and Rifampicin Resistance by Sequencing of katG, inhA, and rpoB Genes in Korea.
10.3343/kjlm.2009.29.5.455
- Author:
Eun Hae CHO
1
;
Hye Kyung BAE
;
Seong Ki KANG
;
Eun Hee LEE
Author Information
1. Greencross Reference Laboratory, Yongin, Korea. ehcho@mail.gcrl.co.kr
- Publication Type:Original Article
- Keywords:
Mycobacterium tuberculosis;
inhA;
katG;
rpoB
- MeSH:
Antitubercular Agents/*pharmacology;
Bacterial Proteins/*genetics;
Catalase/*genetics;
Drug Resistance, Multiple, Bacterial;
Genotype;
Humans;
Isoniazid/*pharmacology;
Mutation;
Mycobacterium tuberculosis/*genetics/isolation & purification;
Oxidoreductases/*genetics;
Republic of Korea;
Rifampin/*pharmacology;
Sensitivity and Specificity;
Sequence Analysis, DNA/*methods
- From:The Korean Journal of Laboratory Medicine
2009;29(5):455-460
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND: In Korea, tuberculosis is resistant to isoniazid (INH) and/or rifampicin (RIF) in more than 10% of cases. To prevent the spread of resistant Mycobacterium tuberculosis strains, it is crucial to develop more rapid resistance detection methods. METHODS: To determine the feasibility of using direct sequencing for detecting INH- and RIF-resistant strains, the katG gene, the regulatory region of the inhA gene, and the 81-bp hot-spot region of the rpoB gene from 95 culture isolates and 46 respiratory specimens were sequenced. Total 141 culture isolates were classified by conventional drug susceptibility testing (DST) as INH(R)/RIF(R) (N=30), INH(R)/RIF(S) (N=23), INH(S)/RIF(R) (N=15), and INH(S)/RIF(S) (N=73). RESULTS: Compared with phenotypic DST, the overall sensitivity and specificity of sequencing were 83.0% (44/53) and 96.6% (85/88), respectively, for INH resistance, and 93.3% (42/45) and 100% (96/96), respectively, for RIF resistance. The rates were similar between culture isolates and respiratory specimens. Interestingly, three specimens with inhA -15C>T mutation were susceptible to INH by conventional DST. CONCLUSIONS: Detection of mutations in the katG codon 315, the inhA regulatory region, and the hot-spot region of rpoB would be useful for rapid detection of INH and RIF resistance in Korea.
