Mutations Prevalent among Rifampin- and Isoniazid-Resistant
            <i>Mycobacterium tuberculosis</i>
            Isolates from a Hospital in Vietnam

Caws, Maxine; Phan, Minh-Duy; Tho, Dau Quang; Lan, Nguyễn Thị Ngọc; Hoa, Dai Viet; Farrar, Jeremy

doi:10.1128/jcm.00330-06

Cited by 93 publications

(78 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…32 The most common missense mutations associated were located at codons 531 and 526. 8,33,34 However, some studies have also reported other uncommon mutations inside and outside of the "hot-spot" region that were regularly or even systematically missed by standard, World Health Organization-endorsed DST methods. 35,36 The most sensitive limit of detection theoretically possible is three copies per PCR reaction, assuming a Poisson distribution.…”

Section: Discussionmentioning

confidence: 99%

“…[3][4][5][6] Rifampicin (R), resistance is mostly (96%) due to mutations in an 81-(base pair) bp "hot-spot" region of the rpoB gene that encodes the β-subunit of RNA polymerase, especially in codons 531 (43-56%) and 526 (8-31%). [7][8][9][10] Several molecular methods are available for detection of drug resistance mutations, including denaturing gradient gel electrophoresis, conformation-sensitive gel electrophoresis, temperature gradient capillary electrophoresis, denaturing highperformance liquid chromatography, high-density oligonucleotide arrays, and high-resolution melting analysis. [11][12][13][14][15][16][17] These methods vary in sensitivity and are either labor intensive, require sophisticated equipment to perform analyses, or present ambiguity in interpretation.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Rapid Detection of Mycobacterium tuberculosis Strains Resistant to Isoniazid and/or Rifampicin: Standardization of Multiplex Polymerase Chain Reaction Analysis

Collantes¹,

Solari

Rigouts

2016

The American Society of Tropical Medicine and Hygiene

View full text Add to dashboard Cite

Abstract. Drug susceptibility testing using molecular techniques can enhance the identification of drug-resistant Mycobacterium tuberculosis. Two multiplex real-time polymerase chain reaction (qPCR) assays were developed to detect the most common resistance-associated mutations to isoniazid (katGS315T, inhA-15C!T), and rifampicin (rpoBH526Y and rpoBS531L). To assess the species specificity of the qPCR, we selected 31 nontuberculous mycobacteria (NTM) reference strains belonging to 17 species from the public collection of mycobacterial cultures (BCCM/ITM). Additionally, we tested 17 isoniazid and/or rifampicin-resistant strains with other mutations in the target genes to assess mutation specificity. The limit of detection for all the targeted mutations was 20 bacilli/reaction. Multiplex 1 showed 90%, 95%, and 100% efficiency for wild type (WT), Mut katGS315T, and Mut rpoBS531L, respectively; whereas Multiplex 2 showed 97%, 94%, and 90% efficiency for WT, Mut inhA-15, and Mut rpoBH526Y, respectively. Three of 17 strains that presented other mutations in the target genes were identified as rifampicin resistant and only 3/31 NTM showed a similar melting temperature to rpoBL531 and/or katGT315 mutants. Thus, our proposed cascade of specific tuberculosis detection followed by drug resistance testing showed sensitivities for katGS315T, rpoBS531L, rpoBH526Y, and inhA-15 detection of 100%, 100%, 100%, and 96%, respectively; and specificities of 98%, 95%, 100%, and 100, respectively.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Rapid Detection of Mycobacterium tuberculosis Strains Resistant to Isoniazid and/or Rifampicin: Standardization of Multiplex Polymerase Chain Reaction Analysis

Collantes¹,

Solari

Rigouts

2016

The American Society of Tropical Medicine and Hygiene

View full text Add to dashboard Cite

show abstract

“…A test screening for katG_315 mutations is likely to be of the most use in regions with a high prevalence of this mutation, such as China, Russia, the former Soviet states, Vietnam, and Peru (3,5). In Europe, a higher prevalence of inhA gene mutations indicates that a multiplex PCR or hybridization approach is warranted (2,4,19).…”

Section: Discussionmentioning

confidence: 99%

“…Previous sequencing data on isoniazid-resistant isolates from Vietnam indicated that around 80% of isoniazid-resistant isolates could be detected through katG_315 analysis, with katG_S315T being by far the most prevalent mutation (71%) (3). A restriction enzyme test specific for digestion of the CMGCKG site, found at wild-type katG_315, was therefore developed.…”

mentioning

confidence: 99%

PCR-Restriction Fragment Length Polymorphism for Rapid, Low-Cost Identification of Isoniazid-Resistant Mycobacterium tuberculosis

et al. 2007

Self Cite

View full text Add to dashboard Cite

PCR-restriction fragment length poymorphism (PCR-RFLP) is a simple, robust technique for the rapid identification of isoniazid-resistant Mycobacterium tuberculosis. One hundred consecutive isolates from aVietnamese tuberculosis hospital were tested by MspA1I PCR-RFLP for the detection of isoniazid-resistant katG_315 mutants. The test had a sensitivity of 80% and a specificity of 100% against conventional phenotypic drug susceptibility testing. The positive and negative predictive values were 1 and 0.86, respectively. None of the discrepant isolates had mutant katG_315 codons by sequencing. The test is cheap (less than $1.50 per test), specific, and suitable for the rapid identification of isoniazid resistance in regions with a high prevalence of katG_315 mutants among isoniazid-resistant M. tuberculosis isolates.Tuberculosis (TB) control is threatened by increasing resistance to first-line antituberculous agents. The WHO estimates that in the year 2004, 4.3% of new TB cases globally were multidrug-resistant TB (MDR-TB) (29), defined as resistance to at least isoniazid and rifampin. Treatment regimens for MDR-TB are more complex, less potent, more toxic, and more expensive than first-line regimens, resulting in poorer tolerability and adherence and higher morbidity and mortality rates. Early identification of drug-resistant and particularly MDR strains is routine in developed low-prevalence countries, but the methods are currently unavailable to and too costly for resource-poor nations, where the burden of disease is greatest. Early identification of MDR-TB is crucial in order to permit the timely administration of appropriate drug regimens and could potentially improve the efficacy of MDR treatment schemes, such as directly observed treatment, short course-plus.Isoniazid is a prodrug that is activated through cleavage by catalase peroxidase, the product of the katG gene. The active drug has a complex mode of action, which remains to be fully elucidated but principally targets mycolic acid biosynthesis pathways. Upregulation of the inhA gene product, an enoyl-ACP reductase, can overwhelm the impact of isoniazid.Resistance to isoniazid is achieved through mutations in the katG gene, predominantly at codon 315, and in the inhA promoter for the majority of isolates. Mutations in other genes, such as ahpC and ndh, have been implicated in isoniazid resistance, but their roles are not yet proven. A role for kasA gene mutation in isoniazid resistance has recently been discredited (7). Many isolates are isoniazid resistant without any mutations in known target genes, and the mechanism of resistance for these isolates remains obscure.Phenotypic sensitivity testing of Mycobacterium tuberculosis is time-consuming, requiring 2 to 4 weeks from primary specimen in settings with rapid liquid culture systems, such as BACTEC MGIT 960, and 6 to 8 weeks in settings with solidmedium culture (14).Several approaches to the rapid identification of isoniazid resistance have been reported in the literature, including realtime PCR (22), s...

show abstract

“…4,5 Beberapa penelitian menyatakan lebih dari 90% penderita TB yang resisten rifampisin, juga mengalami resistensi terhadap isoniazid, sehingga resistensi terhadap rifampisin merupakan penanda pengganti (surrogate marker) yang mewakili suatu MDR-TB. [6][7][8][9] Rifampisin bekerja dengan berikatan terhadap subunit-β ribonucleic acid (RNA) polimerase yang dikode oleh gen rpoB, suatu komponen penting dalam proses transkripsi. Terhambatnya transkripsi RNA ini menyebabkan terhambatnya sintesis protein.…”

Section: 2unclassified

Validitas Metode Polymerase Chain Reaction GeneXpert MTB/RIF pada Bahan Pemeriksaan Sputum untuk Mendiagnosis Multidrug Resistant Tuberculosis

Sirait¹,

Parwati²,

Dewi³

et al. 2013

mkb

View full text Add to dashboard Cite

AbstrakPengendalian tuberkulosis saat ini terkendala oleh metode diagnostik konvensional yang lambat terutama untuk mendeteksi multidrug resistant tuberculosis (MDR-TB). Deteksi dini MDR-TB sangat penting untuk mencegah penyebaran MDR-TB dan mengurangi angka kematian. Validity of Polymerase Chain Reaction GeneXpert MTB/RIF Method on Sputum Sample Examination to Diagnose Multidrug Resistant Tuberculosis AbstractControl of tuberculosis is hampered by slow conventional diagnostic methods especially for the detection of multidrug resistant tuberculosis (MDR-TB). Early detection of MDR-TB is essential to interrupt MDR-TB transmission and reduce the death rate. The aim of this study was to assess the validity of polymerase chain reaction genexpert MTB/RIF examination, which is a rapid automated molecular examination for the detection of MDR-TB. The study was conducted at the Directly Observed Treatment Short-Course (DOTS) clinic at Dr. Hasan Sadikin General Hospital Bandung. Subjects were patients with suspected MDR-TB. The research sample was sputum which was subjected to microscopic examination, susceptibility test proportion methods in Lowenstein Jensen media and polymerase chain reaction genexpert MTB/RIF examination. During August 2012 until January 2013, 88 subjects were obtained, with most of them were 25-34 years old. There were 54 samples obtained that grew in culture and 34 samples did not grow while 3 samples were other Mycobacteria of tuberculosis. It was also found that 97.5% of rifampin-resistant samples were also resistant to isoniazid. Examination of GeneXpert MTB/RIF showed a sensitivity of 92.3%, specificity of 75% with an accuracy of 88.2%. In conclusion, GeneXpert MTB/RIF examination has high validity for diagnosing MDR-TB against M. tuberculosis gold standard resistance test using the proportion method in Lowenstein Jensen media. The examination is recommended for MDR-TB screening. [MKB. 2013;45(4):234-9]

show abstract

Mutations Prevalent among Rifampin- and Isoniazid-Resistant Mycobacterium tuberculosis Isolates from a Hospital in Vietnam

Cited by 93 publications

References 25 publications

Rapid Detection of Mycobacterium tuberculosis Strains Resistant to Isoniazid and/or Rifampicin: Standardization of Multiplex Polymerase Chain Reaction Analysis

Rapid Detection of Mycobacterium tuberculosis Strains Resistant to Isoniazid and/or Rifampicin: Standardization of Multiplex Polymerase Chain Reaction Analysis

PCR-Restriction Fragment Length Polymorphism for Rapid, Low-Cost Identification of Isoniazid-Resistant Mycobacterium tuberculosis

Validitas Metode Polymerase Chain Reaction GeneXpert MTB/RIF pada Bahan Pemeriksaan Sputum untuk Mendiagnosis Multidrug Resistant Tuberculosis

Contact Info

Product

Resources

About