Discriminatory Ability of Hypervariable Variable Number Tandem Repeat Loci in Population-based Analysis of<i>Mycobacterium tuberculosis</i>Strains, London, UK

Velji, Preya; Nikolayevskyy, Vladyslav; Brown, Timothy J.; Drobniewski, Francis

doi:10.3201/eid1510.090463

Cited by 24 publications

(24 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Loci QUB3232 and QUB11a have been previously found to have a higher mutation rate regarding allelic diversity in M. tuberculosis and were therefore considered hypervariable (27); nevertheless, their use remains controversial as they may contribute to improved discrimination in determined settings (15). Conflicting findings may be due to variations between different lineages (31) or between species; e.g., allelic diversities may differ in M. bovis (18,19). For the additional 16 isolates of different spoligotypes, QUB3232 was also the most discriminatory locus, followed by ETR-A and QUB11a.…”

mentioning

confidence: 41%

Limitations of Spoligotyping and Variable-Number Tandem-Repeat Typing for Molecular Tracing of Mycobacterium bovis in a High-Diversity Setting

et al. 2011

View full text Add to dashboard Cite

show abstract

mentioning

confidence: 41%

Limitations of Spoligotyping and Variable-Number Tandem-Repeat Typing for Molecular Tracing of Mycobacterium bovis in a High-Diversity Setting

et al. 2011

View full text Add to dashboard Cite

show abstract

“…1 and 2. Equally, the number of clusters may be reduced by increasing the number of MIRU-VNTR markers used for analysis or by using further analytical techniques, as has been demonstrated for discriminative analysis of M. tuberculosis (27,28). Pulmonary disease was more common among clustered cases than among unique cases.…”

Section: Discussionmentioning

confidence: 99%

Investigating Transmission of Mycobacterium bovis in the United Kingdom in 2005 to 2008

Mandal¹,

Bradshaw²,

Anderson³

et al. 2011

J Clin Microbiol

Self Cite

View full text Add to dashboard Cite

Due to an increase in bovine tuberculosis in cattle in the United Kingdom, we investigated the characteristics of Mycobacterium bovis infection in humans and assessed whether extensive transmission of M. bovis between humans has occurred. A cross-sectional study linking demographic, clinical, and DNA fingerprinting (using 15-locus mycobacterial interspersed repetitive-unit-variable-number tandem-repeat [MIRU-VNTR] typing) data on cases reported between 2005 and 2008 was undertaken. A total of 129 cases of M. bovis infection in humans were reported over the period, with a decrease in annual incidence from 0.065 to 0.047 cases per 100,000 persons. Most patients were born pre-1960, before widespread pasteurization was introduced (73%), were of white ethnicity (83%), and were born in the United Kingdom (76%). A total of 102 patients (79%) had MIRU-VNTR typing data. A total of 31 of 69 complete MIRU-VNTR profiles formed eight distinct clusters. The overall clustering proportion determined using the n ؊ 1 method was 33%. The largest cluster, comprising 12 cases, was indistinguishable from a previously reported West Midlands outbreak strain cluster and included those cases. This cluster was heterogeneous, having characteristics supporting recent zoonotic and humanto-human transmission as well as reactivation of latent disease. Seven other, smaller clusters identified had demographics supporting recrudescence rather than recent infection. A total of 33 patients had incomplete MIRU-VNTR profiles, of which 11 may have yielded 2 to 6 further small clusters if typed to completion. The incidence of M. bovis in humans in the United Kingdom remains low, and the epidemiology is predominantly that of reactivated disease.

show abstract

“…Crude DNA extracts were isolated from cultures by heating (95°C, 30 min), followed by sonication (20 min). Isolates were genotyped using spoligotyping and variable-number tandem-repeat (VNTR) typing with a standardized panel of 24 loci as described previously (21,32,44,45). The VNTR loci 3232, 3336, 2163A, and 1982 were used, in addition to the standard panel (44).…”

Section: Methodsmentioning

confidence: 99%

Evaluation of Two Molecular Assays for Rapid Detection of Mycobacterium tuberculosis Resistance to Fluoroquinolones in High-Tuberculosis and -Multidrug-Resistance Settings

et al. 2011

View full text Add to dashboard Cite

The Russian Federation is a high-tuberculosis (TB)-burden country with high rates of drug resistance, including multidrug and extensive drug resistance to TB (M/XDRTB). Rapid diagnosis of resistance to fluoroquinolones (FQs) using molecular assays is essential for the implementation of appropriate drug regimens and prevention of the transmission of XDR strains. A total of 51 individual MDRTB strains were tested by pyrosequencing of the quinolone resistance determining region of the gyrA gene and the GenoType MTBDRsl assay (Hain Lifescience, GmbH, Nehren, Germany), and the results were evaluated against those obtained by phenotypic drug susceptibility testing (DST). Mutations were detected in 25 (78.1%) FQ-resistant strains, with the majority of mutations (n ‫؍‬ 19 [73.0%]) found in codon 94 of the gyrA gene; the novel mutation 1457 C3⌻ was found in the gyrB gene. Three mixed allelic variants were detected, which is a well-known phenomenon in areas with high TB and drug-resistant TB rates. The sensitivity and specificity of pyrosequencing (86.2 and 100%, respectively) and MTBDRsl (86.2 and 100%, respectively) were high; however, the results for 5.9% of the analyzed strains were unreadable when MTBDRsl was used. The MTBDRsl and pyrosequencing assays offer a rapid and accurate means for diagnosing resistance to FQs in high-TB-burden areas.Tuberculosis (TB) remains a major threat to public health worldwide and in the developing world in particular, causing almost 2 million deaths annually. The real magnitude of drug resistance is not yet known, although the Indian subcontinent, China, and Russia are believed to account for the majority of cases globally (48).Multidrug-resistant TB (MDRTB), caused by TB bacilli resistant to both isoniazid (INH) and rifampin (RIF), poses difficulties in diagnosis and treatment, with lower survival rates (especially in HIV-infected persons) and the associated high costs of TB control programs. The World Health Organization (WHO) estimates current MDRTB rates in new and previously treated cases globally to be 2.9 and 15.3%, respectively (50).The Russian Federation is a high-TB-burden country with high rates of TB drug resistance, dominated by TB strains of the Beijing family reported to be associated with MDRTB (7, 42). The Samara Oblast (Central Russia) is a hot spot for both TB and HIV epidemics; ca. 20% of new TB cases are MDR, with rates even higher in previously treated cases and in the prison sector (8). Converging TB, drug-resistant TB, and HIV epidemics pose a serious problem for low-and middle-income countries such as Russia where access to second-and third-line drug therapy is limited (2, 8).The rate of extensively drug-resistant TB (XDRTB) (which is caused by MDRTB bacilli with additional resistance to a fluoroquinolone [FQ] and one or more injectable drugs) has been increasing in Russia (36) due to multiple incomplete treatment regimens and poor infection control practice. Cases of XDRTB show a high rate of treatment failure and mortality especially in XDRTB patients with c...

show abstract

Discriminatory Ability of Hypervariable Variable Number Tandem Repeat Loci in Population-based Analysis ofMycobacterium tuberculosisStrains, London, UK

Abstract: Hypervariable loci should be included in standardized panels because they can provide consistent comparable results in multiple settings.

Cited by 24 publications

References 29 publications

Limitations of Spoligotyping and Variable-Number Tandem-Repeat Typing for Molecular Tracing of Mycobacterium bovis in a High-Diversity Setting

Limitations of Spoligotyping and Variable-Number Tandem-Repeat Typing for Molecular Tracing of Mycobacterium bovis in a High-Diversity Setting

Investigating Transmission of Mycobacterium bovis in the United Kingdom in 2005 to 2008

Evaluation of Two Molecular Assays for Rapid Detection of Mycobacterium tuberculosis Resistance to Fluoroquinolones in High-Tuberculosis and -Multidrug-Resistance Settings

Contact Info

Product

Resources

About