Authors: Causse, M.1; Ruiz, P.2; Gutierrez, J.B.1; Zerolo, J.2; Casal, M.3

Source: The International Journal of Tuberculosis and Lung Disease, Volume 12, Number 12, December 2008 , pp. 1456-1460(5)

Publisher: International Union Against Tuberculosis and Lung Disease


Abstract:

SETTINGS: Molecular methods frequently used in laboratories can now give us useful information about low growth bacteria.

OBJECTIVE: To evaluate the new GenoType® MTBDRplus assay for its ability to detect mutations in the 81-bp hotspot region of the rpoB gene, mutations in codon 315 of the katG gene and alterations in the inhA promoter region.

DESIGN: Prospective resistance to rifampicin (RMP) and isoniazid (INH) study using Mycobacterium tuberculosis positive specimens and cultures comparing the results of GenoType MTBDRplus with those obtained phenotypically with the Bactec MGIT (Mycobacterial Growth Indicator Tube) 960.

RESULTS: In 59 specimens (18 smear microscopy samples and 41 solid and liquid medium cultures), mutations were detected in all of 36 M. tuberculosis strains phenotypically resistant to RMP (100%), and in 35 of 37 strains phenotypically resistant to INH (94.59%). The new assay prompted a 21.6% increase in the direct detection of INH resistance in the strains studied, due to the incorporation of inhA promoter region probes in the test.

CONCLUSIONS: The GenoType MTBDRplus assay is a valid method for detecting the most common mutations in strains resistant to RMP and INH. However, further phenotypic testing is required, as the assay failed to detect 100% of INH and RMP resistance. 
Keywords: GenoType MTBDRplus; Mycobacterium tuberculosis; rifampicin; isoniazid; resistance

Document Type: Regular paper

Affiliations: 1: Microbiology Service, Reina Sofia University Hospital, Cordoba, Spain 2: Mycobacteria Reference Centre, Department of Microbiology, Faculty of Medicine, Cordoba University, Cordoba, Spain 3: Microbiology Service, Reina Sofia University Hospital, Cordoba, Spain; and Mycobacteria Reference Centre, Department of Microbiology, Faculty of Medicine, Cordoba University, Cordoba, Spain

Saiba mais em: http://www.ingentaconnect.com/content/iuatld/ijtld/2008/00000012/00000012/art00020

Sobre a REDE-TB

A Rede Brasileira de Pesquisa em Tuberculose (REDE-TB) é uma Organização Não Governamental (ONG) de direito privado sem fins lucrativos, preocupada em auxiliar no desenvolvimento não só de novos medicamentos, novas vacinas, novos testes diagnósticos e novas estratégias de controle de TB, mas também na validação dessas inovações tecnológicas, antes de sua comercialização no país e/ou de sua implementação nos Programa de Controle de TB no País.


bt2

Contato

E-mail: redetb.rp@gmail.com

Tel: +55 (21)3938 - 2426
Tel/ Fax: +55 (21)3938 - 2431.

Endereço: Avenida Carlos Chagas Filho, 791, Cidade Universitária - Ilha do Fundão, Rio de Janeiro, RJ - Brasil. CEP: 21941-904

Assine a newsletter da REDE-TB

Curta REDE-TB no Facebook