title: Drug resistance in Mycobacterium tuberculosis.
abstract: Anti-tuberculosis drugs are a two-edged sword. While they destroy pathogenic M. tuberculosis they also select for drug resistant bacteria against which those drugs are then ineffective. Global surveillance has shown that drug resistant Tuberculosis is widespread and is now a threat to tuberculosis control programs in many countries. Application of molecular methods during the last decade has greatly changed our understanding of drug resistance in tuberculosis. Application of molecular epidemiological methods was also central to the description of outbreaks of drug resistance in Tuberculosis. This review describes recommendations for Tuberculosis treatment according to the WHO guidelines, the drug resistance problem in the world, mechanisms of resistance to first line and second line drugs and applications of molecular methods to detect resistance causing gene mutations. It is envisaged that molecular techniques may be important adjuncts to traditional culture based procedures to rapidly screen for drug resistance. Prospective analysis and intervention to prevent transmission may be particularly helpful in areas with ongoing transmission of drug resistant strains as recent mathematical modeling indicate that the burden of MDR-TB cannot be contained in the absence of specific efforts to limit transmission.
authors.affiliation: Division of Molecular Biology and Human Genetics, Department of Biomedical Science, Faculty of Health Science, Tygerberg, Stellenbosch University, South Africa.
authors.forename: Rabia
authors.initials: R
authors.lastname: Johnson
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Streicher
authors.forename: Gail E
authors.initials: GE
authors.lastname: Louw
authors.forename: Robin M
authors.initials: RM
authors.lastname: Warren
authors.forename: Paul D
authors.initials: PD
authors.lastname: van Helden
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Victor
mesh_terms: D000995:Antitubercular Agents / Q000627:therapeutic use; D004252:DNA Mutational Analysis; D004196:Disease Outbreaks; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D006287:Health Planning Guidelines; D006801:Humans; D008826:Microbial Sensitivity Tests; D008967:Molecular Biology / Q000379:methods; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D011159:Population Surveillance; D014376:Tuberculosis / Q000188:drug therapy / Q000517:prevention & control* / Q000635:transmission; D014944:World Health Organization
chemical_list: D000995:Antitubercular Agents