90
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      Acquired Resistance to Bedaquiline and Delamanid in Therapy for Tuberculosis.

      Read this article at

      ScienceOpenPublisherPubMed
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Treatment of multidrug-resistant Mycobacterium tuberculosis is a challenge. This letter describes the emergence of resistance to new therapies, bedaquiline and delamanid.

          Related collections

          Most cited references3

          • Record: found
          • Abstract: found
          • Article: not found

          Dynamic population changes in Mycobacterium tuberculosis during acquisition and fixation of drug resistance in patients.

          Drug-resistant tuberculosis poses a growing challenge to global public health. However, the diversity and dynamics of the bacterial population during acquisition of drug resistance have yet to be carefully examined. Whole-genome sequencing was performed on 7 serial Mycobacterium tuberculosis (M. tuberculosis) populations from 3 patients during different stages in the development of drug resistance. The population diversity was assessed by the number and frequencies of unfixed mutations in each sample. For each bacterial population, 8-41 unfixed mutations were monitored by the fraction of single-nucleotide polymorphisms at specific loci. Among them, as many as 4 to 5 resistance-conferring mutations were transiently detected in the same single sputum, but ultimately only a single type of mutant was fixed. In addition, we identified 14 potential compensatory mutations that occurred during or after the emergence of resistance-conferring mutations. M. tuberculosis population within patients exhibited considerable genetic diversity, which underwent selections for most fit resistant mutant. These findings have important implications and emphasize the need for early diagnosis of tuberculosis to decrease the chance of evolving highly fit drug-resistant strains.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: found

            Emerging novel and antimicrobial-resistant respiratory tract infections: new drug development and therapeutic options

            Summary The emergence and spread of antimicrobial-resistant bacterial, viral, and fungal pathogens for which diminishing treatment options are available is of major global concern. New viral respiratory tract infections with epidemic potential, such as severe acute respiratory syndrome, swine-origin influenza A H1N1, and Middle East respiratory syndrome coronavirus infection, require development of new antiviral agents. The substantial rise in the global numbers of patients with respiratory tract infections caused by pan-antibiotic-resistant Gram-positive and Gram-negative bacteria, multidrug-resistant Mycobacterium tuberculosis, and multiazole-resistant fungi has focused attention on investments into development of new drugs and treatment regimens. Successful treatment outcomes for patients with respiratory tract infections across all health-care settings will necessitate rapid, precise diagnosis and more effective and pathogen-specific therapies. This Series paper describes the development and use of new antimicrobial agents and immune-based and host-directed therapies for a range of conventional and emerging viral, bacterial, and fungal causes of respiratory tract infections.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Directed mutagenesis of Mycobacterium smegmatis 16S rRNA to reconstruct the in vivo evolution of aminoglycoside resistance in Mycobacterium tuberculosis

              Drug resistance in Mycobacterium tuberculosis is a global problem, with major consequences for treatment and public health systems. As the emergence and spread of drug-resistant tuberculosis epidemics is largely influenced by the impact of the resistance mechanism on bacterial fitness, we wished to investigate whether compensatory evolution occurs in drug-resistant clinical isolates of M. tuberculosis. By combining information from molecular epidemiology studies of drug-resistant clinical M. tuberculosis isolates with genetic reconstructions and measurements of aminoglycoside susceptibility and fitness in Mycobacterium smegmatis, we have reconstructed a plausible pathway for how aminoglycoside resistance develops in clinical isolates of M. tuberculosis. Thus, we show by reconstruction experiments that base changes in the highly conserved A-site of 16S rRNA that: (i) cause aminoglycoside resistance, (ii) confer a high fitness cost and (iii) destabilize a stem-loop structure, are associated with a particular compensatory point mutation that restores rRNA secondary structure and bacterial fitness, while maintaining to a large extent the drug-resistant phenotype. The same types of resistance and associated mutations can be found in M. tuberculosis in clinical isolates, suggesting that compensatory evolution contributes to the spread of drug-resistant tuberculosis disease.
                Bookmark

                Author and article information

                Journal
                N. Engl. J. Med.
                The New England journal of medicine
                1533-4406
                0028-4793
                Nov 12 2015
                : 373
                : 20
                Affiliations
                [1 ] University of Zurich, Zurich, Switzerland.
                Article
                NIHMS742758
                10.1056/NEJMc1505196
                26559594
                8057e1b3-7d9b-4098-9edf-da090d8368b8
                History

                Comments

                Comment on this article