Blog
About

  • Record: found
  • Abstract: found
  • Article: found
Is Open Access

Evaluation of rapid alternative methods for drug susceptibility testing in clinical isolates of Mycobacterium tuberculosis

Read this article at

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

      A study was carried out to compare the performance of a commercial method (MGIT) and four inexpensive drug susceptibility methods: nitrate reductase assay (NRA), microscopic observation drug susceptibility (MODS) assay, MTT test, and broth microdilution method (BMM). A total of 64 clinical isolates of Mycobacterium tuberculosis were studied. The Lowenstein-Jensen proportion method (PM) was used as gold standard. MGIT, NRA, MODS, and MTT results were available on an average of less than 10 days, whereas BMM results could be reported in about 20 days. Most of the evaluated tests showed excellent performance for isoniazid and rifampicin, with sensitivity and specificity values > 90%. With most of the assays, sensitivity for ethambutol was low (62-87%) whereas for streptomycin, sensitivity values ranged from 84 to 100%; NRA-discrepancies were associated with cultures with a low proportion of EMB-resistant organisms while most discrepancies with quantitative tests (MMT and BMM) were seen with isolates whose minimal inhibitory concentrations fell close the cutoff. MGIT is reliable but still expensive. NRA is the most inexpensive and easiest method to perform without changing the organization of the routine PM laboratory performance. While MODS, MTT, and BMM, have the disadvantage from the point of view of biosafety, they offer the possibility of detecting partial resistant strains. This study shows a very good level of agreement of the four low-cost methods compared to the PM for rapid detection of isoniazid, rifampicin and streptomycin resistance (Kappa values > 0.8); more standardization is needed for ethambutol.

      Related collections

      Most cited references 24

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

      Practical statistics for medical research. Douglas G. Altman, Chapman and Hall, London, 1991. No. of pages: 611. Price: £32.00

       Deborah Ashby (1991)
        Bookmark
        • Record: found
        • Abstract: not found
        • Article: not found

        Mycobacteria: laboratory methods for testing drug sensitivity and resistance

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

          Tuberculosis bacteriology. Technical note 11

          (1988)
            Bookmark

            Author and article information

            Affiliations
            [1 ] Instituto Nacional de Enfermedades Respiratorias ‘E. Coni’ Argentina
            Contributors
            Role: ND
            Role: ND
            Role: ND
            Journal
            mioc
            Memórias do Instituto Oswaldo Cruz
            Mem. Inst. Oswaldo Cruz
            Instituto Oswaldo Cruz, Ministério da Saúde (Rio de Janeiro )
            1678-8060
            August 2006
            : 101
            : 5
            : 535-542
            S0074-02762006000500009 10.1590/S0074-02762006000500009

            http://creativecommons.org/licenses/by/4.0/

            Product
            Product Information: SciELO Brazil
            Categories
            PARASITOLOGY
            TROPICAL MEDICINE

            Comments

            Comment on this article