title: Prospective evaluation of pyrosequencing for the rapid detection of isoniazid and rifampin resistance in clinical Mycobacterium tuberculosis isolates.
abstract: A pyrosequencing-based method for the rapid detection of isoniazid (INH) and rifampin (RIF) resistance in Mycobacterium tuberculosis was evaluated in clinical practice. The method can detect the INH resistance-causing katG315 mutation, and all mutations in the RIF resistance-determining rpoB core region, in less than 6 h from cultured isolates. The method was first validated with 42 isolates, and was subsequently prospectively evaluated with 91 isolates, including clinical isolates and external quality control assessment strains, over a period of 2.5 years. The pyrosequencing results of clinical isolates were available, on average, 19 days earlier (median 19 days; range 3-43 days) than conventional susceptibility testing results. The composite data showed that the sensitivity of pyrosequencing for detecting resistance correctly was 66.7% for INH and 97.4% for RIF. The specificity of pyrosequencing was 100% for both drugs. Acceptable sensitivity for detecting resistance and the rapidness of pyrosequencing make it a valuable tool in the clinical setting.
authors: Mycobacterial Reference Laboratory, National Public Health Institute, Turku, Finland. johanna.makinen@ktl.fi
authors: H J
authors: HJ
authors: Marttila
authors: J
authors: J
authors: Mäkinen
authors: M
authors: M
authors: Marjamäki
authors: H
authors: H
authors: Soini
mesh_terms: D019943:Amino Acid Substitution / Q000235:genetics; D000995:Antitubercular Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D002374:Catalase / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics*; D012321:DNA-Directed RNA Polymerases; D024881:Drug Resistance, Bacterial; D006801:Humans; D007538:Isoniazid / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests / Q000379:methods; D020125:Mutation, Missense; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000235:genetics; D011446:Prospective Studies; D012293:Rifampin / Q000494:pharmacology*; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA / Q000379:methods*
chemical_list: D000995:Antitubercular Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C505805:rpoB protein, Mycobacterium tuberculosis; D002374:Catalase; C480353:katG protein, Mycobacterium tuberculosis; D012321:DNA-Directed RNA Polymerases; D007538:Isoniazid; D012293:Rifampin