title: [Detection of pncA mutation associated with pyrazinamide resistance in Mycobacterium tuberculosis by high-resolution melting cure analysis].
abstract: OBJECTIVE
  To evaluate the application of a high-resolution melting (HRM) curve analysis for rapid detection of pyrazinamide resistance in Mycobacterium tuberculosis (M. tuberculosis).
  
  
  METHODS
  Clinical isolates of M. tuberculosis were collected from Shenzhen from 2007 - 2009 and pncA mutations were characterized by sequence analysis. HRM analysis method was established and used to determine pncA gene mutation in 49 pncA mutant isolates and 78 wild type isolates. BCATEC MGIT 960 was used as the standard method to evaluate application of the HRM curve.
  
  
  RESULTS
  Among 49 pncA mutant isolates, 48 isolates were characterized as mutant and 1 isolate with double point mutations misclassified as wild type by using HRM detection. In 78 wild type isolates, HRM found 6 mutant isolates. Using the BCATEC MGIT 960 to detect pyrazinamide drug susceptibility, 62 isolates were found resistant and 65 were susceptible. Among the 62 resistant strains by HRM results 53 strains were resistant, and among the 65 susceptible stains by HRM results 64 were susceptible. Compared to the results of BACTEC MGIT 960, the sensitivity and specificity of HRM were 85.5% (53/62) and 98.5% (64/65), respectively. The Youden index was found to be 0.840.
  
  
  CONCLUSIONS
  The results showed a good correlation between HRM curve analysis and BACTEC MGIT 960. HRM curve analysis is a rapid and accurate method that can be used as a screening test for identification of resistance to pyrazinamide.
authors.affiliation: Department of Pathogenic Laboratory, Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China.
authors.forename: Chuang-yue
authors.initials: CY
authors.lastname: Hong
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.forename: Xiao-li
authors.initials: XL
authors.lastname: Liu
mesh_terms: D000581:Amidohydrolases / Q000235:genetics*; D000995:Antitubercular Agents / Q000494:pharmacology*; D017931:DNA Primers; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial; D005838:Genotype; D006801:Humans; D008826:Microbial Sensitivity Tests; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011718:Pyrazinamide / Q000494:pharmacology*; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA; D044366:Transition Temperature; D018088:Tuberculosis, Multidrug-Resistant / Q000175:diagnosis / Q000188:drug therapy* / Q000382:microbiology
chemical_list: D000995:Antitubercular Agents; D017931:DNA Primers; D004269:DNA, Bacterial; D011718:Pyrazinamide; D000581:Amidohydrolases; C487496:PncA protein, Mycobacterium tuberculosis