title: Broad-range PCR coupled with mass-spectrometry for the detection of Mycobacterium tuberculosis drug resistance.
abstract: BACKGROUND
  The need to limit the spread of drug-resistant Mycobacterium tuberculosis requires rapid detection of resistant strains. The present study aimed to evaluate a commercial assay using broad-range PCR coupled with electrospray ionization mass spectrometry (PCR/ESI-MS) for the rapid detection of isoniazid (INH) and rifampin (RIF) resistance in M. tuberculosis strains isolated from Romanian patients with pulmonary tuberculosis.
  
  
  METHODS
  PCR/ESI-MS was used to detect genotypic resistance to RIF and INH in a panel of 63 M. tuberculosis isolates phenotypically characterized using the absolute concentration method on Löwenstein-Jensen medium.
  
  
  RESULTS
  Thirty-eight (60%) strains were susceptible to both drugs, 22 (35%) were RIF and INH resistant, one was INH mono-resistant and two were RIF mono-resistant. The sensitivity for INH and RIF resistance mutations detection were 100% and 92% respectively, with a specificity of more than 95% for each drug.
  
  
  CONCLUSIONS
  PCR/ESI-MS is a good method for the detection of RIF and INH resistance and might represent an alternative to other rapid diagnostic tests for the detection of genetic markers of resistance in M. tuberculosis isolates.
authors.affiliation: MD, PhD, National Institute for Infectious Diseases "Prof. Dr. Matei Balş", Bucharest, Romania, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
authors.forename: Dragoş
authors.initials: D
authors.lastname: Florea
authors.affiliation: MD, PhD, National Institute for Infectious Diseases "Prof. Dr. Matei Balş", Bucharest, Romania.
authors.forename: Dan
authors.initials: D
authors.lastname: Oţelea
authors.affiliation: MD, Research Center Borstel, Borstel, Germany.
authors.forename: Ioana D
authors.initials: ID
authors.lastname: Olaru
authors.affiliation: MD, PhD, National Institute for Infectious Diseases "Prof. Dr. Matei Balş", Bucharest, Romania, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
authors.forename: Adriana
authors.initials: A
authors.lastname: Hristea
keywords: MDR-TB; Mycobacterium tuberculosis; broad-range PCR; electrospray ionization mass-spectrometry