title: [Genetic analysis reveals misidentification of Mycobacterium lentiflavum as Mycobacterium intracellulare by the COBAS TaqMan MAI test].
abstract: OBJECTIVE
  To evaluate COBAS TaqMan MAI test misidentification of Mycobacterium lentiflavum as Mycobacterium intracellulare.
  
  
  METHODS
  Preliminary comparative analysis identified 13 clinical isolates used in this study as COBAS Amplicor MAV and MIN-negative but COBAS TaqMan MAI-positive. The COBAS TaqMan MAI test limit of detection and reproducibility were evaluated by tenfold dilution series from 3 x 10(8) CFU/mL. Isolate 16S rDNA nucleotide sequences were compared with Mycobacterium avium and M. intracellulare.
  
  
  RESULTS
  Discrepancies were observed between isolates identified as M. lentiflavum by 16S rDNA sequencing and as M. intracellulare by the COBAS TaqMan MAI test. The false-positive results were verified by sequence comparison of a randomly sampled clinical isolate and the M. intracellulare reference strain. Sequence analysis of M. lentiflavum and M. intracellulare 16S rDNA amplification products showed at least 3 mismatches between species. The high identity in the sequence was found for M. intracellulare by COBAS TaqMan MAI.
  
  
  CONCLUSIONS
  In Japan, commercially available nucleic acid probe- and amplification-based tests cannot identify M. lentiflavum. Correct identification, though challenging, is possible using standard cultivation procedures for colony growth. Misleading results using the COBAS TaqMan MAI kit may lead to erroneous diagnoses.
authors.forename: Motohisa
authors.initials: M
authors.lastname: Tomita
authors.forename: Shiomi
authors.initials: S
authors.lastname: Yoshida
authors.forename: Kazunari
authors.initials: K
authors.lastname: Tsuyuguchi
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Suzuki
authors.forename: Masaji
authors.initials: M
authors.lastname: Okada
authors.forename: Seiji
authors.initials: S
authors.lastname: Hayashi
mesh_terms: D001483:Base Sequence; D015269:Mycobacterium avium Complex / Q000235:genetics* / Q000302:isolation & purification*; D009170:Nontuberculous Mycobacteria / Q000235:genetics* / Q000302:isolation & purification*; D011933:Reagent Kits, Diagnostic
chemical_list: D011933:Reagent Kits, Diagnostic