title: Further isolation of Mycobacterium abscessus subsp. abscessus and subsp. bolletii in different regions of Japan and susceptibility of these isolates to antimicrobial agents.
abstract: The aim of this study was to genetically analyse Mycobacterium abscessus subsp. abscessus (hereafter M. abscessus) and M. abscessus subsp. bolletii (hereafter M. bolletii) isolates from six different regions of Japan and to determine the antimicrobial susceptibility of these isolates. Subspeciation of 143 clinical isolates of M. abscessus group was done by comparative sequence analysis of the rpoB and hsp65 genes and the internal transcribed spacer (ITS) region. Genetic analysis led to the identification of 90 M. abscessus (62.9%) and 53 M. bolletii (37.1%; comprising 50 'M. massiliense' and 3 'M. bolletii' in the old nomenclature). No significant differences were found between the M. abscessus and M. bolletii isolates in any characteristics. Susceptibility to clarithromycin and linezolid for M. bolletii isolates was significantly higher than that for M. abscessus (P<0.05). Moreover, the results demonstrated that 82 M. abscessus isolates with T28 sequevar were resistant to clarithromycin owing to the expression of erm(41), which was induced by clarithromycin, whilst 8 isolates with C28 sequevar were susceptible. Acquired clarithromycin resistance in 'M. bolletii' isolates was significantly associated with previous Mycobacterium avium complex (MAC) treatment compared with that of M. abscessus isolates; however, intrinsic inducible susceptibility of M. abscessus isolates was not associated with MAC treatment. However, acquired resistance to clarithromycin by mutation in the rrl gene encoding 23S rRNA did not occur in 14 of 18 resistant isolates. Strains with acquired resistance to clarithromycin and mutation in rrl consisted of two M. bolletii (one 'M. massiliense' and one 'M. bolletii') and two M. abscessus T28 sequevar.
authors.affiliation: Clinical Research Center, National Hospital Organization Kinki-chuo Chest Medical Center, 1180 Nagasone-cho, Kita-ku Sakai, Osaka 591-8555, Japan. dustin@kch.hosp.go.jp
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: Motohisa
authors.initials: M
authors.lastname: Tomita
authors.forename: Masaji
authors.initials: M
authors.lastname: Okada
authors.forename: Seiji
authors.initials: S
authors.lastname: Hayashi
authors.forename: Tomotada
authors.initials: T
authors.lastname: Iwamoto
authors.forename: Hajime
authors.initials: H
authors.lastname: Saito
mesh_terms: D000081:Acetamides / Q000494:pharmacology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D018834:Chaperonin 60 / Q000235:genetics; D017291:Clarithromycin / Q000494:pharmacology; D021901:DNA, Intergenic / Q000235:genetics; D012321:DNA-Directed RNA Polymerases; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D007564:Japan; D000069349:Linezolid; D008297:Male; D008780:Methyltransferases / Q000235:genetics; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009161:Mycobacterium / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D009164:Mycobacterium Infections / Q000188:drug therapy* / Q000382:microbiology; D023303:Oxazolidinones / Q000494:pharmacology; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D000081:Acetamides; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D018834:Chaperonin 60; D021901:DNA, Intergenic; D023303:Oxazolidinones; D012338:RNA, Ribosomal, 23S; C074119:heat-shock protein 65, Mycobacterium; C505805:rpoB protein, Mycobacterium tuberculosis; D008780:Methyltransferases; C431709:ErmA protein, Bacteria; D012321:DNA-Directed RNA Polymerases; D017291:Clarithromycin; D000069349:Linezolid
keywords: Clarithromycin; Genetic distribution; In vitro susceptibility; Mycobacterium abscessus subsp. abscessus; Mycobacterium abscessus subsp. bolletii