title: The drug resistance profile of Mycobacterium abscessus group strains from Korea.
abstract: BACKGROUND
  Bacteria of the Mycobacterium abscessus group are the second most common pathogens responsible for lung disease caused by nontuberculous mycobacteria in Korea. There is still a lack of studies investigating the genetic mechanisms involved in M. abscessus resistance to antibiotics other than clarithromycin. This study investigated the characteristics of drug resistance exhibited by M. abscessus clinical isolates from Korea.
  
  
  METHODS
  We performed drug susceptibility testing for a total of 404 M. abscessus clinical strains. Subspecies were differentiated by molecular biological methods and examined for mutations in drug resistance-related genes.
  
  
  RESULTS
  Of the 404 strains examined, 202 (50.00%), 199 (49.26%), and 3 (0.74%) strains were identified as M. abscessus, M. massiliense, and M. bolletii, respectively. Of the 152 clarithromycin-resistant strains, 6 possessed rrl mutations, while 4 of the 30 amikacin-resistant strains contained rrs mutations, and 5 of the 114 quinolone-resistant strains had gyr mutations. All mutant strains had high minimal inhibitory concentration values for the antibiotics.
  
  
  CONCLUSIONS
  Our results showed the distribution of the strains with mutations in drug resistance-related genes was low in the M. abscessus group. Furthermore, we performed drug susceptibility testing and sequence analyses to determine the characteristics of these genes in the M. abscessus group.
authors.affiliation: Korean Institute of Tuberculosis, Chengwon, Korea.
authors.forename: Seung Heon
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Korean Institute of Tuberculosis, Chengwon, Korea.
authors.forename: Hee Kyung
authors.initials: HK
authors.lastname: Yoo
authors.affiliation: Korean Institute of Tuberculosis, Chengwon, Korea.
authors.forename: Seol Hee
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Won-Jung
authors.initials: WJ
authors.lastname: Koh
authors.affiliation: Korean Institute of Tuberculosis, Chengwon, Korea.
authors.forename: Chang Ki
authors.initials: CK
authors.lastname: Kim
authors.affiliation: Korean Institute of Tuberculosis, Chengwon, Korea.
authors.forename: Young Kil
authors.initials: YK
authors.lastname: Park
authors.affiliation: Korean Institute of Tuberculosis, Chengwon, Korea.
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Kim
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D017291:Clarithromycin / Q000494:pharmacology; D027081:DNA Gyrase / Q000235:genetics; D024881:Drug Resistance, Bacterial; D006801:Humans; D008780:Methyltransferases / Q000235:genetics; D008826:Microbial Sensitivity Tests; D009154:Mutation; D009161:Mycobacterium / Q000187:drug effects / Q000302:isolation & purification*; D009165:Mycobacterium Infections, Nontuberculous / Q000175:diagnosis / Q000382:microbiology*; D056910:Republic of Korea; D017422:Sequence Analysis, DNA
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D008780:Methyltransferases; D027081:DNA Gyrase; D017291:Clarithromycin
keywords: Drug resistance; Mutation; Mycobacterium abscessus group