• Ka Lip Chew, Janet W S Cheng, Nurul Hudaa Osman, LinRaymond T PRTPNational University Hospital, Department of Laboratory Medicine, Division of Microbiology, Singapore 119074, Republic of Singapore.National Public Health Laboratory, Ministry of Health, 3 Biopolis Drive, Synapse #05-14/16, Singapore 13862, and Jeanette W P Teo.
• National University Hospital, Department of Laboratory Medicine, Division of Microbiology, Singapore 119074, Republic of Singapore.
• J. Med. Microbiol. 2017 Oct 1; 66 (10): 1443-1447.

AbstractTo characterize members of the Mycobacterium abscessus complex, with an emphasis on the correlation between species identification and clarithromycin associated genetic polymorphisms that contribute to inducible and constitutive macrolide resistance. PCR and sequencing analysis was used to elucidate the subspecies, erm(41) genotypes and the presence of rrl mutations. M. abscessus subsp. massiliense was the dominant subspecies (70.2 %), followed by M. abscessus subsp. abscessus (23.8 %) and M. abscessus subsp. bolletii (5.9 %). The majority of M. abscessus and M. bolletii isolates possessed T28 erm(41) sequevar and were inducibly resistant to clarithromycin. All M. massiliense carried the truncated erm(41) and were largely clarithromycin-susceptible (98.3 %). Constitutive resistance involving rrl mutations was rare and seen in only 2 isolates (2.2 %). Subspecies identification was insufficient to predict clarithromycin susceptibility and required the genetic resistance to be determined via sequencing. In our context, rrl mutations were uncommon and may not be an essential test.

17 keywords...

hide…