Chew Ka Lip, Cheng Janet W S, Hudaa Osman Nurul, Lin Raymond T P, Teo Jeanette W P
National 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 138623, Republic of Singapore.
J Med Microbiol. 2017 Oct;66(10):1443-1447. doi: 10.1099/jmm.0.000576. Epub 2017 Sep 6.
To 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.
为了鉴定脓肿分枝杆菌复合群的成员，重点关注菌种鉴定与克拉霉素相关基因多态性之间的相关性，这些多态性导致诱导性和组成型大环内酯耐药性。采用聚合酶链反应（PCR）和测序分析来阐明亚种、erm(41)基因型以及rrl突变的存在情况。马赛分枝杆菌亚种是主要的亚种（70.2%），其次是脓肿分枝杆菌亚种（23.8%）和博列特分枝杆菌亚种（5.9%）。大多数脓肿分枝杆菌和博列特分枝杆菌分离株具有T28 erm(41)序列变异，对克拉霉素呈诱导性耐药。所有马赛分枝杆菌均携带截短的erm(41)，且对克拉霉素大多敏感（98.3%）。涉及rrl突变的组成型耐药很少见，仅在2株分离株中出现（2.2%）。亚种鉴定不足以预测克拉霉素敏感性，需要通过测序来确定基因耐药性。在我们的研究背景下，rrl突变并不常见，可能不是一项必需的检测。
