Videla Ricardo, Solyman Samar M, Brahmbhatt Akshar, Sadeghi Leslie, Bemis David A, Kania Stephen A
Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee , Knoxville, Tennessee.
Microb Drug Resist. 2018 Jan/Feb;24(1):83-88. doi: 10.1089/mdr.2016.0250. Epub 2017 May 15.
Staphylococcus pseudintermedius is the primary cause of canine pyoderma and has been associated with diseases in other animals, including human beings. A high prevalence of methicillin and multidrug resistance has been reported in this bacterium in some geographic regions of the United States. Multilocus sequence type (MLST) 68 was implicated, initially, as the major clonal genotype based on a limited number of samples. The objectives of this study were to determine the population genetics of S. pseudintermedius isolated from a cross-section of the United States using a seven-locus multilocus sequence typing method, to identify clonal complexes (CCs), and to correlate sequence types with antimicrobial susceptibility profiles. A total of 190 S. pseudintermedius with 86 different MLSTs were detected and the constituents of three major CCs of methicillin-resistant S. pseudintermedius (MRSP), CC68, CC71, and CC84, were identified. Different patterns of resistance were associated with each CC. CC71 from the United States had notable differences with CC71 studied on other continents with chloramphenicol, tetracycline, and trimethoprim/sulfamethoxazole resistance. Some isolates with resistance to the broadest range of drugs tested, including that to chloramphenicol, had STs unrelated to the major CCs, suggesting the potential for the emergence of new clonal populations of MRSP that are resistant to most therapeutically useful antimicrobials.
中间型假单胞菌是犬脓皮病的主要病因，并且与包括人类在内的其他动物的疾病有关。在美国的一些地理区域，已报道该细菌中耐甲氧西林和多重耐药的发生率很高。最初，基于有限数量的样本，多位点序列类型（MLST）68被认为是主要的克隆基因型。本研究的目的是使用七基因座多位点序列分型方法确定从美国不同地区分离出的中间型假单胞菌的群体遗传学，鉴定克隆复合体（CCs），并将序列类型与抗菌药物敏感性谱相关联。共检测到190株中间型假单胞菌，具有86种不同的MLSTs，并鉴定出耐甲氧西林中间型假单胞菌（MRSP）的三个主要CCs，即CC68、CC71和CC84的组成成分。每个CC都与不同的耐药模式相关。来自美国的CC71与在其他大陆研究的CC71在对氯霉素、四环素和甲氧苄啶/磺胺甲恶唑的耐药性方面存在显著差异。一些对所测试的最广泛药物具有耐药性的分离株，包括对氯霉素的耐药性，其STs与主要CCs无关，这表明可能会出现对大多数治疗有用抗菌药物耐药的新的MRSP克隆群体。
