Couto Natacha, Monchique Cláudia, Belas Adriana, Marques Cátia, Gama Luís T, Pomba Constança
Antimicrobial and Biocide Resistance Laboratory, CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa (FMV-UL), Av. da Universidade Técnica, 1300-477 Lisboa, Portugal.
Animal Genetic Resources, CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa (FMV-UL), Av. da Universidade Técnica, 1300-477 Lisboa, Portugal.
J Antimicrob Chemother. 2016 Jun;71(6):1479-87. doi: 10.1093/jac/dkw029. Epub 2016 Mar 3.
The objective of this study was to investigate the evolution of resistance to antimicrobials, corresponding mechanisms and molecular characteristics of Staphylococcus spp., between 1999 and 2014.
Susceptibility to 38 antimicrobials was determined for 632 clinical staphylococcal isolates obtained from companion animals (dogs, cats, horses and other animals). Twenty antimicrobial resistance genes, including mecA and mecC, were screened by PCR. Methicillin-resistant staphylococci were characterized by spa (Staphylococcus aureus), SCCmec, MLST and PFGE typing. Statistical analyses were performed using SAS v9.3 and differences were considered relevant if P ≤ 0.05.
The mecA gene was identified in 74 staphylococcal isolates (11.6%): 11 MRSA (40.7%), 40 methicillin-resistant Staphylococcus pseudintermedius (MRSP; 8.7%) and 23 methicillin-resistant CoNS (26.7%). Resistance to the majority of antimicrobials and the number of mecA-positive isolates increased significantly over time. Eighteen spa types were identified, including two new ones. MRSA isolates were divided into three PFGE clusters that included ST22-IV, ST105-II, ST398-V and ST5-VI. Most methicillin-resistant Staphylococcus epidermidis isolates were of clonal complex (CC) 5, including a new ST, and clustered in eight PFGE clusters. MRSP were grouped into five PFGE clusters and included ST45-NT, ST71-II-III, ST195-III, ST196-V, ST339-NT, ST342-IV and the new ST400-III. Methicillin-resistant Staphylococcus haemolyticus clustered in two PFGE clusters.
The significant increase in antimicrobial-resistant and mecA-positive isolates in recent years is worrying. Furthermore, several isolates are MDR, which complicates antimicrobial treatment and increases the risk of transfer to humans or human isolates. Several clonal lineages of MRSA and methicillin-resistant S. epidermidis circulating in human hospitals and the community were found, suggesting that companion animals can become infected with and contribute to the dissemination of highly successful human clones. Urgent measures, such as determination of clinical breakpoints and guidelines for antimicrobial use, are needed.
本研究旨在调查1999年至2014年间葡萄球菌属对抗菌药物的耐药性演变、相应机制及分子特征。
对从伴侣动物（狗、猫、马及其他动物）分离得到的632株临床葡萄球菌菌株测定其对38种抗菌药物的敏感性。通过PCR筛选20种抗菌耐药基因，包括mecA和mecC。耐甲氧西林葡萄球菌通过spa（金黄色葡萄球菌）、SCCmec、多位点序列分型（MLST）和脉冲场凝胶电泳（PFGE）分型进行鉴定。使用SAS v9.3进行统计分析，P≤0.05时差异被认为具有统计学意义。
在74株葡萄球菌菌株中鉴定出mecA基因（11.6%）：11株耐甲氧西林金黄色葡萄球菌（MRSA，40.7%）、40株耐甲氧西林中间葡萄球菌（MRSP，8.7%）和23株耐甲氧西林凝固酶阴性葡萄球菌（CoNS，26.7%）。随着时间推移，对大多数抗菌药物的耐药性及mecA阳性菌株数量显著增加。鉴定出18种spa型，包括两种新的spa型。MRSA菌株分为三个PFGE簇，包括ST22-IV、ST105-II、ST398-V和ST5-VI。大多数耐甲氧西林表皮葡萄球菌菌株属于克隆复合体（CC）5，包括一个新的序列型，且聚集在八个PFGE簇中。MRSP分为五个PFGE簇，包括ST45-NT、ST71-II-III、ST195-III、ST196-V、ST339-NT、ST(342-IV)和新的ST400-III。耐甲氧西林溶血葡萄球菌聚集在两个PFGE簇中。
近年来抗菌药物耐药菌株和mecA阳性菌株数量显著增加令人担忧。此外，一些菌株为多重耐药，这使抗菌治疗复杂化，并增加了传播给人类或人类感染的风险。发现了在人类医院和社区中传播的几种MRSA和耐甲氧西林表皮葡萄球菌的克隆谱系，表明伴侣动物可能感染并促成高致病性人类克隆的传播。需要采取紧急措施，如确定临床断点和抗菌药物使用指南。
