摘要
目的:对引起中枢神经系统感染的一株罕见粘液型溶血葡萄球菌(S.haemolyticus)表型及基因组特征进行分析。方法:收集一株导致中枢神经系统感染粘液型溶血葡萄球菌,通过生物膜形成实验、药敏实验分析生物膜形成和耐药表型,全基因组测序分析其耐药等基因特征。结果:本例溶血葡萄球菌呈粘液型,可见拉丝现象,属于苯唑西林耐药凝固酶阴性葡萄球菌(MRCoNS),同时对红霉素、克林霉素、左氧氟沙星耐药,对万古霉素、利奈唑胺敏感,比普通非粘液型溶血葡萄球菌更易形成生物膜,MLST显示该菌为ST1型,携带mecA、aph(3′)-IIIa、aac(6′)-Ie、aph(2″)-Ia等8种耐药基因,mecA基因由类似Tn6191的转座子所携带。结论:呈粘液型菌落特征的溶血葡萄球菌在临床上极为罕见,该变异体比通常的非粘液型菌落更易形成生物膜且呈现出多重耐药现象。临床上应关注此类葡萄球菌的粘液变异体,这有助于其早期识别和感染防控。
Objective:To analyze the phenotypic and genetic characteristics of a rare strain of mucoid Staphylococcus haemolyticus(S.haemolyticus)that causes central nervous system infection.Methods:A strain of mucoid S.haemolyticus that caused central nervous system infection was collected,and the biofilm formation and drug resistance phenotypes were analyzed by biofilm formation assay and antibiotic susceptibility assay(AST).The genome characteristics associated with drug resistance were analyzed by whole genome sequencing.Results:The S.haemolyticus showed mucoid colony with visible string phenomenon,belonging to oxacillin-resistant coagulase-negative staphylococci(MRCoNS).AST assay showed the strain was resistant to erythromycin,clindamycin and levofloxacin,but was susceptible to vancomycin and linezolid.It could form more biofilm than the non-mucoid S.haemolyticus strain.MLST revealed the strain belonged to sequence type 1(ST1)and carried 8 drug resistance genes including mecA,aph(3′)-IIIa,aac(6′)-Ie,aph(2″)-Ia.The mecA gene was carried by a Tn6191-like transposon.Conclusion:S.hemolyticus with mucoid colony characteristics was extremely rare in clinical practice,and this variant was more likely to form biofilm than the usual non-mucous S.hemolyticus and exhibited multidrug resistance.Clinical attention should be paid to the mucoid variant of S.haemolyticus,which is helpful for their early identification and infection prevention and control.
作者
程芳
李晓凤
董秀涛
马建萍
崔晓笛
郝明巨
CHENG Fang;LI Xiaofeng;DONG Xiutao(Department of Clinical Laboratory Medicine,the First Affiliated Hoepital of Shandong First Medical Universily&Shandong Provincial Qianfoshan Hoepital,Shandong Jinan 250014)
出处
《医学检验与临床》
2023年第9期6-11,共6页
Medical Laboratory Science and Clinics
基金
山东省自然科学基金,项目编号:ZR2021MH078
济南市临床医学科技创新计划,项目编号:202134040。
关键词
溶血葡萄球菌
粘液型
耐药
生物膜
中枢神经系统感染
Staphylococcus hemolytica
Mucoid type
Drug resistance
Biofilm
Central nervous system infection
