CSOM患者分泌物中耐甲氧西林金黄色葡萄球菌的基因分型及耐药特征  

The Genotypes and Drug Resistance Characteristics of Methicillin-resistant Staphylococcus Aureus in Secretions of CSOM Patients

作　　者：赵俊玲 宫亮 刘丹 Zhao Junling;Gong Liang;Liu Dan(The First Affiliated Hospital of Jinzhou Medical University,Jinzhou 121000 China)

机构地区：[1]锦州医科大学附属第一医院,辽宁锦州121000

出　　处：《锦州医科大学学报》2023年第2期44-50,共7页Journal of Jinzhou Medical University

基　　金：辽宁省教育厅科学研究项目,项目编号:320.71。

摘　　要：目的 探究慢性化脓性中耳炎(chronic suppurative otitis media, CSOM)患者中耳分泌物耐甲氧西林金黄色葡萄球菌(methicillin-resistant staphylococcus aureus, MRSA)分离株的基因分型及耐药特征。方法 选取2019年1月至2020年12月锦州医科大学附属第一医院收治的120例CSOM患者,治疗时采集患者中耳分泌物进行细菌分离,对分离病原菌进行培养、鉴定及药敏试验,分析CSOM患者中耳积液的病原菌临床分布特征,根据金黄色葡萄球菌感染情况,分为MRSA和甲氧西林敏感金黄色葡萄球菌(methicillin-resistant staphylococcus aureus, MRSA),采用PCR扩增法检测MRSA的基因分型,采用K-B纸片扩散法检测不同基因型MRSA和MSSA对临床常用抗菌药物的耐药性。结果 120份中耳分泌物标本中共培养分离出病原菌149株,其中,革兰氏阴性菌45株(30.20%),以铜绿假单胞菌(19株,12.75%)和肺炎克雷伯菌(16株,10.74%)为主;革兰氏阳性菌96株(64.43%),以金黄色葡萄球菌(73株,48.99%)为主;检出真菌8株(5.36%),均为假丝酵母菌。73株金黄色葡萄球菌经药敏试验共检出MRSA 26株,MSSA 47株;26株MRSA菌株的mecA基因携带率为100%,多重PCR法共检出SCCmecⅡ型7株(26.92%),SCCmecⅢ型15株(57.69%),SCCmecⅣa型4株(15.38%)。MRSA菌株对青霉素、苯唑西林、庆大霉素、左氧氟沙星、利福平和呋喃妥因的耐药率明显高于MSSA菌株(P<0.05);不同SCCmec基因分型MRSA菌株对左氧氟沙星、环丙沙星和莫西沙星的耐药率比较,SCCmecⅢ型>SCCmecⅡ型>SCCmecⅣa型(P<0.05)。结论 金黄色葡萄球菌是CSOM患者常见的感染病原菌,分离的MRSA菌株均携带mecA基因,SCCmec基因型以SCCmecⅢ型为主,其余为SCCmecⅡ型和SCCmecⅣa型;MRSA的药敏性明显高于MSSA,且不同SCCmec基因型的MRSA耐药性存在明显差异,临床应根据药敏结果合理使用抗菌药物。Objective To explore the genotypes and drug resistance characteristics of methicillin-resistant Staphylococcus aureus(MRSA)isolated from middle ear effusion in patients with chronic suppurative otitis media(CSOM).Methods A total of 120 patients with CSOM admitted to the hospital were enrolled between January 2019 and December 2020.During treatment,middle ear effusion of patients was collected for bacterial isolation.The culture,identification and drug susceptibility tests of isolated pathogens were conducted.The clinical distribution characteristics of pathogens in middle ear effusion of CSOM patients were analyzed.According to infection situations of Staphylococcus aureus,they were divided into MRSA and methicillin-sensitive Staphylococcus aureus(MSSA).The genotypes of MRSA were detected by PCR amplification method.The resistance of different genotypes(MRSA,MSSA)to clinically commonly used antibacterial drugs was detected by Kirby-Bauer(K-B).Results There were 149 strains of pathogens isolated from the 120 samples with middle ear effusion.Among them,there were 45 strains(30.20%)of Gram-negative bacteria,mainly on Pseudomonas aeruginosa(19 strains,12.75%)and Klebsiella pneumoniae(16 strains,10.74%);there were 96 strains(64.43%)of Gram-positive bacteria,mainly on Staphylococcus aureus(73 strains,48.99%);there were 8 strains(5.36%)of fungi,all of which were Candida.In the 73 strains of Staphylococcus aureus,drug sensitivity tests showed that there were 26 strains of MRSA and 47 strains of MSSA.The carrying rate of mecA gene in the 26 strains of MRSA was 100%.The multiple PCR showed that there were 15 strains(57.69%)with type SCCmec II,7(26.92%)strains with type SCCmec III,and 4 strains(15.38%)with type SCCmec IVa.The resistance rates of MRSA to penicillin,oxacillin,gentamicin,levofloxacin,rifampicin and nitrofurantoin were significantly higher than those of MSSA(P<0.05).In MRSA,resistance rates to levofloxacin,ciprofloxacin and moxifloxacin were the highest in SCCmec II,followed by SCCmec III and SCCmec IVa(P<0.05)

关 键 词：慢性化脓性中耳炎 金黄色葡萄球菌 耐甲氧西林金黄色葡萄球菌 基因分型 耐药性 

分 类 号：R446.5[医药卫生—诊断学]