皮肤科耐甲氧西林金黄色葡萄球菌临床分布特点及耐药性分析

Clinical Distribution and Drug Resistance of the Methicillin-Resistant Staphylococcus Aureus

目的探讨皮肤软组织分泌物中耐甲氧西林金黄色葡萄球菌(MRSA)的临床分布特点及耐药性分析,为皮肤科防治MRSA提供理论依据。方法回顾性分析2015年1月-2021年9月本院皮肤性病科皮肤软组织创面分离培养出的金黄色葡萄球菌和MRSA。采用法国生物梅里埃公司的全自动微生物分析鉴定仪(VITEK-2 Compact)鉴定菌种,应用该仪器配套的药敏卡进行微量肉汤稀释法检测菌株的MIC。药物敏感结果判读按照CLSI M100标准执行。结果在2015年1月-2021年9月期间,分离出899株金黄色葡萄球菌,其中282株(检出率31.37%)为MRSA,由201株社区获得性MRSA(CA-MRSA)和81株医院感染性MRSA(HA-MRSA)组成。CA-MRSA在总MRSA感染中的平均检出率为71.28%(201/282),为主要感染菌,其检出率逐年升高;与CA-MRSA感染患者相比,HA-MRSA感染患者年龄明显偏大(P<0.001),且其感染率逐年升高(P=0.035),但其在性别上没有男女差异;抗生素敏感性方面,HA-MRSA和CA-MRSA对万古霉素、替考拉宁、替加环素、利奈唑胺及达托霉素基本上均敏感(98.77%~100.00%),发现1株CA-MRSA对利奈唑胺耐药,1株HA-MRSA对万古霉素中介;两者对克林霉素、红霉素的敏感性很低(3.70%~19.40%),对苄星青霉素完全耐药。结论MRSA感染率在逐年上升,CA-MRSA是皮肤软组织感染的主要多重耐药菌,MRSA的医院内感染亦逐渐增加。万古霉素等仍然是覆盖MRSA常用有效的药物,皮肤科医师应该要掌握这一流行病学特征,更好地在临床上防治MRSA。

Objective To characterize the patient demographics,clinical features,and antibiotic susceptibility of skin and soft tissue infections caused by methicillin-resistant Staphylococcus aureus(MRSA).Methods Our retrospective analysis included the patients(n=899)with culture-proven S.aureus skin and soft tissue infections who visited the Dermatology Department of the First Affiliated Hospital of Guangxi Medical University,from January 2015 to September 2021.The strains were identified by the automatic microbiological analysis and identification instrument(VITEK-2 Compact),and the minimal inhibitory concentration(MIC)of the strains was detected by the micro-broth release method using the drug susceptibility card matched with the instrument.The interpretation of drug sensitivity results was performed following the CLSI M100 standard.Results From January 2015 to September 2021,899 strains of Staphylococcus aureus were isolated,of which 282 strains were MRSA(detection rate 31.37%),and 201 strains of community-acquired MRSA(CA-MRSA)and 81 strains of hospital infectious MRSA(HA-MRSA).CA-MRSA was the most frequently detected strain,with the detection rate increasing yearly.The average detection rate of CA-MRSA in total MRSA infections was 71.28%(201/282).Moreover,the infection rate of the HA-MRSA increased yearly(P=0.035),similarly in men and women.Compared with CA-MRSA-infected patients,HA-MRSA-infected patients were significantly older(P<0.001).HA-MRSA and CA-MRSA were sensitive to vancomycin,teicoplanin,tigecycline,linezolid and daptomycin(98.77%-100.00%).We found one strain of CA-MRSA resistant to linezolid and one strain of HA-MRSA partially susceptible to vancomycin;however,CA-MRSA and HA-MRSA had low susceptibility to clindamycin and erythromycin(3.70%-19.40%)and were utterly resistant to benzathine penicillin.Conclusion The prevalence of MRSA infections is increasing yearly.CA-MRSA is the main pathogen of skin and soft tissue.Vancomycin is still an appropriate option for MRSA.Dermatologists should be aware of the current epidemiologic situation.