呼吸重症监护室耐甲氧西林金黄色葡萄球菌分子流行病学调查

目的 调查呼吸重症监护室(RICU)病房耐甲氧西林金黄色葡萄球菌(MRSA)来源、分子分型及药敏,并提供治疗建议.方法 选取成都医学院第一附属医院RICU病房2017年1月至2020年12月从43例病人痰标本、肺泡灌洗液、血液、尿液标本等分离出的52株MRSA,统计标本来源.采用琼脂稀释法进行药敏试验;采用多位点序列分...

Molecular epidemiology investigations of methicillin-resistant Staphylococcus aureus in RICU

Objective To investigate the source,genotyping,and drug resistance of methicillin-resistant Staphylococcus aureus(MRSA)isolated from the respiratory intensive care unit(RICU),and provide treatment recommendations.Methods A total of 52 MASA isolates were collected from sputum,bronchoalveolar lavage fluid(BALF),blood,and urine specimens in 43 patients treated in RICU from January 2017 to December 2020,and specimen originswere counted.A susceptibility test was carried out using the agar dilution method.Multiple locus sequence typing(MLST)and the SCCmec genotyping method were used to genotyping those isolated MRSA.Results More than 50%of MRSA were isolated from the respiratory system,followed by blood,pleural drainage liquid,skin and soft tissue,urine,and abdominal drainage liquid.Antimicrobial susceptibility testing results showed MRSA were completely resistant to oxacillin and cefazolin,the resistance rate to erythromycin was as high as 84.62%,and the resistance rate to clindamycin,tetracycline,and levofloxacin were 48.08%,28.85%,and 32.69%,respectively.Furthermore,the resistance rate to moxifloxacin,trimethoprim/sulfamethoxazole,and gentamycin were 17.31%,13.46%,and 15.38%,respectively.Most notably,there was no resistance to linezolid,tigecycline,and vancomycin.In addition,there were 13 MLST types in 52 MRSA strains,mainly ST59(21 strains)and ST5(14 strains),and a total of 5 types of SCCmec were identified,mainly including type IV(36 strains)and type III(10 strains).Conclusion MRSA in RICU is mainly from the respiratory system,and the resistance rate to commonly used antibiotics is very high.The selection of treatment strategies can be guided according to the typing test results and the distribution characteristics of drug resistance.