2015—2021年CHINET血液分离菌的分布及耐药性变迁

Distribution and antimicrobial resistance profiles of clinical isolates from blood samples:results from China Antimicrobial Surveillance Network(CHINET)from 2015 to 2021

目的了解2015—2021年CHINET血液标本临床分离菌的分布和耐药性。方法对2015—2021年CHINET 52所医疗机构血液标本临床分离菌进行细菌耐药性分析。结果临床分离153591株血培养阳性的细菌中革兰阳性菌占48.8%,革兰阴性菌占51.2%。前五位的分离菌依次是凝固酶阴性葡萄球菌(28.2%)、大肠埃希菌(20.7%)、克雷伯菌属(13.7%)、肠球菌属(7.2%)、金黄色葡萄球菌(6.6%);男性患者除大肠埃希菌的分离率低于女性外,其他临床分离菌的分离率均高于女性患者。儿童患者肺炎链球菌和沙门菌的分离率高于成年患者。肠杆菌目细菌对抗菌药物的耐药率不尽相同。7年间大肠埃希菌对头孢噻肟、庆大霉素和左氧氟沙星的耐药率高,分别≥58.0%、≥36.8%和≥56.8%;但对碳青霉烯类的耐药率仅≤2.5%。肺炎克雷伯菌对亚胺培南和美罗培南的耐药率较之该菌目中其他细菌的耐药率为高;7年间的耐药率变迁显示分别从2015年的21.4%和19.9%上升至2021年的25.7%和26.6%;但碳青霉烯类对其他肠杆菌目细菌仍然保持良好的抗菌活性,细菌耐药率低。7年间鲍曼不动杆菌对亚胺培南和美罗培南的耐药率呈锯齿形变迁,虽显示呈下降的态势,但2021年仍保持有72.9%和73.2%的耐药率;铜绿假单胞菌对亚胺培南和美罗培南的耐药率呈下降态势,分别由2015年的26.7%和22.9%下降至2021年的18.5%和14.7%。成人和儿童肺炎链球菌青霉素耐药株的检出率分别为1.5%和0.8%。屎肠球菌和粪肠球菌对万古霉素、替考拉宁和利奈唑胺的耐药率均低于3.0%。耐甲氧西林的金黄色葡萄球菌(MRSA)和凝固酶阴性葡萄球菌(MRCNS)的检出率分别为32.1%和81.0%,7年间MRSA的检出率同样显示为锯齿形变化,2021年的检出率28.0%与2015年的28.5%相近。结论2015—2021年CHINET血液标本分离菌以凝固酶阴性葡萄球菌、大肠埃希菌和肺炎克雷伯菌为主,不同年龄和性别的患者主要分离菌分布差异有统计学意义。血液标本主要临床分离菌的耐药率在锯齿形变化中呈现一定缓慢下降,但伴随着新的多重耐药菌的不断检出,提示在临床中应继续对血液标本分离菌进行耐药性监测,为临床合理应用抗菌药物提供准确的耐药监测数据,遏制细菌耐药发生。

Objective To investigate the distribution and antimicrobial resistance of bacterial isolates from blood samples in the hospitals participating in China Antimicrobial Surveillance Network(CHINET)from 2015 to 2021.Methods Bacterial strains isolated from blood samples were collected from 52 medical centers participating in CHINET from 2015 to 2021 for analysis of bacetrial distribution and antimicrobial resistance.Results A total of 153591 isolates were collected,48.8%of which were grampositive bacteria and 51.2%were gram-negative bacteria.The top five bacterial strains were coagulase negative Staphylococcus(28.2%),Escherichia coli(20.7%),Klebsiella(13.7%),Enterococcus(7.2%),and Staphylococcus aureus(6.6%).Compard to female patients,male patients showed lower proportion of E.coli and higher proportions of other bacterial species in all the bacterial isolaets from blood samples.The proportions of Streptococcus pneumoniae and Salmonella in all the bacterial isolaets from blood samples were higher in children compared to adults.Enterobacterales species showed various resistance rates to antimicrobial agents.Overall,≥58.0%,≥36.8%and≥56.8%of E.coli strains were resistant to cefotaxime,gentamicin and levofloxacin respectively over the 7-year period.However,less than 2.5%of the E.coli strains were resistant to carbapenems.K.pneumoniae showed higher resistance rates to imipenem and meropenem than other Enterobacterales species.During the 7-year period,the prevalence of imipenem-resistant and meropenem-resistant K.pneumoniae increased from 21.4%and 19.9%in 2015 to 25.7%and 26.6%in 2021,respectively.However,carbapenems still maintained good antibacterial activity against other Enterobacterales,associaetd with lower resistance rates.In the 7-year period,Acinetobacter baumannii showed a dwonward trend in the resistance rates to imipenem and meropenem,but remained 72.9%and 73.2%respectively in 2021.The prevalence of imipenem-resistant and meropenem-resistant P.aeruginosa decreased from 26.7%and 22.9%in 2015 to 18.5%and 14.7%in 2021,respectively.The prevalence of PRSP was 1.5%in the isolaets from adults and and 0.8%in the isolates from children.Less than 3.0%of the Enterococcus faecium and Enterococcus faecalis strains were resistant to vancomycin,teicolanin,or linezolid.The prevalence of methicillin-resistant S.aureus(MRSA)and coagulase negative Staphylococcus(MRCNS)was 32.1%and 81.0%,respectively.The prevalence of MRSA was relatively stable,28.5%in 2015 and 28.0%in 2021.Conclusions Coagulase negative Staphylococcus,E.coli and K.pneumoniae were the main bacterial species isolated from blood samples in the hospitals participaing in the CHINET from 2015 to 2021.Significant sex and age differences were found in the distribution of bcterial isolates from blood samples.The overall resistance rates of the top bacetrial strains from blood samples to antimicrobial agents showed a downward trend.Ongoing surveillance of antimicrobial resistance for the isolates from blood samples is still essential for prescribing rational antimicrobial therapies and curbing bacterial resistance.