2012年中国16家医院革兰阳性球菌耐药监测研究

A surveillance study of antimicrobial resistance of gram-positive cocci strains isolated from 16 teach- ing hospitals in China in 2012

目的调查2012年我国16家医院革兰阳性球菌临床分离株的耐药率。方法收集2012年6至12月16家教学医院临床分离的1790株非重复革兰阳性球菌。采用琼脂稀释法测定抗菌药物的MIC，回顾性研究不同病原菌对临床常用抗菌药物的耐药率，采用一般x^2检验比较不同年龄组中耐甲氧西林金黄色葡萄球菌（MRSA）和耐青霉素肺炎链球菌（PRSP）的发生率。结果MRSA和耐甲氧西林凝固酶阴性葡萄球菌（MRCoNS）的发生率分别为43．6％（264／605）和75．7％（227／300），不同地区MRSA发生率为20．5％～60．9％，不同标本中MRSA发生率为：呼吸道标本54．4％（106／195）、血液标本43．6％（58／133）、伤口组织及脓液标本29．8％（56／188），老年组中MRSA发生率（53．9％，110／204）高于成人组（41．4％，149／360）（P〈0．05）。MRSA对氯霉素和复方新诺明的敏感率分别为92．4％（244／264）和89．8％（237／264），对庆大霉素、红霉素、克林霉素、四环素、利福平和喹诺酮类药物的敏感率为12．5％-51．9％，发现1株对万古霉素中介的金黄色葡萄球菌（VISA），万古霉素MIC值为3μg/ml。未发现对替考拉宁、万古霉素、利奈唑胺和达托霉素耐药的金黄色葡萄球菌。PRSP在幼儿组中的发生率为61．2％（49／80），高于成人组的40．2％（90／224）（P〈0．05）。肺炎链球菌对红霉素和克林霉素的耐药率分别为93．6％（292／312）和86．2％（269／312）。各群B-溶血链球菌对青霉素均敏感，但对红霉素、克林霉素、四环素的耐药率均超过60％。发现4株万古霉素耐药肠球菌（VRE）。粪肠球菌和屎肠球菌均对达托霉素和替加环素敏感，对利奈唑胺的敏感率分别为96．9％（157／162）和99．3％（150／151），对高浓度庆大霉素的耐药率分别为51．9％（84／162）和61．6％（93／151），粪肠球菌对氯霉素和四环素的敏感率低于屎肠球菌，但对其他所测试抗菌药物均有较高的敏感率。结论不同地区、不同年龄组间革兰阳性球菌的耐药率有所差异；替考拉宁、万古霉素、利奈唑胺、替加环素和达托霉素对革兰阳性球菌具有很好的抗菌活性。

Objective To investigate antimicrobial resistance among gram-positive cocci strains in China in 2012. Methods From June 2012 to December 2012, 1790 consecutive and non-repetitive gram- positive cocci strains were collected from 16 teaching hospitals. The minimal inhibitory concentrations （MICs） of antibacterial drugs were determined by agar dilution method. A retrospective study was conducted on the rates of resistance to antimicrobial agents. Data was analyzed using chi-square test. Results The prevalence of methicillin-resistant Staphylococcus aureus （MRSA） and methicillin-resistant coagulase-negative Staphylococci （MRCoNS）were 43.6% （264/605）and 75.7% （227/300）, respectively. The prevalence of MRSA ranged from 20.5% to 60.9% in different regions. About 54.4% （106/195） of Staphylococcus aureus from respiratory tract specimens, 43.6% （58/133） of Staphylococcus aureus from blood samples, and 29.8% （56/188） of Staphylococcus aureus from wound and pus were resistant to methicillin. The preva- lence of MRSA in eider patient group （53.9%, 110/204） was higher than that in the younger aduh patients （41.4%, 149/360） （P〈0.05）. The susceptible rates of MRSA to chloramphenicol and SXT were 92.4% （244/264） and 89.8% （237/264）, respectively. Susceptibility of MRSA to gentamycin, erythromycin, clindamycin, tetracyclines, rifampicin and quinolones were ranged from 12.5% to 51.9%. One vancomy- cin-intermediate Staphylococcus aureus （VISA） was found in this study. All Staphylococci isolates were sus- ceptible to teicoplanin, vancomycin, hnezolid, daptomycin and tigecychne. The prevalence of penicillin-re- sistant Streptococcus pneumoniae （PRSP） in children below 3 years-old （61.2%, 49/80） was higher than that in adult patients （40.2% ,90/224） （P〈O. 05）. About 93.6% （292/312） and 86.2% （269/312） of S. pneumonia were resistant to erythromycin and clindamycin, respectively. Penicillin still showed a very high activity against Streptococcus spp. F-Hemolytic group, but more than 60% of Streptococcus spp. 13-he- molytic group were resistant to erythromycin, clindamycin and tetracyclines. Four vancomycin-resistant en- terococcus （VRE） strains were found in this study. All Enterococcus isolates were susceptible to daptomycin and tigecycline, and 96.9% （157/162） of E. faecalis and 99.3 % （ 150/151 ） of E. faecium were suscepti- ble to line aid. About 51.9% （84/162） of E. faecalis and 61.6% （93/151） of E. faecium were resistant to high concentration gentamycin. The susceptibility of E. faecalis to all antibiotics except ehloramphenicol and tetracycline was higher than that of E. faecium. Conclusion The rates of antimicrobial resistanee of Gram-positive coeei are different among strains isolated from different age groups or regions. Teicoplanin, vancomycin, linezolid, tigecyeline and daptomycin showed very high activity against Gram-positive cocci.