摘要
目的调查复旦大学附属中山医院（中山医院）异质性万古霉素中介的金黄色葡萄球菌（hVISA）的发生率，了解hVISA菌群对新型抗生素的敏感性，研究下呼吸道hVISA感染的危险因素和影响病死率的相关因素。方法收集2008年1月至2010年11月中山医院临床分离的甲氧西林耐药的金黄色葡萄球菌（MRSA）菌株，采用脑心浸出液琼脂（BHIA）筛选平板和宏量Etest试条检测法（macroEtest，MET）进行hVISA的筛选，改良菌群分析策略一曲线下面积（PAP—AUC）确证hVISA。肉汤稀释法测定MRSA对万古霉素、替考拉宁和利奈唑胺的最小抑菌浓度（MIC），用SPSSl6．0比较hVISA和万古霉素敏感的金黄色葡萄球菌（VSSA）在不同MIC区间的分布差异。通过病例调查表收集筛选的hVISA病例和VSSA组的临床信息，使用t检验、Mann—Whitney检验、x2检验及Fisher精确检验进行相关危险因素。结果从457株MRSA菌株中经含5mg／L替考拉宁的BHIA（BHIA5T）、含6mg／L万古霉素的BHIA（BHIA6V）法筛选的hVISA为105株（23．0％），MET法筛选出23株hVISA（5．0％），PAP—AUC法确证的hVISA为21株（4．6％）。hVISA对万古霉素和利奈唑胺均敏感，hVISA和VSSA对万古霉素的MIC分别为（1．76±0．16）mg／L和（1．09±0．07）mg／L（P〈0．01），hVISA和VSSA在不同MIC区间的分布差异无统计学意义（P〉0．05）。单因素分析发现，hVISA组合并慢性阻塞性肺疾病者（5／11）明显高于VSSA组（14．3％，P〈0．05），但未发现hVISA感染与临床病死率相关。结论中山医院hVISA的总体发生率为4．6％，血标本中hVISA的发生率高达12．5％。hVISA对万古霉素和利奈唑胺均为敏感，但hVISA的万古霉素MIC高于VSSA者。下呼吸道内发生hVISA感染与慢性阻塞性肺疾病可能有关。
Objectives To investigate the prevalence of heterogeneous vancomycin intermediate Staphylococcus aureus（ hVISA ） and the sensitivity of hVISA to novel antibiotics, and to explore the risk factors and infection attributable mortality associated with hVISA infection. Methods A total of 456 methieillin resistant Staphylococcus aureu~ （MRSA） isolates were isolated in Zhongshan Hospital from January, 2008 to November, 2010. All MRSA isolates were investigated for hVISA by two agar screening methods BHIAST （ brain-heart infusion containing teicoplanin 5 mg/L ） or BHIA6V （ brain-heart infusion containing vancomyein 6 rag/L） ,as well as macroEtest method（MET）. Possible hVISA isolates were tested by modified population analysis profile-area under the curve （PAP-AUC）. The minimal inhibitory concentrations（MICs） of vancomycin, teicoplanin and linezolid were determined by microbroth dilution as recommended by Clinical Laboratory Standards Institute（CLS1）. The contribution difference between hVISA and vancomycin susceptible Staphylococcus aureus （VSSA） in different MIC range was compared. A retrospective case-control study of the patients with hVISA infection or VSSA infection was carried out and statistical analysis was performed using t test, Mann-Whitney test, X2 test and Fisher exact test. Results A total of 105 isolates of hVISA were screened by BHIA5T and BHIA6V （23.0%） with other 23 isolates by MET（5.0% ） and 21 by PAP-AUC（4. 6% ）. All isolates were 100% sensitive to vancomycin,teicoplanin and linezolid. The vaneomycin MIC[ （ 1.76 ＋ 0. 16 ）mg/Ll in hVISA group was significantly higher than that in VSSA group [ （ 1.09 -＋ 0. 07） rag/L, P 〈 0. 01 J, which was a potential risk factor for hVISA infection. The retrospective study showed chronic obstructive pulmonary disease（COPD） was also a risk factor for hVISA infection of the lower respiratory tract. No significant difference in infection attributable mortality was showed between the hVISA group and the VSSA group. Conclusions The overall prevalence of hVISA in Zhongshan Hospital is estimated as 4. 6%, while the prevalence of hVISA isolated from blood is as high as 12. 5%. All isolates are 100% sensitive to vaneomycin and linezolid. COPD is a risk factor for hVISA infection of the lower respiratory tract.
出处
《中华内科杂志》
CAS
CSCD
北大核心
2013年第4期318-322,共5页
Chinese Journal of Internal Medicine
基金
上海市重点学科建设项目资助（B115）
