葡萄球菌属的分离及耐药性研究

目的　对 1 974株临床分离的葡萄球菌的耐药性进行研究 ,以观察葡萄球菌属的耐药现状。方法　药敏试验采用纸片扩散法 (K -B法 )。结果　临床分离到的葡萄球菌中 ,MRSA的分离率为 2 0 .8% (66/ 31 7) ,MRCNS的分离率为 66 .9% (1 1 0 9/ 1 657) ,MRSA主要来源于生殖道分泌物、痰、伤口分泌物 ,分别占 2 7.3 % ,2 2 .7% ,1 8.2 % ;血液标本中MRSA和MRCNS分别占总分离数的 0 .2 5 %和 4 .9% ,而MRSA只占 0 .2 5 %。MRSA和MRCNS对红霉素、庆大霉素、氯霉素、克林霉素、环丙沙星、复方磺胺甲恶唑、四环素的耐药率分别为 86 .2 %、47.6 %、50 .8%、61 .3 %、54 .5 %、83 .3 %、66 .1 %和 84.9%、37.5 %、45 .9%、53 .7%、58.2 %、84.9%、67.6 % ;MSCNS中环丙沙星、复方磺胺甲恶唑、四环素、氯霉素的耐药率分别为 33 .0 %、64 .1 %、58.5 %、2 7.8%均高于MSSA的 1 4 .6 %、42 .8%、41 .5 %、1 7.7% ,但对于MSS环丙沙星、庆大霉素、氯霉素、克林霉素有较高的敏感性。结论　重视对葡萄球菌的耐药性监测 ,合理使用抗生素、特别是合理使用糖肽类抗生素是非常必要的。     

头孢西丁纸片法检测mecA基因介导的MRS

目的评价应用头孢西丁纸片扩散法检测mecA基因介导的耐甲氧西林葡萄球菌(MRS)。方法分别用头孢西丁纸片法扩散法、苯唑西林纸片扩散法、苯唑西林琼脂稀释法、VITEK微生物自动分析系统及聚合酶链反应(PCR)mecA基因检测4种方法对MRS进行检测比较,最低抑菌浓度(MIC)测定应用VITEK微生物自动分析系统GPS卡。结果96株葡萄球菌属(金黄色葡萄球菌16株、凝固酶阴性葡萄球菌80株)中苯唑西林纸片法扩散法、苯唑西林琼脂稀释法、VITEK微生物自动分析系统3种方法检出MRS菌株54株(金黄色葡萄球菌2株、凝固酶阴性葡萄球菌52株),而PCR法检出mecA基因48株(金黄色葡萄球菌2株、凝固酶阴性葡萄球菌46株),头孢西丁纸片法扩散法与PCR法一致。结论头孢西丁纸片扩散法与mecA基因检测法高度一致,是筛选和确认mecA基因介导的MRS一种可靠的方法。     

Emerging Infections Program—State Health Department Perspective

The Emerging Infections Program (EIP) is a collaboration between the Centers for Disease Control and Prevention and 10 state health departments working with academic partners to conduct active population-based surveillance and special studies for several emerging infectious disease issues determined to need special attention. The Centers for Disease Control and Prevention funds the 10 EIP sites through cooperative agreements. Our objective was to highlight 1) what being an EIP site has meant for participating health departments and associated academic centers, including accomplishments and challenges, and 2) the synergy between the state and federal levels that has resulted from the collaborative relationship. Sharing these experiences should provide constructive insight to other public health programs and other countries contemplating a collaborative federal–local approach to collective public health challenges.     

两种耐甲氧西林葡萄球菌监测

目的监测上海市区级及社区医院耐甲氧西林金葡菌及耐甲氧西林凝固酶阴性葡萄球菌的流行及耐药现状。方法对二所区级及社区医院从2003年8月～2004年2月的感染标本中分离的378株葡萄球菌进行鉴定和药敏实验。结果对耐甲氧西林金葡菌分离率52．38％，对耐甲氧西林凝固酶阴性葡萄球菌分离率47．62％。二者均为多重耐药球菌，但对利福平均敏感，耐药率分别为0．9％及2．9％。二者均未发现耐万古霉素菌株。结论上海市二所社区医院中耐甲氧西林金葡菌及耐甲氧西林凝固酶阴性葡萄球菌的流行是严重的，其中前者的流行显著高于教学医院，二者均为多重耐药菌株。     

外科住院患者感染耐甲氧西林凝固酶阴性葡萄球菌的耐药基因检测及耐药性分析

目的对南京市外科住院患者感染的耐甲氧西林凝固酶阴性葡萄球菌的耐药相关基因进行检测,以更好地控制病原菌耐药性,减少外科感染。方法从南京市多家医院外科住院患者各类临床标本分离耐甲氧西林凝固酶阴性葡萄球菌70株,经纯培养获单菌落后进行鉴定,并进行药敏试验,然后对耐药基因进行PCR测序,对PCR扩增产物进行电泳检测并记录。结果耐甲氧西林凝固酶阴性葡萄球菌对于头孢噻肟和红霉素100%耐药,对万古霉素耐药率为0,对其他抗菌药物的耐药率大小依次为:左氧氟沙星>诺氟沙星>氨苄西林>妥布霉素>环丙沙星>克林霉素>头孢曲松>庆大霉素>四环素>利福平。PCR检测耐药基因,3株只携带mecA 1种耐药基因。15株携带2种耐药基因,分别为:ermA+mecA、aac(6′)/aph(2′′)+mecA和aph(3′)-III+mecA和tetM+mecA。29株携带3种耐药基因,携带方式分别为:ermA+aac(6′)/aph(2′′)+mecA、aph(3′)-III+ermA+mecA、ermA+tetM+mecA、aac(6′)/aph(2′′)+aph(3′)-III+mecA、aac(6′)/aph(2′′)+tetM+mecA和tetM+aph(3′)-III+mecA。20株携带4种耐药基因,携带方式分别为:aac(6′)/aph(2′′)+tetM+ermA+mecA、aph(3′)-III+tetM+aac(6′)/aph(2′′)+mecA、aph(3′)-III+tetM+ermA+mecA和aph(3′)-III+aac(6′)/aph(2′′)+ermA+mecA。有3株携带5种耐药基因,即ermA+aph(3′)-III+tetM+aac(6′)/aph(2′′)+mecA。结论耐甲氧西林凝固酶阴性葡萄球菌对常用抗菌药物的耐药性普遍较高,5种耐药基因在菌株中出现的频率不同,但所有病原菌都存在mecA基因,因而该菌的耐药性可能与mecA基因有关。     

院内传播耐甲氧西林葡萄球菌的DNA指纹图谱分析

目的对医院内传播的12株耐甲氧西林葡萄球菌（MRS）作DNA指纹图谱分析，寻找传播途径，控制院内感染。方法纸片琼脂扩散（K—B）法检测细菌耐药性，聚合酶链反应（PCR）法检测mecA基因携带情况，采用ERIC—PCR作DNA指纹图谱分析。结果12株分离菌耐药表型和基因型相同，均对万古霉素和替考拉宁敏感，对其他13种抗菌药物耐药，mecA基因全部阳性。12株不同来源菌株的DNA同源性达100％。患者家属及医护人员的手和病房物体表面被污染情况严重。结论MRS对抗菌药物呈多重耐药性。患者家属及医护人员手部卫生意识薄弱，这是引起MRS医院内传播的主要原因。应加强监控．防止MRS的医院内感染。     

苯唑西林和头孢西丁纸片扩散法现行耐药折点判断凝固酶阴性葡萄球菌甲氧西林耐药性的评价

目的 评价苯唑西林和头孢西丁纸片扩散法现行耐药折点在判断凝固酶阴性葡萄球菌（CNS）甲氧西林耐药性中的准确性。方法 苯唑西林（1μg）和头孢西丁（30μg）纸片扩散法测定149株临床分离的CNS对甲氧西林的耐药性，量取两种纸片的抑菌环直径。对苯唑西林组分别以≤14mm、≤15mm、≤16mm、≤17mm（CLSI／NCCLS2004标准）为耐药折点，对头孢西丁组分别以≤21mm、22mm、≤23mm、≤24mm（CLSI／NCCLS2004年标准）为耐药折点，与mecA基因检测结果比较，评价两种纸片扩散法在各折点对耐甲氧西林CNS判断的敏感性和特异性。结果 与mecA基因检测结果比较，苯唑西林纸片扩散法在不同的耐药折点判断耐甲氧西林表皮葡萄球菌的敏感性分别为52．3％、75．0％、90．9％、100％，特异性都为100％，判断耐甲氧西林非表皮葡萄球菌CNS的敏感性分别为66．7％、79．0％、90．1％、97．5％，特异性分别为100％、100％、100％、94．4％；头孢西丁纸片扩散法在不同耐药折点判断耐甲氧西林表皮葡萄球菌的敏感性分别为45．5％、70．1％、90．9％、100％，特异性都为100％，判断耐甲氧西林非表皮葡萄球菌CNS的敏感性分别为83．6％、91．8％、97．3％、100％，特异性都为100％。结论 苯唑西林和头孢西丁纸片扩散法检测耐甲氧西林CNS的现行耐药折点标准在判断表皮葡萄球菌和非表皮葡萄球菌CNS的甲氧西林耐药性中都有很高的敏感性和特异性，适用于CNS对甲氧西林耐药性的判断。对于非表皮葡萄球菌CNS，头孢西丁纸片扩散法较苯唑西林纸片扩散法结果更可靠。     

The oral microbiota of children undergoing liver transplantation

This study investigated the oral microbiota of children undergoing liver transplantation. Oral swabs were taken using a standardized procedure from 27 children before liver transplantation and at 3 and 100 days post-transplantation and from 27 healthy controls at baseline and 90 days. Viridans streptococci, yeasts, staphylococci, enterococci and Enterobacteriaceae were enumerated and identified using conventional techniques. The oral microbiota of the patients changed significantly immediately post-transplantation, but by the final examination, it had returned to baseline levels. The oral microbiota of the controls did not change significantly. The numbers and proportions of Streptococcus salivarius, Streptococcus sanguis and Streptococcus gordonii as percentages of the total streptococcal counts and of the total anaerobic counts decreased significantly 3 days post-transplantation (P < or = 0.006). There were no significant changes in the numbers and proportions of Streptococcus oralis and Streptococcus mitis isolated pre- and post-transplantation. The isolation frequencies and numbers of yeasts were significantly higher in patients than controls. Staphylococci were isolated in low numbers from all children. Enterococci and Enterobacteriaceae were isolated infrequently from patients.