【作者】 孟晓洁；

【导师】 李仲兴；

【作者基本信息】 河北医科大学 ， 临床检验诊断学， 2004， 硕士

【摘要】 目的：随着介入性诊疗技术的广泛应用，由凝固酶阴性葡萄球菌（CNS）引起的各种导管相关性感染等机会感染逐渐增多。目前CNS引起的院内感染在革兰阳性球菌中占首位，已经成为临床主要机会致病菌。虽然CNS已引起了国内外的广泛关注，但很多报告至今仍将除表皮葡萄球菌以外的CNS作为一组致病菌笼统介绍，而不同种别CNS因其生物学特性、引起疾病和对抗生素的敏感性不同，所以其诊断和治疗也不相同，因此必须将CNS各种别鉴定至种的水平，从而为临床诊断和治疗提供准确、可靠的依据。方法：①根据Bergey’s Manual of determintive Bacteriology（1994年，第9版）以及Manual for Clinical Microbiology（1997年，第7版）对临床分离的224株CNS进行菌株鉴定，并经API复核鉴定结果；用nitrocefin对试验菌株进行β-内酰胺酶测定；采用NCCLS推荐的二倍琼脂稀释法检测耐甲氧西林CNS。②以ATCC 29213为质控菌株，采用NCCLS推荐的二倍琼脂稀释法测定23种抗菌药物对100株溶血葡萄球菌、里昂葡萄球菌等CNS的最低抑菌浓度（MIC）；③采用新的中药抑菌试验方法，对中药五倍子进行定量抗菌试验。结果：①经鉴定，从临床标本分离的224株CNS中共分离出表皮葡萄球菌、溶血葡萄球菌、里昂葡萄球菌、人葡<WP=4>萄球菌、耳葡萄球菌等12个种别。其中表皮葡萄球菌124株，占55.36%；溶血葡萄球菌42株，占18.75%；里昂葡萄球菌14株，占6.25%；人葡萄球菌9株，占4.02%；耳葡萄球菌5株，占2.23%；腐生葡萄球菌4株，占1.79%；头状葡萄球菌4株，占1.79%；松鼠葡萄球菌4株，占1.79%；瓦氏葡萄球菌3株，占1.34%；产色葡萄球菌3株，占1.34%；模仿葡萄球菌3株，占1.34%；木糖葡萄球菌2株，占0.9%；未定种7株，占3.1%。②经nitrocefin测定，100株溶血葡萄球菌、里昂葡萄球菌等CNS共79株产β-内酰胺酶，产酶率为79%。③100株溶血葡萄球菌等CNS分离出耐甲氧西林CNS 55株，占55%。④100株溶血葡萄球菌、里昂葡萄球菌等CNS对23种抗生素的药敏测试结果表明替考拉宁、万古霉素、米诺环素、多西环素、链霉素对42株溶血葡萄球菌抗菌效果最好，头孢硫脒对溶血葡萄球菌抑菌效果也较好；替考拉宁、万古霉素、米诺环素、庆大霉素对里昂葡萄球菌的抗菌效果最好；万古霉素、替考拉宁、米诺环素、庆大霉素、利福平对人葡萄球菌、耳葡萄球菌等CNS抗菌效果最好。不耐酶青霉素类、大环内酯类抗生素对100株溶血葡萄球菌等CNS抗菌效果均不理想。⑤五倍子对溶血葡萄球菌、里昂葡萄球菌等CNS的抗菌效果较好，五倍子水煎剂对100株凝固酶阴性葡萄球菌的MIC50为0.051mg/ml，MIC90为0.203mg/ml，五倍子乙醇提取物对100株CNS的MIC50为0.036mg/ml，MIC90则为0.288mg/ml，说明五倍子是一种具有研究开发价值的抗感染中药。结论：经我们对从临床分离出的100株溶血、里昂葡萄球菌等CNS，采用手工及API Staph系统等鉴定，在224株<WP=5>CNS中，鉴定出12个种别，它们的生物学特性、感染类型不同、其对抗生素敏感和耐药谱型也不同，如腐生葡萄球菌是女性尿道感染的主要致病菌，里昂葡萄球菌则主要引起严重的感染性心内膜炎，而溶血葡萄球菌多见于导管相关性菌血症感染。在对抗生素的敏感和耐药谱型中，头孢硫脒对溶血葡萄球菌包括甲氧西林耐药溶血葡萄球菌的抗菌活性很强，可以用于溶血葡萄球菌引起的感染治疗，但对里昂葡萄球菌、耳葡萄球菌、人葡萄球菌等CNS效果较差。多西环素对耳葡萄球菌、腐生葡萄球菌等CNS的抗菌活性也略逊于其它CNS，所以，临床实验室应通过各种手段和方法将临床分离的CNS准确地鉴定至种的水平，从而为临床诊治此类感染提供有针对性的实验室数据。我们还通过中药抗菌试验发现五倍子水煎剂和乙醇提取物对CNS均有较好的体外抗菌效果，如能进一步研究，可望开发出治疗此类感染的新的抗菌药物。更多还原

【Abstract】 objectives：With the wildly development of interventional therapy, especially the opportunistic infection which caused by coagulase-negative staphylococci (CNS) has increased dramaticaly in recent years. Currently, CNS has became one of the most important cause of nosocomial infection and has been the primacy in gram-positive cocci. Although they are now considered significant nosocomial pathogens complicating central venous catehters, prosthetic heart valves ect. While data on the clinical significance of other CNS expect Staphylococcus epidermidis are limited, and few are available for them. Every species of CNS has its own characteristics, cause both different infections and susceptibility to antibiotics are different, accordingly, the diagnosis and therapy of every species is different too. In order to provide more exact and reliable data for diagnosis and therapy, it is necessary to identify all CNS to the level of species.Methods: ①identify CNS come from clinical samples flowing Bergey’s Manual of determintive Bacteriology(1994, 9th) and Manual for Clinical Microbiology(1997，7th), and re-examination the result by API Staph ; determine strains <WP=7>which products bate-lactam enzyme by nitrocefin ; select methicilline-resistant CNS by agar dilution methods. ②determine the MIC of 23 kinds of antibiotics against all the 100 strains of S.haemolyticus ect. CNS by agar dilution methods, the control strains is ATCC 29213. ③do quantitive antibacterial test of Galla chinensis in M-H agar using new methods of antibacterial experiment of traditional Chinese medicine.Results: ①there are 124 strains S. epidermidis (55.36%), 42 strains S. hemolyticus (18.75%), 14 strains S.lugdunensis (6.25%), 9 strains S.hominis (4.02%), 5 strains S.auricularis (2.23%), 4 strains S.saprophyticus (1.79%), 4 strains S.capitis (1.79%), 4 strains S. sciuri (1.79%), 3 strains S.warneri (1.34%), 3 strains S.chromogenes (1.34%), 3 strains S.simulans (1.34%), 2 strains S.xylosus (0.9%), 7 strains not identified (3.1%). ②79 strains of 100 Strains S. haemolyticus ect. CNS which produced bata-lactam enzyme are determined by nitrocefin, the ratio is 79%. ③there are 55 methicilline-resistant strains from 100 strains of S. haemolyticus ect. CNS, the ratio is 55%. ④the results of 23 kinds of antibcterial susceptibility test show that the antibaterial efficiency of teicoplanin, vancomycin, minocycline, doxycycline, and streptomycine against 42 strains of S. haemolyticus are excellent; the antibaterial efficiency of <WP=8>teicoplanin, vancomycin, minocycline, and gentamicin against 14 strains of S.lugdunensis are excellent; the antibaterial efficiency of vancomycin, teicoplanin, minocycline, gentamicin, and rifampicin against 9 strains of S.hominis and 35 strains of S.auricularis ect. CNS are excellent. ⑤the results of antibacterial test of Galla chinensis show that the antibacterial efficiency of Galla chinenesis decoction is better. Its MIC50, MIC90 against 100 strains of CNS are 0.051mg/ml, and 0.203mg/ml respectively. The antibacterial activity of Galla chinensis alcohol extractant against 100 strains of CNS is better too, the MIC50, MIC90 are 0.036mg/ml, and 0.288mg/ml, respcetively.Conclusions: In this research, we use the identified methods by hand and API Staph system ect.to identify CNS which come from clinical sample, we get 12 species from 224 strains of CNS. These CNS has different characteristics, lead to different infections, and have different antibiotic susceptibility, for example, S.saprophyticus is an important pathogen of women urinary tract, S.lugdunensis has been shown to be associated with serious native valve endocarditis, and the catheter related infcetion are often caused by S. hemolyticus. As far as the antibacterial activity, the antibiotic efficiency of Cefathiamidine <WP=9>against S. hemolyticus is better, but inferior to other CNS, the antibiotic efficiency of doxycycline against S.auricularis and S.saprophyticus is less than others. So the clinical laboratory must identify all CNS clearly, in order t更多还原