水产病原菌抗菌药物敏感试验标准化探讨*

病原菌药物敏感试验是临床微生物学研究的重要手段,相比人类和兽医临床,国内外水产养殖中细菌性病原的药敏试验还未有公认的标准化参考方法。概括近几年国外对水产病原菌药敏试验标准化方法建立的研究进展,探讨了试验中关键因子的影响,指出我国水产药敏试验中存在的不足及对未来发展提出展望。     

抑菌生的药物敏感试验

本文检测了BS_(224)菌对21种抗生素的药敏情况。结果,除对林可霉素、链霉素呈中度敏感外,其余均敏感,说明BS_(224)菌是抗生素敏感菌。     

真菌药物敏感性试验的现状

随着真菌感染的增加及耐药现象的出现,借助真菌药敏结果合理选择抗真菌药物已受到临床医生的重视,以往真菌药敏试验普遍存在的问题是缺乏统一,标准和规范的方法,有关真菌标准化体外药敏试验方法的建立,以及一些更为简便,改良方法的发展,使各实验室能够为临床提供具有可比性准确的药敏结果,为制定敏感和耐药标准提供科学依据。本文综述了真菌药敏试验的标准化问题及其与临床的相关性。     

药物敏感试验药片法研究

药敏药片对国际三株标准菌试验,抑菌圈直径范围均符合判定标准。与进口药敏药片符合率为１００％。与药敏纸片片间差比较试验,药片抑菌圈＝１～２ｍｍ,精密度高,符合国际要求,而纸片抑菌圈＝９～１３ｍｍ,均匀度检测明显不合格。药片变异系数ＣＶ＝１．３１～２．９２,纸片ＣＶ＝１４．７８～２１．６７表明药片变量离散度小,片间差很小;而纸片变量离散度明显大,故纸片片间差很大。     

痰液标本病原菌培养及其药敏分析

目的 探讨东莞地区政标本２的常见病原菌及其对抗生素的敏感性。方法 参照《全国临床检验操作规程》处理下呼吸道痰液标本２,分离培养和鉴定菌株。用Ｋｉｒｂｙ－Ｂａｕｅｒ（Ｋ－Ｂ）法进行药数测定。结果 ９３全怀标本共检出９８株菌,其中甘兰阴性杆菌居多共６３株,占６４％（其中又以非发本报菌居多共４１株,占４１．８％）,球菌仅有３１株,占３１．６％。革兰阴性杆菌对泰能量敏感,丁胺卡那霉素次之,葡萄球菌只泰能较     

抗真菌药物敏感性试验方法的新进展

真菌感染,尤其是免疫低下患者机会性真菌感染发病率的不断上升使真菌病的治疗面临着严峻的挑战,各种新的抗真菌药物纷纷涌现。临床实践中,人们需要规范快速、易于应用的药敏试验来指导用药和判断预后,抗真菌药物敏感性试验在真菌感染的治疗中起着重要作用。     

血培养中病原菌分布及药敏调查分析

目的了解血培养中病原菌的分布及药敏情况,供临床借鉴。方法对中山大学附属第三医院血培养标本中所分离到的细菌及药敏结果进行统计分析。结果从血培养标本中分离到细菌239株,其中其中革兰阴性杆菌(G-b)131株,占52.6%,革兰阳性球菌(G+c)99株,占39.8%(99/236),真菌占6.8%,大肠埃希菌和肺炎克雷伯菌产ESBLs菌检出率分别是54.2%和48.6%,只对亚胺培南、特治星和阿米卡星敏感,敏感率超过85%,G+c中,耐甲氧西林金黄色葡萄球菌(MRSA)和耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)的检出率分别是42.9%和89.2%,只对万古霉素敏感(100%),检出的肠球菌已出现对万古霉素耐药。结论血培养分离的病原菌分布复杂,产ESBLs菌和MRS菌株检出率高,临床应重视血培养检测结果.合理用药。     

294株白念珠菌药物敏感试验及耐药性分析

近年来,随着临床使用大量抗生素、免疫抑制剂和糖皮质激素治疗严重感染、肿瘤及自身免疫病,人体菌群失调和真菌感染发生率持续升高.同时,抗真菌药物的频繁应用亦造成真菌耐药性日益增多,真菌感染成为医院感染的主要病原体之一.真菌感染中以白念珠菌（Candida albicans）比例最高,本文对本院2012年1～12月送检的临床标本常规培养分离,共分离的白念珠菌294株,其药物敏感试验及耐药性分析如下.     

慢性化脓性中耳炎患者耳道分泌物的病原菌检测及药物敏感性分析

目的 分析慢性化脓性中耳炎（CSOM）患者耳道分泌物的病原菌分布及其药敏情况,为临床合理应用抗菌药物提供参考。方法 收集浙江省立同德医院100例（116耳）CSOM患者耳道分泌物标本进行常规病原菌分离、鉴定及药敏试验。结果 116耳中有97耳培养出病原菌,检出率为83.6%。共检出病原菌103株,其中革兰阳性菌占53.4%（55/103）,革兰阴性菌占41.7%（43/103）,真菌占4.9%（5/103）。金黄色葡萄球菌和表皮葡萄球菌对青霉素和磺胺甲恶唑/甲氧苄啶耐药性较高,对利福平和莫西沙星敏感性较高,对呋喃妥因和万古霉素完全敏感。铜绿假单胞菌和肺炎克雷伯菌对头孢唑啉、氨苄西林、头孢吡肟、头孢曲松、哌拉西林/舒巴坦耐药性均较高,对妥布霉素、氨曲南、哌拉西林/他唑巴坦敏感性较高,对阿米卡星、美罗培南及亚胺培南完全敏感。真菌对氟胞嘧啶、两性霉素B及制霉菌素均敏感,而对酮康唑和氟康唑有一定的耐药性。结论 CSOM患者耳道分泌物中病原菌以金黄色葡萄球菌、表皮葡萄球菌、铜绿假单胞菌及肺炎克雷伯菌为主,这4种病原菌对多数常用抗菌药物有较强的耐药性,治疗时需根据细菌培养及药敏分析结果合理选用抗菌药物。     

MALDI-TOFMS快速检测病原菌耐药性的应用进展

基质辅助激光解析电离飞行时间质谱(MALDI-TOFMS)技术已经在病原菌鉴定上取得了非常理想的效果,具有流程简单、准确快速、高通量等优点,被越来越广泛地应用于临床微生物实验室中.作为一种快速、简便且经济的方法,MALDI-TOFMS在病原菌耐药性的临床检测方面也展现出巨大的潜力,是目前临床微生物学领域的一大研究热点....     

解脲脲原体生物膜药敏检测方法的研究进展

解脲脲原体（Uu）生物膜的培养及药敏检测技术是继支原体体外游离药敏试验之后,探讨Uu耐药水平与耐药机制的又一重要手段。然而由于支原体生长的生物学特性,使实验中需要多次更换培养基,增加了污染的概率。培养过程中的杂菌污染由此成为决定Uu生物膜实验成功与否的一大问题。本文将对解脲脲原体生物膜的培养与药敏检测技术,从检测方法、常见污染途径与解决策略3个方面展开,对相关文献作一综述。     

沙井地区384例支原体药敏试验结果及分析

目的:了解本地区社区感染支原体的药物敏感情况。方法:对门诊标本培养出的384例支原体进行药敏试验(微量肉汤法)。结果:Uu对交沙霉素、克拉霉素及罗红霉素敏感性高,敏感率分别为98%、94%及93%;对环丙沙星、大观霉素耐药性高,敏感率分别为8%及11%。Mh对交沙霉素敏感率为89%、对大现霉素、多西环素、美满霉素的敏感率均为78%;对罗红霉素、红霉素耐药性高,敏感率分别为0%及11%。Uu合并Mh对交沙霉素、多西环素、美满霉素敏感性高,敏感率分别为85%、73%及69%,对红霉素、克拉霉素、大观霉素的敏感性均为0%,对罗红霉素、阿奇霉素、环丙沙星的敏感率均为4%。结论:支原体的敏感性存在时空差异,且不同类型的支原体对抗菌素的敏感性是不同的,应采用实验室结果而非经验指导用药。     

圈养林麝脓肿病病原菌分离鉴定及药敏分析

目的 确定林麝化脓性疾病的主要病原菌,寻找有效的治疗措施(药物).方法 采用3种培养基对28个人工饲养的发病林麝脓灶进行病原菌的分离培养、细菌革兰氏染色、镜检,然后对分离病原菌进行16S rRNA 基因PCR扩增及测序分析鉴定,再进一步用BIOLOG自动微生物鉴定系统对3种可疑菌进行生理生化鉴定,用昆明小鼠分组进行系列病理实验,最后用纸片扩散法测定病原菌对22种抗生素的敏感性.结果 脓灶中共分离到12种细菌,其中化脓隐秘杆菌Arcanobacterium pyogenes、绿脓杆菌Pseudomonas aeruginosa、蜡状芽孢杆菌Bacillus cereus的检出率分别为100.0%、21.4%、14.3%,其他菌的检出率较低.用BIOLOG自动微生物鉴定系统鉴定结果与16S rRNA鉴定结果完全一致;小鼠致病性实验中进行了脓液培养后注射,分离到单菌鉴定后进一步分别注射,剖检后进行接种划线鉴定并得到与注射前相同的病菌,确定了这几种菌均具有较强的致病性;药敏实验最终确定针对化脓隐秘杆菌的有效药物为环丙沙星,对这3种病菌的有效药物为克林霉素、环丙沙星.结论 初步确定林麝脓肿病主要是由于化脓隐秘杆菌原发感染,进而引起其他病菌的继发感染和混合感染,最终导致病重死亡;环丙沙星等为敏感药物.     

糖尿病患者足部溃疡感染的病原菌分布及药敏性分析

目的:研究糖尿病患者足部溃疡感染的病原菌分布及药敏性。方法:选取2016年2月至2017年2月我院收治的糖尿病足患者102例作为研究对象,采用全自动细菌鉴定仪和Kirby-Baure(K-B)法分别检测所有患者足部溃疡分泌物中病原菌分布和药敏性。结果:96例成功分离出菌株的糖尿病患者足部溃疡分泌物中共分离出107株菌株,其中革兰阴性菌61株(57.01%)、革兰阳性菌43株(40.19%)和真菌3株(2.80%),占总菌株百分比前三位的病原菌分别为金黄色葡萄球菌22株(20.56%)、奇异变形杆菌14株(13.08%)和肺炎克雷伯菌10株(9.35%);前三位革兰阴性菌(奇异变形杆菌、肺炎克雷伯菌和大肠埃希菌)对亚胺培南、美罗培南、头孢哌酮及阿米卡星的敏感性较高(高于90.00%);金黄色葡萄球菌和表皮葡萄球菌对万古霉素、利奈唑胺及利福平敏感性较高(高于95.00%);粪肠球菌对红霉素、氨苄西林、万古霉素及利奈唑胺敏感性较高(高于90.00%)。结论:糖尿病患者足部溃疡感染的病原菌以金黄色葡萄球菌和奇异变形杆菌为主,耐药情况严峻,临床诊疗过程中应根据药敏结果规范使用抗菌药物。     

An ATP Bioluminescence Assay Applicable to Rapid Fluconazole Susceptibility Testing of Dermatophytes

An ATP bioluminescence assay as a rapid reference method for fluconazole (FLCZ) susceptibility testing of dermatophytes, as well as yeasts, was developed and evaluated by comparing it with viability, turbidity and fungal protein content-based conventional methods. FLCZ susceptibility results obtained with strains of Candida albicans and dermatophytes by the bioluminescence method in high-resolution medium were well correlated with those obtained by conventional methods currently used in clinical microbiology laboratories or reported previously, including a broth dilution method by the National Committee for Clinical Laboratory Standards (NCCLS). Thus, ATP bioluminescence assay can be used to monitor fungal growth in liquid culture media. The procedure has considerable potential for the rapid testing of FLCZ susceptibility of dermatophytes and other fungi.     

Antimicrobial Agents Produced by Marine Aspergillus terreus var. africanus Against Some Virulent Fish Pathogens

Screening of fungal isolates collected from different locations of Alexandria coast, Egypt, was carried out to obtain new biologically active metabolites against some virulent fish pathogens (Edwardsiella tarda, Aeromonas hydrophila, Vibrio ordalli and Vibrio angularuim). Among 26 fungal isolates, Aspergillus terreus var. africanus was identified as the most potent isolate. Production of the bioactive material was optimized using response surface methodology including fermentation media, incubation period, temperature, pH, and thermo-stability. Spectral properties of the gas chromatography/mass spectrum of the ethyl acetate crude extract were determined. Partially purified components of the crude extract were chromatographically separated and bioassayed. Out of ten separated compounds, five were with considerable antibacterial agent. The bio-toxicity of crude showed a slight toxicity against the brine shrimp Artemia salina (LC₅₀ = 1,500 μg/l). Antibacterial activity of the crude was compared with some known standard antibiotics and found to be superior over many where its MIC against some pathogen reached 1 μg/ml.     

Stress-induced Antibiotic Susceptibility Testing on a Chip

We have developed a rapid microfluidic method for antibiotic susceptibility testing in a stress-based environment. Fluid is passed at high speeds over bacteria immobilized on the bottom of a microfluidic channel. In the presence of stress and antibiotic, susceptible strains of bacteria die rapidly. However, resistant bacteria survive these stressful conditions. The hypothesis behind this method is new: stress activation of biochemical pathways, which are targets of antibiotics, can accelerate antibiotic susceptibility testing. As compared to standard antibiotic susceptibility testing methods, the rate-limiting step - bacterial growth - is omitted during antibiotic application. The technical implementation of the method is in a combination of standard techniques and innovative approaches. The standard parts of the method include bacterial culture protocols, defining microfluidic channels in polydimethylsiloxane (PDMS), cell viability monitoring with fluorescence, and batch image processing for bacteria counting. Innovative parts of the method are in the use of culture media flow for mechanical stress application, use of enzymes to damage but not kill the bacteria, and use of microarray substrates for bacterial attachment. The developed platform can be used in antibiotic and nonantibiotic related drug development and testing. As compared to the standard bacterial suspension experiments, the effect of the drug can be turned on and off repeatedly over controlled time periods. Repetitive observation of the same bacterial population is possible over the course of the same experiment.     

Comparative Study of Agar Diffusion Test and the NCCLS Macrobroth Method for In Vitro Susceptibility Testing of Candida spp.

We performed a prospective double-blind study to evaluate the correlation between inhibition zones obtained by a disk-diffusion test, using Neo-sensitabs of fluconazole (Rosco Diagnostica), and the MICs generated by the NCCLS macrobroth dilution assay. Eighty clinical isolates, representing 5 of the clinically relevant species of Candida, were tested simultaneously by both methods. A clear inverse correlation was found between the results obtained by both tests (r = −0.69). In addition, there was high degree of agreement between methods in the identification of susceptible isolates. However, the resistance definition by disk-diffusion test had a positive predictive value of only 17%. Our data support the hypothesis that Rosco Fluconazole Neo-sensitabs have potential as a screening test for the identification of Candida isolates susceptible to fluconazole. Resistant isolates should be further investigated by standardized broth procedures. This revised version was published online in June 2006 with corrections to the Cover Date.     

Antimicrobial activity of various cationic molecules on foodborne pathogens

Antibacterial effects of various arginine- and lysine-rich polycationic proteins and polymers were evaluated by broth and solid dilution assay on a range of foodborne pathogens, Gram-positive and Gram-negative bacteria. The Minimum Inhibitory Concentration (MIC) and the Minimum Bactericidal Concentration (MBC) of α-poly-l-lysine (poly-lys), α-poly-l-arginine (poly-arg) and protamines from herring sperm (clupeine sulphate) and salmon sperm (salmine sulphate) were determined on Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Salmonella typhimurium, Shigella sonnei, Escherichia coli O157:H7 and Pseudomonas aeruginosa. All these molecules showed antibacterial activity on all strains with different MIC and MBC values. The molecular mechanisms underlying the effect of α-poly-l-arginine might be related to the entrance of the molecule into the cell. In fact α-poly-l-arginine labelled with 7-Diethylamino coumarin-3-carboxylic acid, succinimidyl ester (DEAC,SE) showed ability to permeate the cell membrane of B. cereus and E. coli O157:H7.