Neo-Sensitab纸片法与微量稀释法检测常见酵母菌对酮康唑敏感性的比较

目的 探讨Neo-Sensitab纸片法检测酵母菌对酮康唑的敏感性及与美国国家临床实验室标准化委员会(NCCLS)的微量稀释法的符合率。方法 采用Rosco酵母真菌药敏纸片对42株常见临床分离的酵母菌作了检测，同时根据NCCLS的M-27A方案采用微量稀释法测定了对酮康唑的最小抑菌浓度(MIC)，并对结果作比较分析。结果 Neo-Sensitab抗真菌药敏纸片法与微量稀释法检测的42株致病酶母菌对酮康唑的敏感性符合率为95．24％。结论 Neo-Sensitab抗真菌药敏纸片法具有操作简便、观察时间短、成本低廉等优点，在临床具有良好的实用性，能及时为临床医生在选择治疗方案时提供参考。     

真菌药敏纸片扩散法实验与应用研究

目的评价氟康唑、两性霉素B、伊曲康唑、酮康唑4种抗真菌药物在萄萄糖美蓝M-H琼脂培养基上进行K-B纸片扩散法药敏试验的可行性。方法应用NCCLS认可的氟康唑纸片扩散法和NCCLS M27-A肉汤稀释法检测氟康唑(FLC)、两性霉素B(AMB)、伊曲康唑(ITC)、酮康唑(KTC)对131株假丝酵母菌的敏感性;用纸片扩散法同时检测2种氟康唑(FLC1:25μg/片;FLC2:15μg/片)纸片的敏感性,对其结果进行比较。结果纸片扩散法中:FLC1与肉汤稀释法符合率为97.71%(128/131);FLC2与肉汤稀释法符合率为96.95%(127/131);AMB、ITC、KTC分别与肉汤稀释法符合率为98.47%(129/131)、98.47%(129/131)、97.71%(128/131)。经Kappa检验,K值分别为:0.8952、0.8681、0.8118、0.8509、0.7190;FLC1、FLC2、AMB、ITC 2种方法一致性优,KTC 2种方法一致性良好。结论葡萄糖美蓝M-H琼脂可代替Shadomy琼脂,适用于常规纸片扩散法真菌药敏试验。     

检测常见酵母菌耐药性的纸片法和微量稀释法比较

目的用纸片法和微量稀释法检测痰液标本分离酵母菌的耐药性并比较两者符合率,试找出一种适用于临床实验室的简便方法。方法采用丹麦ROSCO公司抗真菌药敏纸片法检测痰液标本分离的86株常见酵母菌对5种抗真菌药物的敏感性,同时用法国生物梅里埃公司ATB FUNGUS 2念珠菌药敏板条测定4种抗真菌药物的最小抑菌浓度,对结果进行分析。结果两性霉素B、氟胞嘧啶、氟康唑2种方法完全符合率分别为95.3%、95.3%和88.4%,未出现一种方法敏感而另一种方法耐药的严重错误现象;对86株痰液标本分离常见酵母菌的耐药性进行分析,两性霉素B、制霉菌素和氟胞嘧啶的敏感率高,分别为95.4%、98.8%、95.3%,伊曲康唑的耐药率最高(15.1%)。结论纸片法和微量稀释法相比有很好的一致性,且抗真菌药敏纸片种类多,便于随时根据临床所需增加单个药敏结果,易于在各临床实验室开展。酵母菌唑类抗真菌药物的耐药现象日益严重,应加强酵母菌的耐药性监测。     

检测常见酵母菌耐药性的纸片法和微量稀释法比较

目的用纸片法和微量稀释法检测痰液标本分离酵母菌的耐药性并比较两者符合率,试找出一种适用于临床实验室的简便方法。方法采用丹麦ROSCO公司抗真菌药敏纸片法检测痰液标本分离的86株常见酵母菌对5种抗真菌药物的敏感性,同时用法国生物梅里埃公司ATBFUNGUS2念珠菌药敏板条测定4种抗真菌药物的最小抑菌浓度,对结果进行分析。结果两性霉素B、氟胞嘧啶、氟康唑2种方法完全符合率分别为95．3％、95．3％和88．4％,未出现一种方法敏感而另一种方法耐药的严重错误现象;对86株痰液标本分离常见酵母菌的耐药性进行分析,两性霉素B、制霉菌素和氟胞嘧啶的敏感率高,分别为95．4％、98．8％、95．3％,伊曲康唑的耐药率最高（15．1％）。结论纸片法和微量稀释法相比有很好的一致性,且抗真菌药敏纸片种类多,便于随时根据临床所需增加单个药敏结果,易于在各临床实验室开展。酵母菌唑类抗真菌药物的耐药现象日益严重,应加强酵母菌的耐药性监测。     

评价纸片扩散法检测念珠菌对氟康唑的敏感性及临床应用

美国临床实验室标准化委员会(NCCLS)于1997年公布了酵母菌肉汤稀释法抗真菌药物敏感性试验参考方法(NC-CLS M27-A),并于2002年进行了修订(NCCLS M27-A2)[1],但该类方法操作繁琐,难以在常规工作中开展.2003年NC-CLS公布了酵母菌纸片扩散法抗真菌药物敏感性试验方案(NCCLS M44-P)[2].我们应用此方案检测了临床标本中分离的136株念珠菌对氟康唑的敏感性,并与微量肉汤稀释法测定结果进行了比较,以评价其结果和临床应用可靠性,报告如下.     

评价3种方法检测酵母样真菌对氟康唑敏感性

目的评价3种抗真菌药敏试验检测酵母样真菌对氟康唑敏感性的临床应用研究。方法采用3种方法，即NC—CLS推荐的纸片扩散法、ROSCO纸片扩散法和微量肉汤稀释法（ATBFUNGUS2，法国生物梅里埃），检测107株酵母样真菌对氟康唑的敏感性。结果NCCLS推荐的纸片扩散法与丹麦ROSCO纸片扩散法、ATB FUNGUS2符合程度分别为94．4％、91．6％，均无一种方法敏感或耐药而其他2种方法为耐药或敏感的严重误差。结论ROSCO纸片扩散法和ATBFUN—GUS2对氟康唑的检测结果与NCCLS推荐的纸片扩散法相比符合率好，准确率高，监测的抗真菌药物种类多，更适合在临床中推广应用。     

恶性肿瘤患者念珠菌临床分离株的药物敏感性分析

目的 以美国临床实验室标准化委员会（NCCLS） M27-A方案的微量肉汤稀释法为金标准,评价丹麦ROSCO公司的纸片扩散法在检测念珠菌耐药性方面的应用价值,为临床实验室寻找一种简便的念珠菌药敏试验方法.方法 分别采用丹麦ROSCO公司抗真菌药敏纸片和法国生物梅里埃公司ATBFUNGUR2念珠菌药敏板条来检测78株常见念珠菌对5-氟胞嘧啶、两性霉素B、氟康唑、伊曲康唑等4种抗真菌药物的敏感性,以NCCLS的微量稀释法作为金标准,评价纸片扩散法的灵敏度、特异度、阳性预测值、阴性预测值.结果 纸片扩散法检测5-氟胞嘧啶、两性霉素B、氟康唑、伊曲康唑的药敏结果,其Kappa值达到了0.89,未出现一种方法敏感而另一种方法耐药的严重错误现象;对78株念珠菌的药敏结果进行分析,5-氟胞嘧啶、两性霉素B敏感性高,分别为88.20％和89.17％,氟康唑和伊曲康唑敏感性较低,分别为56.34％和52.12％.白色念珠菌和热带念珠菌对4种抗真菌药物的敏感性较高,分别为90.95％、85.71％,而光滑念珠菌和克柔念珠菌的敏感性低,分别为67.50％、41.67％.结论 纸片扩散法与微量稀释法一致性高,在临床实验室可以替代微量稀释法进行念珠菌的药敏分析.我院念珠菌对两性霉素B的敏感性最高,对伊曲康唑的敏感性最低;抗真菌药物对白色念珠菌的抑菌率最高,对克柔念珠菌的抑菌率最低.     

氟康唑体外抗菌活性及五种体外敏感试验方法的比较

目的 对比研究五种酵母菌体外药敏试验方法在测定氟康唑对酵母菌的体外活性检测上的可靠性及实用性。方法 分别应用美国临床实验室标准化委员会（NCCLS）M27-A常量肉汤稀释法、微量肉汤稀释法，NCCLS及ROSCO纸片扩散法、浓度梯度法测定氟康唑对155株临床分离的酵母菌及4株质控菌株的体外活性。采用WHONET-5软件及SPSS软件对结果进行分析，比较各种药敏试验方法与M27-A常量肉汤稀释法的相关性。结果 4种体外药敏试验方法所得结果分别同M27-A常量肉汤稀释法进行比较，浓度梯度法一致率为83．9％，NCCLSM44-P纸片扩散法一致率83．1％，ROSCO纸片扩散法一致率为78．1％，微量肉汤稀释法一致率为93．5％。结论 5种酵母菌体外药敏试验方法在检测氟康唑对临床常见酵母菌的体外活性检测上存在一定的差异，本次试验结果表明，微量肉汤稀释法与NCCLSM27-A常量肉汤稀释法的一致性最佳，其方法结果准确可靠、重复件好．活用于常规下作。     

2种药敏试验方法检测酵母菌对氟康唑敏感性的比较

目的　研究纸片扩散法和真菌耐药性分析试剂盒 (CANDIFAST)检测酵母菌对氟康唑敏感性结果的差异。方法　同时应用美国临床实验室标准化委员会 (NCCLS)认可的酵母菌纸片扩散法和CANDIFAST检测1 1 3株临床分离酵母菌对氟康唑的敏感性 ,并与临床资料进行比较。结果　纸片扩散法和CANDIFAST所测酵母菌对氟康唑的总敏感率分别是 93.8% (1 0 6 /1 1 3)和 5 4 .0 % (6 1 /1 1 3)。 2种方法检测的结果差异有显著性 (P<0 .0 1 ) ,与临床治疗结果相比较 ,纸片扩散法的符合率平均高达 99.5 % ,明显高于CANDIFAST (符合率平均6 3.8% )。结论　NCCLS认可的酵母菌纸片扩散法的测定准确性优于CANDIFAST。     

2种药敏试验方法检测酵母菌对氟康唑敏感性的比较

目的研究纸片扩散法和真菌耐药性分析试剂盒(CANDIFAST)检测酵母菌对氟康唑敏感性结果的差异.方法同时应用美国临床实验室标准化委员会(NCCLS)认可的酵母菌纸片扩散法和CANDIFAST检测113株临床分离酵母菌对氟康唑的敏感性,并与临床资料进行比较.结果纸片扩散法和CANDIFAST所测酵母菌对氟康唑的总敏感率分别是93.8%(106/113)和54.0%(61/113).2种方法检测的结果差异有显著性(P<0.01),与临床治疗结果相比较,纸片扩散法的符合率平均高达99.5%,明显高于CANDIFAST(符合率平均63.8%).结论 NCCLS认可的酵母菌纸片扩散法的测定准确性优于CANDIFAST.     

Comparison of Etest and a tablet diffusion test with the NCCLS broth microdilution method for fluconazole and amphotericin B susceptibility testing of Candida isolates

Three methods were compared for the susceptibility testing of yeast isolates to fluconazole and amphotericin B: two fagar diffusion methods (Etest and a tablet diffusion test) and the National Committee for Clinical Laboratory Standards (NCCLS) broth microdilution method. Given as MIC(50)s (range), fluconazole endpoints were: for the 24 h broth microdilution test, 0.25 mg/L (0.06-32 mg/L); for the Etest, 0.38 mg/L (0.064-24 mg/L); and for the NCCLS broth microdilution test, 2 mg/L (0.06->or=64 mg/L). With breakpoints of <3 mg/L for susceptible and >16 mg/L for resistant, the Etest and the 24 h microdilution test classified the isolates in agreement with the classification obtained by the NCCLS method. Results obtained by Etest were in closer NCCLS method than those obtained with the tablet test. Amphotericin B endpoints were lower for the 24 h microdilution and Etests than MICs obtained by the NCCLS broth microdilution method. Reproducibility was high for all tests; however, disadvantages of both diffusion tests were microcolonies in the inhibition zone and dependence on stringent standardization of inoculum.     

Comparison of various in vitro susceptibility methods for testing Stenotrophomonas maltophilia

A total of 57 clinical isolates were screened by disk diffusion for a related pharmacodynamic study. Testing was performed using National Committee for Clinical Laboratory Standards guidelines, except that results were interpreted at 16 to 18 h and 48 h. Of the 57 isolates, 19 were randomly chosen for additional comparative susceptibility testing of five methods (disk diffusion, Etest, Alamar colorimetric broth microdilution, Vitek, and MicroScan) and an in-house broth microdilution method. The two diffusion methods (disk and Etest) had the closest correlation. The commercial broth microdilution methods and the in-house microdilution method generated inconsistent results for all agents except trimethoprim-sulfamethoxazole. Vitek compared poorly with both diffusion and microbroth dilution methods. The most significant discrepancies were evident with all methods when the incubation period was extended to 48 h. When results were interpreted at 48 h, the incidence of resistance for all bactericidal agents was approximately double the resistance observed at 16 to 18 h. The bacteriostatic agents, trimethoprim-sulfamethoxazole and doxycycline, demonstrated the greatest in vitro activity and were least influenced by extended incubation with diffusion methods. Because correlative in vivo and in vitro studies have not revealed an effective therapeutic regimen for serious S. maltophilia infections, susceptibility results with all testing methods should be interpreted with caution when choosing therapy for patients with life-threatening infections. Susceptibility testing for this heterogeneous group remains controversial and routine testing, with the possible exception of doxycycline (or minocycline) and trimethoprim-sulfamethoxazole, should be avoided. Our data support that if testing is done with bactericidal agents, consideration should be given to interpretation after 48-h incubation.     

Phenotypic detection of mec A-positive staphylococcal blood stream isolates: High accuracy of simple disk diffusion tests

Detection of oxacillin-resistance in staphylococci by phenotypic methods remains problematic. Although standardized susceptibility test methods are adequate for Staphylococcus aureus, many are less satisfactory for the coagulase-negative staphylococci (CNS). We have studied 108 consecutive blood culture isolates of staphylococci. The mec A gene was detected by PCR in one S. aureus and 55 CNS isolates. Susceptibility testing was performed as follows: oxacillin (1-μg), ceftizoxime (30-μg), and cephalothin (30-μg) by disk diffusion; oxacillin, ceftizoxime, cephalothin, methicillin, ampicillin, ampicillin/sulbactam, penicillin, cefazolin, imipenem, and meropenem by the broth microdilution method. In addition, isolates were tested by the oxacillin agar screen plate method. The single oxacillin-resistant S. aureus strain was detected by all oxacillin susceptibility test methods and by the ceftizoxime disk and MIC methods. Two oxacillin-susceptible S. aureus were intermediate (minor error) by ceftizoxime broth microdilution (MIC, 16 μg/mL). The most sensitive, simple phenotypic methods for detection of oxacillin-resistant CNS (mec A positive) were as follows: oxacillin disk diffusion at 98%, oxacillin screen plate at 91%, oxacillin broth microdilution at 87%, ceftizoxime disk diffusion at 100%, ceftizoxime broth microdilution at 87%, and methicillin broth microdilution at 83%. These results indicate that oxacillin and ceftizoxime disk diffusion tests are the most accurate phenotypic methods in routine clinical use for detection of oxacillin-resistant CNS. Oxacillin broth microdilution MIC testing (2% NaCl supplement) would perform more satisfactorily (100% sensitivity) with an adjusted interpretive breakpoint at ⩽0.5 μg/mL, in contrast to the lower accuracy of the “so-called” reference agar screen test.     

Comparative antibiotic sensitivity testing of bacteria with a paper disc and a tablet method

A paper disc method (AB Biodisk, Sweden) and a tablet method (Neo-Sensitabs, A/S Rosco, Denmark) for antibiotic sensitivity testing of bacteria were compared. About three fourths of the bacterial strains could be classified in the same sensitivity groups when tested with the two methods. When discrepancies were noted, they were mostly of minor size.     

Evaluation of disk diffusion method for determining posaconazole susceptibility of filamentous fungi: comparison with CLSI broth microdilution method

The disk diffusion method was evaluated for determining posaconazole susceptibility against 78 strains of molds using two culture media in comparison with the CLSI (Clinical Laboratory Standards Institute) broth microdilution method (M38-A). A significant correlation between disk diffusion and microdilution methods was observed with both culture media.     

In Vitro Activity of Fosfomycin against a Collection of Clinical Pseudomonas aeruginosa Isolates from 16 Spanish Hospitals: Establishing the Validity of Standard Broth Microdilution as Susceptibility Testing Method

The broth microdilution method for fosfomycin and Pseudomonas aeruginosa was assessed and compared with the approved agar dilution method in 206 genetically unrelated P. aeruginosa clinical isolates. Essential agreement between the two methods was 84%, and categorical agreement was 89.3%. Additionally, Etest and disk diffusion assays were performed. Results validate broth microdilution as a reliable susceptibility testing method for fosfomycin against P. aeruginosa. Conversely, unacceptable concordance was established between Etest and disk diffusion results with agar dilution results.     

金黄色葡萄球菌对万古霉素敏感性试验方法评价

目的比较不同方法检测金黄色葡萄球菌对万古霉素敏感性试验结果。方法将1株从临床标本中分离的异质性耐万古霉素的金黄色葡萄球菌(h-VRSA)在含有不同浓度的万古霉素培养基上连续转种诱导,得到一系列对万古霉素不同程度耐药的菌株,分别用琼脂筛选法、微量肉汤稀释法、E-test法、纸片扩散法和仪器法对万古霉素的敏感性进行检测。结果琼脂筛选法、微量肉汤稀释法和E-test法可以检测出金黄色葡萄球菌对万古霉素中介耐药(VISA),而纸片扩散法和仪器法则不能检出VISA。结论微量肉汤稀释法和E-test法是检测金黄色葡萄球菌对万古霉素敏感性可接受的方法。若以纸片扩散法和仪器法为常规药敏试验的实验室,应增加含6μg／ml的万古霉素脑心浸液琼脂进行筛查,以加强对VRSA和VISA的监测。     

Antimicrobial susceptibility testing of Helicobacter pylori comparison of E-test,broth microdilution,and disk diffusion for ampicillin,clarithromycin, and metronidazole

The optimal method for the determination of the minimum inhibitory concentration (MIC) of antimicrobials against Helicobacter pylori has not been established. The epsilometer agar diffusion gradient test (E-Test; AB Biodisk, Solna, Sweden) was compared with broth microdilution, the reference method, and disk diffusion for the antimicrobial susceptibility testing of 122 clinical isolates of H. pylori to ampicillin, clarithromycin, and metronidazole. Isolates were considered to be resistant when the MIC value was >8 μg/ml for either ampicillin or metronidazole and >2 μg/ml for clarithromycin. For an individual isolate, the MICs for ampicillin and clarithromycin determined by broth microdilution and the E-test were highly reproducible, with replicate results being within ±1 log₂ dilution. The correlation between the MICs determined by E-test and broth microdilution was excellent for both ampicillin and clarithromycin (90.1% and 88.5% were within ±log₂ dilution, and 98.3% and 96.7% of the values were within ±2 log₂ dilution, respectively). In no instance did the interpretation of “sensitive” or “resistant” differ. Conversely, only 70.5% of the E-test results for metronidazole were within ±1 log₂ dilution of the broth microdilution results. In addition, 15 (12.3%) of the H. pylori isolates interpreted as resistant by the E-test were sensitive by the broth microdilution method. All discrepancies occurred when the E-test MIC values fell between 8 and 32 μg/ml. The results of the ampicillin and clarithromycin disk diffusion assay correlated 100% with the results of the broth microdilution. However, these data suggest that when the E-test MIC results for metronidazale yield values between 8 and 32 μg/ml, the MIC should be reevaluated by another method.