Dipartimento di Biotecnologie, Sezione di Microbiologia, Siena University Hospital, Siena, Italy.
Clin Microbiol Infect. 2012 Nov;18(11):E452-8. doi: 10.1111/j.1469-0691.2012.03980.x. Epub 2012 Aug 22.
EUCAST breakpoint criteria are being adopted by automatic antimicrobial susceptibility testing systems. The accuracy of the Phoenix Automated System in combination with 2012 EUCAST breakpoints against recent clinical isolates was evaluated. A total of 697 isolates (349 Enterobacteriaceae, 113 Pseudomonas spp., 25 Acinetobacter baumannii, 11 Stenotrophomonas maltophilia, 95 Staphylococcus aureus, 6 coagulase negative staphylococci, 77 enterococci and 21 Streptococcus pneumoniae) with defined resistance phenotypes and well-characterized resistance mechanisms recovered in Spain (n = 343) and Italy (n = 354) were tested. Comparator antimicrobial susceptibility testing data were obtained following CLSI guidelines. Experimental agreement (EA), defined as MIC agreement ±1 log(2) dilution, category agreement (CA) and relative discrepancies (minor (mD), major (MD) and very major discrepancies (VMD)) were determined. The overall EA and CA for all organism-antimicrobial agent combinations (n = 6.294) were 97.3% and 95.2%, respectively. mD, MD and VMD were 4.7%, 1.3% and 2.7%, all of them in agreement with the ISO (ISO20776-2:2007) acceptance criteria for assessment of susceptibility testing devices. VMD were mainly observed in amoxicillin-clavulanate and cefuroxime in Enterobacteriaceae and gentamicin in Pseudomonas aeruginosa, whereas MD were mainly observed in amoxicillin-clavulante in Enterobacteriaceae. mD were mainly observed in Enterobacteriaceae but distributed in different antimicrobials. For S. aureus and enterococci relative discrepancies were low. The Phoenix system showed accuracy assessment in accordance with the ISO standards when using EUCAST breakpoints. Inclusion of EUCAST criteria in automatic antimicrobial susceptibility testing systems will facilitate the implementation of EUCAST breakpoints in clinical microbiology laboratories.
EUCAST 折点标准正在被自动抗菌药敏测试系统采用。本研究评估了 Phoenix 全自动系统结合 2012 年 EUCAST 折点对近期临床分离株的准确性。总共检测了 697 株（349 株肠杆菌科，113 株铜绿假单胞菌，25 株鲍曼不动杆菌，11 株嗜麦芽窄食单胞菌，95 株金黄色葡萄球菌，6 株凝固酶阴性葡萄球菌，77 株肠球菌和 21 株肺炎链球菌），这些分离株在西班牙（n = 343）和意大利（n = 354）的耐药表型和明确的耐药机制得到了很好的描述。参照 CLSI 指南获得了对照药敏测试数据。实验一致性（EA）定义为 MIC 一致性 ±1 倍稀释度，类别一致性（CA）和相对差异（次要差异（mD）、主要差异（MD）和非常大的差异（VMD））被确定。所有微生物-抗菌药物组合（n = 6294）的总体 EA 和 CA 分别为 97.3%和 95.2%。mD、MD 和 VMD 分别为 4.7%、1.3%和 2.7%，均符合 ISO（ISO20776-2:2007）评估药敏检测设备的接受标准。VMD 主要见于肠杆菌科的阿莫西林-克拉维酸和头孢呋辛，铜绿假单胞菌的庆大霉素，MD 主要见于肠杆菌科的阿莫西林-克拉维酸。mD 主要见于肠杆菌科，但分布在不同的抗菌药物中。金黄色葡萄球菌和肠球菌的相对差异较低。Phoenix 系统在使用 EUCAST 折点时，符合 ISO 标准的准确性评估。将 EUCAST 标准纳入自动抗菌药敏测试系统将有助于临床微生物学实验室实施 EUCAST 折点。
