MALDI-TOF MS直接靶板微滴生长测定法在CRKP快速检测中的应用  

Clinical application of MALDI-TOF direct droplet culture method in rapid determination of CRKP

作　　者：吴昕哲 茆海丰[1] 杨晋[1] 左春磊[1] 金丹婷[1] WU Xinzhe;MAO Haifeng;YANG Jin;ZUO Chunlei;JIN Danting(Department of Clinical Laboratory,the First Hospital of Lianyungang,Lianyungang 222002,Jiangsu,China)

机构地区：[1]连云港市第一人民医院检验科,江苏连云港222002

出　　处：《检验医学》2024年第6期587-591,共5页Laboratory Medicine

摘　　要：目的探讨基于基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)的直接靶板微滴生长测定(DOT-MGA)法快速筛查碳青霉烯类耐药肺炎克雷伯菌(CRKP)的准确性和临床应用价值。方法收集2020—2021年连云港市第一人民医院肺炎克雷伯菌临床分离株251株,其中美罗培南敏感123株,CRKP128株。采用DOT-MGA法对4和6μL 2种取样量的所有菌株进行美罗培南耐药性检测。采用微量肉汤稀释法测定菌株的美罗培南最小抑菌浓度(MIC)。以微量肉汤稀释法耐药性分析结果为标准,评价DOT-MGA法耐药性检测结果的准确性。结果以微量肉汤稀释法为标准,孵育生长4 h后,DOT-MGA法2种取样量的敏感性和阴性预测值均为100.0%,其中4μL取样量检测CRKP的特异性为92.5%,阳性预测值为92.8%;6μL取样量检测CRKP的特异性为89.8%,阳性预测值为90.1%。123株美罗培南敏感株的美罗培南MIC_(50)为0.125μg·mL^(-1),MIC_(90)为0.25μg·mL^(-1);128株美罗培南耐药株的MIC_(50)和MIC_(90)均为≥128μg·mL^(-1)。DOT-MGA法与微量肉汤稀释法的一致性分析结果显示,4μL加样量Kappa值为0.88,6μL加样量Kappa值为0.83。结论基于MALDITOF MS的DOT-MGA法筛查CRKP具有较高的准确性,且简便、快捷,可用于快速检测CRKP。Objective To investigate the accuracy and clinical application role of direct-on-target microdroplet growth assay(DOT-MGA)based on matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF MS)for rapid determination of carbapenem-resistant Klebsiella pneumoniae(CRKP).Methods A total of 251 clinical Klebsiella pneumoniae isolates were collected from the First Hospital of Lianyungang from 2020 to 2021,which included 123 meropenem-sensitive isolates and 128 CRKP isolates.The carbapenem resistance of all the isolates was determined by DOT-MGA with 2 sample sizes of 4 and 6μL,and the minimum inhibitory concentration(MIC)of meropenem of each isolate was determined by broth microdilution method.Using the results of broth microdilution method as reference,the accuracy of DOT-MGA drug resistance results was evaluated.Results With the broth microdilution method as reference,the sensitivity and negative predictive value of DOT-MGA were 100.0%after incubation and growth for 4 h,and the specificity and positive predictive value of 4μL group were 92.5%and 92.8%,respectively.The specificity and positive predictive value of 6μL group were 89.8%and 90.1%,respectively.The MIC_(50) of 123 meropenem-sensitive isolates was 0.125μg·mL^(-1),and the MIC_(90) was 0.25μg·mL^(-1).The MIC_(50) of 128 meropenem-resistant isolates was≥128μg·mL^(-1),and the MIC_(90) was≥128μg·mL^(-1) as well.The consistency analysis results of DOT-MGA and broth microdilution method showed that the Kappa value of 4μL group was 0.88,and that of 6μL group was 0.83.Conclusions DOT-MGA based on MALDI-TOF is a simple,rapid and accurate method for the determination of CRKP,which can be used in the rapid determination of CRKP in clinical practice.

关 键 词：碳青霉烯类耐药肺炎克雷伯菌 基质辅助激光解吸电离飞行时间质谱 直接靶板微滴生长测定法 微量肉汤稀释法 

分 类 号：R378.99[医药卫生—病原生物学]