Calica Chloe N, Domjacic Neda, Dacanay Jennifer, de Carvalho Lopes Ethel C, Mardoquio Mariel S, Chen Yan, Fattouh Ramzi
Bioinformatics and Computational Biology, University of Toronto, Toronto, Ontario, Canada.
Division of Microbiology, Department of Laboratory Medicine, Unity Health Toronto, Toronto, Ontario, Canada.
Microbiol Spectr. 2025 Aug 5;13(8):e0044125. doi: 10.1128/spectrum.00441-25. Epub 2025 Jul 18.
Infection with carbapenemase-producing organisms (CPOs) is associated with significant morbidity and mortality among hospitalized patients. Thus, the identification of CPOs is an important function of clinical microbiology laboratories. This study evaluates the performance of two lateral flow assays (LFAs), the NG-Test CARBA 5 (CARBA 5) and Genobio K.N.I.V.O. Detection K-Set (Genobio), for the detection of carbapenemases using well-characterized clinical and reference isolates of gram-negative bacterial species. Both LFAs are designed to detect KPC, NDM, VIM, IMP, and OXA-48-like carbapenemases from bacterial growth within 15 minutes. In total, 152 isolates were tested: 10 , 12 , and 130 from various . Among these, 132 harbored a carbapenemase, and 20 were carbapenemase-negative. Additionally, LFAs were scored for background color and test indicator line intensity. For , the CARBA 5 had an overall positive agreement of 100%, while Genobio had a positive agreement of 98.5% because of a failure to detect IMP in a isolate and false cross-reactivity for NDM and OXA-48 in a KPC-positive . Both LFAs demonstrated a positive agreement of 100% among carbapenemase-producing and isolates. Neither LFA falsely detected carbapenemases among carbapenemase-negative isolates, nor was any positivity observed among isolates that carried an off-target carbapenemase. In terms of test indicator line intensity, both LFAs showed comparable performance; however, the Genobio LFA displayed a propensity for higher background signal. Overall, both LFAs demonstrated very good performance in detecting select carbapenemases and offered a fast turnaround time, straightforward interpretation, and minimal hands-on time.IMPORTANCEThis study contributes to the field by providing additional information on the performance of two commercial tests, known generally as lateral flow assays (LFA). These assays are used to identify a family of proteins, called carbapenemases, that cause antibiotic resistance and greatly limit the choices of antibiotics that can be used to treat infection. Our study evaluates the performance of two LFAs in a variety of bacteria, including some that are commonly studied (members of the ) as well as others where less test performance information is available ( and ). Our findings show that the LFAs provide a fast turnaround time and require minimal hands-on time in comparison to other tests. In addition, we provide information about practical factors that could negatively affect how the results are interpreted in busy clinical laboratories, such as the ease of "seeing" and interpreting the results.
感染产碳青霉烯酶的微生物（CPO）与住院患者的高发病率和死亡率相关。因此，CPO的鉴定是临床微生物实验室的一项重要功能。本研究评估了两种侧向流动分析法（LFA），即NG-Test CARBA 5（CARBA 5）和Genobio K.N.I.V.O. Detection K-Set（Genobio），使用特征明确的革兰氏阴性菌临床和参考分离株检测碳青霉烯酶的性能。两种LFA均设计用于在15分钟内从细菌生长物中检测KPC、NDM、VIM、IMP和OXA-48样碳青霉烯酶。总共测试了152株分离株：分别来自不同……的10株、12株和130株。其中，132株携带碳青霉烯酶，20株为碳青霉烯酶阴性。此外，对LFA的背景颜色和测试指示线强度进行评分。对于……，CARBA 5的总体阳性一致性为100%，而Genobio的阳性一致性为98.5%，原因是未能在一株……分离株中检测到IMP，以及在一株KPC阳性……分离株中对NDM和OXA-48出现假交叉反应。两种LFA在产碳青霉烯酶的……和……分离株中均显示出100%的阳性一致性。两种LFA均未在碳青霉烯酶阴性分离株中错误检测到碳青霉烯酶，在携带非目标碳青霉烯酶的分离株中也未观察到任何阳性结果。在测试指示线强度方面，两种LFA表现相当；然而，Genobio LFA显示出背景信号较高的倾向。总体而言，两种LFA在检测特定碳青霉烯酶方面均表现出非常好的性能，并提供了快速周转时间、简单的解读和最少的实际操作时间。重要性本研究通过提供关于两种商业检测（通常称为侧向流动分析法（LFA））性能的更多信息，为该领域做出了贡献。这些检测用于鉴定一类称为碳青霉烯酶的蛋白质，这类蛋白质会导致抗生素耐药性，并极大地限制了可用于治疗感染的抗生素选择。我们的研究评估了两种LFA在多种细菌中的性能，包括一些常见研究的细菌（……的成员）以及其他测试性能信息较少的细菌（……和……）。我们的研究结果表明，与其他检测相比，LFA提供了快速周转时间，且所需的实际操作时间最少。此外，我们提供了有关可能对繁忙临床实验室中结果解读产生负面影响的实际因素的信息，例如结果“观察”和解读的难易程度。
