Department of Infectious Diseases, Medical Microbiology and Hygiene, University Hospital Heidelberg, Heidelberg, Germany.
Department of Infectious Diseases, Medical Microbiology and Hygiene, University Hospital Heidelberg, Heidelberg, Germany.
J Microbiol Methods. 2021 Jun;185:106224. doi: 10.1016/j.mimet.2021.106224. Epub 2021 Apr 16.
Fast detection of carbapenemases in Gram-negative bacilli is necessary for accurate antibiotic treatment, prevention of further spreading and surveillance purposes. We analyzed the current occurrence of gene variants and designed two multiplex PCRs with hydrolysis probes. The assay was developed for the BD MAX™ system that combines DNA extraction and PCR in a fully automated procedure providing results within 3 h and was evaluated for detection of carbapenemases from bacterial isolates and directly from rectal swabs. The assay has a theoretic coverage of 97.1% for carbapenemases detected during the last years by the German National Reference Laboratory (NRL). A collection of 151 isolates from the NRL was used and all carbapenemase-positive bacteria (58/58) were identified correctly. The direct-PCR on rectal swabs revealed additional carbapenemase genes in 7 samples that were not identified by the culture-based method used as reference method. The assay allows detection of carbapenemases from clinical isolates and might also help in rapid detection directly from rectal samples.
快速检测革兰氏阴性杆菌中的碳青霉烯酶对于准确的抗生素治疗、防止进一步传播和监测目的是必要的。我们分析了目前基因变异的发生情况，并设计了两个带有水解探针的多重 PCR。该检测方法是为 BD MAX™ 系统开发的，该系统将 DNA 提取和 PCR 完全自动化，在 3 小时内提供结果，并评估了从细菌分离株和直肠拭子中直接检测碳青霉烯酶的效果。该检测方法的理论覆盖范围为德国国家参考实验室（NRL）在过去几年中检测到的碳青霉烯酶的 97.1%。使用了 NRL 的 151 株分离株，所有碳青霉烯酶阳性菌（58/58）均被正确识别。直肠拭子的直接-PCR 显示，在 7 个样本中发现了培养法作为参考方法未识别的额外碳青霉烯酶基因。该检测方法可用于从临床分离株中检测碳青霉烯酶，也可能有助于直接从直肠样本中快速检测。
