OXA-48-like carbapenemase gene remains a hidden threat, as different OXA-48 variants have varying presentations of susceptibility to antibiotics that might affect the treatment decisions. Rapid detection and differentiation of OXA-48-like carbapenemase genes are critical for targeted treatment and infection control. In this study, we aimed to develop high-resolution melting (HRM) analysis for the differentiation of OXA-48 variants. HRM analysis is a post-polymerase chain reaction (post-PCR) method for identification of small variations in nucleic acid sequences based on the PCR dissociation curve. A total of 82 bacterial strains, which consisted of Enterobacteriaceae and non-Enterobacteriaceae, were collected from a tertiary teaching hospital. The sensitivity and specificity of the assay were determined, and the developed assay was evaluated using the collected isolates against conventional-sequencing method. Overall, the developed assay was able to detect isolates that harboured OXA-48 and OXA232/OXA-181 by showing two distinct peaks at 81.1 ± 0.2 °C and 82.1 ± 0.2 °C, respectively. The detection limit of the assay was 1.6 x 10-6 ng/µl for OXA-48 and 1.8 x 10-7 ng/µl for OXA-232/OXA-181. This assay showed 100% specificity when evaluated on a panel of 37 isolates comprised of different species of bacteria and yeasts. When the assay with isolates collected in the year 2016 was first evaluated, the assay showed comparable results with conventional PCR-sequencing method where 34 OXA-48 and OXA-232/OXA-181 were detected. By using HRM analysis, the presence of OXA-48-like variants could be easily identified within 3 hours from the pure culture.

中文翻译：

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使用高分辨率熔解（HRM）分析进行OXA-48-Like变体的一步式差分检测。

像OXA-48一样的碳青霉烯酶基因仍然是一个隐藏的威胁，因为不同的OXA-48变体对抗生素的敏感性表现各异，可能会影响治疗决策。OXA-48样碳青霉烯酶基因的快速检测和分化对于靶向治疗和感染控制至关重要。在这项研究中，我们旨在开发用于OXA-48变异的高分辨率熔解（HRM）分析。HRM分析是一种后聚合酶链反应（PCR）方法，用于根据PCR解离曲线识别核酸序列中的细微变化。一家大专院校共收集了82株细菌，包括肠杆菌科和非肠杆菌科。确定了测定的灵敏度和特异性，并使用收集的分离物按照常规测序方法对开发的测定进行评估。总体而言，通过分别在81.1±0.2°C和82.1±0.2°C处显示两个不同的峰，开发的测定法能够检测出带有OXA-48和OXA232 / OXA-181的分离株。该分析的检出限对于OXA-48为1.6 x 10-6 ng / µl，对于OXA-232 / OXA-181为1.8 x 10-7 ng / µl。当在一组由不同种类的细菌和酵母菌组成的37种分离菌株中进行评估时，该检测方法显示出100％的特异性。首次评估2016年分离株的分析结果时，该分析结果与常规PCR测序方法可比，结果检测到34种OXA-48和OXA-232 / OXA-181。通过使用HRM分析，可以在纯培养后3小时内轻松识别OXA-48-like变体的存在。