Centre for Bioinnovation, University of the Sunshine Coast, Sippy Downs, Queensland, Australia.
Sunshine Coast Health Institute, Birtinya, Queensland, Australia.
J Med Microbiol. 2022 Oct;71(10). doi: 10.1099/jmm.0.001593.
Antimicrobial resistance (AMR) is an ever-increasing global health concern. One crucial facet in tackling the AMR epidemic is earlier and more accurate AMR diagnosis, particularly in the dangerous and highly multi-drug-resistant ESKAPE pathogen, . We aimed to develop two SYBR Green-based mismatch amplification mutation assays (SYBR-MAMAs) targeting GyrA T83I (248) and GyrA D87N, D87Y and D87H (259). Together, these variants cause the majority of fluoroquinolone (FQ) AMR in . Following assay validation, the 248 and 259 SYBR-MAMAs were tested on 84 Australian clinical isolates, 46 of which demonstrated intermediate/full ciprofloxacin resistance according to antimicrobial susceptibility testing. Our two SYBR-MAMAs correctly predicted an AMR phenotype in the majority (83%) of isolates with intermediate/full FQ resistance. All FQ-sensitive strains were predicted to have a sensitive phenotype. Whole-genome sequencing confirmed 100 % concordance with SYBR-MAMA genotypes. Our GyrA SYBR-MAMAs provide a rapid and cost-effective method for same-day identification of FQ AMR in . An additional SYBR-MAMA targeting the GyrB S466Y/S466F variants would increase FQ AMR prediction to 91 %. Clinical implementation of our assays will permit more timely treatment alterations in cases where decreased FQ susceptibility is identified, leading to improved patient outcomes and antimicrobial stewardship.
抗微生物药物耐药性（AMR）是一个日益严重的全球健康问题。解决 AMR 流行问题的一个关键方面是更早、更准确地进行 AMR 诊断，尤其是在危险且高度多药耐药的 ESKAPE 病原体中。我们旨在开发两种针对 GyrA T83I（248）和 GyrA D87N、D87Y 和 D87H（259）的基于 SYBR Green 的错配扩增突变分析（SYBR-MAMA）。这些变体共同导致了大多数氟喹诺酮（FQ）在中的 AMR。在对 84 个澳大利亚临床分离株进行了检测，其中 46 个根据抗菌药物敏感性测试显示对环丙沙星具有中间/完全耐药性。我们的 248 和 259 SYBR-MAMA 正确预测了具有中间/完全 FQ 耐药性的大多数（83%）分离株的 AMR 表型。所有 FQ 敏感株均预测为敏感表型。全基因组测序证实与 SYBR-MAMA 基因型的一致性为 100%。我们的 GyrA SYBR-MAMA 提供了一种快速且具有成本效益的方法，可用于当天鉴定中的 FQ AMR。针对 GyrB S466Y/S466F 变体的另一个 SYBR-MAMA 将提高 FQ AMR 预测率至 91%。如果发现 FQ 敏感性降低，我们的检测方法的临床应用将允许更及时地改变治疗方案，从而改善患者的预后和抗菌药物管理。
