Global Health and Tropical Medicine (GHTM), Unit of Medical Microbiology, Instituto de Higiene e Medicina Tropical (IHMT), Universidade NOVA de Lisboa (UNL), Lisbon, Portugal.
Institute of Microbiology and Epizootics, Centre of Infection Medicine, Freie Universität Berlin, Berlin, Germany.
Microb Drug Resist. 2021 Nov;27(11):1555-1559. doi: 10.1089/mdr.2020.0402. Epub 2021 May 5.
Apramycin and florfenicol are two antimicrobial agents exclusively used in veterinary medicine. Resistance determinants to these antimicrobial agents have been described in several staphylococci, yet no inhibition zone-based epidemiological cutoff (ECOFF) values are available to detect populations harboring resistance mechanisms. In this study, we propose disk diffusion inhibition zone ECOFF values of for apramycin and florfenicol. The susceptibility to apramycin and florfenicol was evaluated by disk diffusion of five collections, comprising 352 isolates of animal ( = 265) and human ( = 87) origin. The aggregated distributions of inhibition zone diameters were analyzed by the normalized resistance interpretation method to obtain normalized wild-type (WT) population distributions and corresponding ECOFF values. The putative WT populations of were characterized by an inhibition zone ≥15 mm (ECOFF = 15 mm) for apramycin and ≥21 mm for florfenicol (ECOFF = 21 mm). Five nonwild-type (NWT) isolates were detected for apramycin, all without inhibition zone and harboring the gene, whereas five NWT isolates were identified for florfenicol, all carrying the gene. The proposed ECOFF values for apramycin and florfenicol may be a valuable tool in future antimicrobial resistance monitoring and surveillance studies to identify NWT populations toward these antimicrobial agents.
安普霉素和氟苯尼考是两种仅用于兽医的抗菌药物。已经在几种葡萄球菌中描述了这些抗菌药物的耐药决定因素，但没有基于抑菌圈的流行病学截断值（ECOFF）值可用于检测携带耐药机制的群体。在这项研究中，我们提出了安普霉素和氟苯尼考的抑菌圈 ECOFF 值分别为 和 。通过对五个 集的药敏纸片扩散抑制圈实验，评估了安普霉素和氟苯尼考的敏感性，这五个集共包含 352 株动物（ = 265）和人类（ = 87）来源的分离株。通过归一化耐药解释方法分析抑菌圈直径的聚集分布，获得归一化野生型（WT）群体分布和相应的 ECOFF 值。 的假定 WT 群体特征为安普霉素的抑菌圈≥15 mm（ECOFF = 15 mm），氟苯尼考的抑菌圈≥21 mm（ECOFF = 21 mm）。在安普霉素方面，检测到 5 株非野生型（NWT）分离株，它们均无抑菌圈且携带 基因，而在氟苯尼考方面，检测到 5 株 NWT 分离株，它们均携带 基因。提出的安普霉素和氟苯尼考 ECOFF 值可能是未来抗菌药物耐药性监测和监测研究中识别这些抗菌药物的 NWT 群体的有用工具。
