Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Vet Microbiol. 2011 Dec 15;153(3-4):339-42. doi: 10.1016/j.vetmic.2011.06.009. Epub 2011 Jun 15.
Helicobacter suis is a very fastidious porcine gastric pathogen, which is also considered to be of zoonotic importance. In vitro antimicrobial susceptibility cannot be determined using standard assays, as this agent only grows in a biphasic medium with an acidic pH. Therefore, a combined agar and broth dilution method was used to analyse the activity of nine antimicrobial agents against nine H. suis isolates. After 48 h microaerobic incubation, minimal inhibitory concentrations (MICs) were determined by software-assisted calculation of bacterial growth. Only for enrofloxacin a bimodal distribution of MICs was demonstrated, indicating acquired resistance in one strain, which showed an AGT→AGG (Ser→Arg) substitution at codon 99 of gyrA. In conclusion, the assay developed here is suitable for determination of the antimicrobial susceptibility of H. suis isolates, although activity of acid sensitive antimicrobial agents may be higher than predicted from MIC endpoints.
猪霍乱螺旋菌是一种非常挑剔的猪胃病原体，也被认为具有动物源性重要性。由于该病原体只能在酸性 pH 值的两相培养基中生长，因此无法使用标准检测方法来确定体外抗菌药物敏感性。因此，采用琼脂和肉汤稀释联合方法来分析 9 种抗菌药物对 9 株猪霍乱螺旋菌分离株的活性。经过 48 小时微需氧孵育，通过软件辅助计算细菌生长来确定最小抑菌浓度（MIC）。只有恩诺沙星显示出 MIC 的双峰分布，表明一株菌发生了获得性耐药，其 gyrA 基因 99 密码子处发生了 AGT→AGG（丝氨酸→精氨酸）取代。总之，这里开发的方法适用于测定猪霍乱螺旋菌分离株的抗菌药物敏感性，尽管酸性敏感抗菌药物的活性可能高于 MIC 终点预测值。
