Laboratory of Microbiology and Virology, National Institute of Gastroenterology "Saverio de Bellis," Research Hospital, Bari, Italy.
Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro," Bari, Italy.
Microb Drug Resist. 2020 Aug;26(8):909-917. doi: 10.1089/mdr.2019.0262. Epub 2020 Feb 26.
antibiotic resistance is a constantly evolving process and local surveillance is warranted to guide clinicians in the choice of therapy. Antibiotic susceptibility testing was performed by E-test on 92 strains, and resistance to clarithromycin and levofloxacin was also evaluated using a commercially available genotyping method. In naïve patients the resistance to clarithromycin, levofloxacin, and metronidazole was 37.7%, 26.2%, and 16.4%, respectively, significantly lower than the percentage found in treated patients. Concomitant resistance to ≥2 antibiotics was also observed in naïve patients. The A2143G mutation of the 23S-rRNA gene was the most frequently detected, also in naïve patients. The highest minimum inhibitory concentration (MIC) value (256 mg/L) was associated with A2142 mutations in all the patients carrying them. For levofloxacin resistance a mutation in codon 87 was detected in 63.9% and in codon 91 in 36.1% of the strains, without significant differences in the patients groups. A mutation in codon 87 was associated with the highest MIC value (32 mg/L). In our area, a high prevalence of primary resistance was detected; these rates were higher in patients who had experienced failure of several courses of therapy. A better knowledge of the local epidemiology of resistance, and the genotypes responsible, will improve the eradication rates.
抗生素耐药性是一个不断演变的过程，需要进行当地监测，以指导临床医生选择治疗方法。对 92 株菌株进行了 E 试验进行抗生素药敏试验，还使用市售的基因分型方法评估了克拉霉素和左氧氟沙星的耐药性。在初治患者中，克拉霉素、左氧氟沙星和甲硝唑的耐药率分别为 37.7%、26.2%和 16.4%，明显低于治疗患者的百分比。初治患者也观察到同时对≥2 种抗生素的耐药性。23S-rRNA 基因的 A2143G 突变是最常见的突变，在初治患者中也是如此。所有携带 A2142 突变的患者中，最低抑菌浓度（MIC）值最高（256 mg/L）。对于左氧氟沙星耐药性，在 63.9%的菌株和 36.1%的菌株中检测到密码子 87 的突变，在患者组中没有显著差异。在 87 个密码子处发生突变与最高 MIC 值（32 mg/L）相关。在我们的地区，检测到原发性耐药的高流行率；在经历了多次治疗失败的患者中，这些比率更高。更好地了解耐药性的本地流行病学和相关基因型将提高根除率。
