副猪嗜血杆菌江西分离株药物敏感性及四环素耐药基因tet(B)分析

摘要

为了解副猪嗜血杆菌江西株的药物敏感性及其耐药基因,本实验采用K-B法测定分离株对57种药物的敏感性,结果显示20株副猪嗜血杆菌均对阿洛西林和万古霉素敏感,80％及以上的分离株对氨苄西林舒巴坦、阿莫西林棒酸等高度敏感.但分离株对恩诺沙星、氨曲南、四环素等的耐受性较强,某些菌株对多种药物具有抗性,其中6株菌能够耐受5种药物,5株菌能够耐受12种药物,3株菌能够耐受13种药物,甚至有2株菌能够耐受多达22种药物.将江西分离株的药物敏感性结果与其它国家或地区以及不同时间分离菌株的结果相比较表明,不同地区及不同时间段分离的菌株药物敏感性存在较大差异.为探索副猪嗜血杆菌耐药的分子机制,本研究设计引物并建立了检测四环素耐药基因tet(B)的PCR方法.运用所建立的方法检测江西株tet(B)基因,在15株四环素耐药菌株中检测出其中9株菌存在该基因,推测tet(B)可能是介导该菌对四环素耐药的主要分子机制之一.%To investigate the antibiotic sensitivity and genes mediated the insistence in Haemophilus parasuis, A total of 20 Jiangxi H. Parasuis isolates were tested with 57 antibiotics by a K-B method. The results showed that all the isolates were susceptible to azlocilin, enrofloxacin and vancomycin, while eighty percent of the isolates was susceptible to Ampicillin/ Sulbatam, Amoxicillin/Clavulanic acid, etc. Howerver, a high level of resistance was found for Enrofloxacin, Aztreonam, Tetracycline etc. Several multiresistance patterns were found among the isolates, of which resistant to 5 or even to 22 antibiotics. Furthermore, A PCR assay was established to detect the tetracycline drug resistance gene tet(B) for the H. Parasuis isolates and nine of the 15 Jiangxi isolates resistanted to tetracycline were positive, which indicated that tet(B) might be one of the main molecular mechanisms mediated the resistance to tetracycline.