Multi-drug resistance strains in Bengal region and analysis of their resistance genes as compared with those in Japan

抗菌药物的过度使用导致了多重耐药菌株的出现，这使得以往容易治愈的细菌感染的治疗变得困难。目的分析重症腹泻患者和环境中分离的耐药菌株的耐药率。孟加拉地区的结果也与日本的结果进行了比较。此外，对分离株中存在哪些类型的耐药基因，尤其是整合子耐药基因进行了分析。2006年在印度加尔各答分离的霍乱弧菌多为O1群，以稻叶血清型为主。药敏分析显示，大多数菌株为多重耐药。超过90%的人对氨苄西林、链霉素、新霉素、萘啶酸和红霉素耐药。另一方面，93%对四环素敏感，50%对环丙沙星耐药。最近发现了一些NAG弧菌…更多的人被错误地识别，现在被证明是河流弧菌。对19株多重耐药河流弧菌的分析表明，9株河流弧菌中检测到1类整合子，4株河流弧菌中检测到SXT元件。药物外排泵参与了所有氟喹诺酮类耐药菌株的耐药。用聚合酶链式反应检测环境中整合酶基因的分布。结果表明，环境中广泛存在intl1和intl2基因。此外，在某些情况下还检测到SXT元件。特别是在孟加拉国，当将耐药基因编码在SXT元件上的链霉素、磺胺甲恶唑和甲氧苄啶加入到培养基中时，O1霍乱弧菌的分离率会增加。然而，在日本，与印度和孟加拉国相比，从腹泻患者中分离的致泻性大肠埃希菌和弯曲杆菌的耐药率相对较低。例如，不到10%的致泻性大肠杆菌和弯曲杆菌对环丙沙星具有抗药性。腹泻患者粪便标本培养中很少检测到Intl1和Intl2基因，也未检测到Intl3基因。然而，在河水和肉类等环境样品的富集物培养中检测到intl1和intl2基因，而在环境样品的富集物培养中未检测到SXT元件，这表明整合子不仅在孟加拉地区广泛分布，在日本也广泛分布于环境水和肉类中。但整合子在孟加拉地区粪便标本中的分布明显高于日本。此外，孟加拉地区患者分离的多重耐药菌株和氟喹诺酮类耐药菌株的比例高于日本。这可能是因为孟加拉地区的药房很容易买到抗菌药物，而不需要处方。较少

Overuse of antimicrobial agents has resulted in the emergence of multiple-drug resistance strains, which make it difficult to treat bacterial infections easily cured previously. The aim of study was conducted to analyze the rate of antimicrobial resistance strains isolated from severe diarrheal cases and the environment. The results obtained from Bengal region were also compared with those from Japan. In addition, what types of antimicrobial resistance genes present, particularly for integron, were analyzed in the isolates. Vibrio cholerae strains isolated in Kolkata, India in 2006 were mostly O1 serogroup in which Inaba serotype was dominant. Analysis of antimicrobial susceptibility revealed that most of the strains were multiple-drug resistance. More than 90% were resistant to ampicillin, streptomycin, neomycin, nalidixic acid, and erythromycin. On the other hand, 93% were susceptible to tetracycline and 50% were resistant to ciprofloxacin. Recently some of the NAG vibrio were found … More to be misidentified and now turned out to be V.fluvialis. Analysis of 19 multiple-drug resistant strains of V.fluvialis exhibited that class 1 integron and SXT element were detected in 9 and 4 strains of V.fluvialis, respectively. Drug efflux pump was involved in the fluoroquinolone resistance of all the fluoroquinolone resistant strains. Furthermore distribution of integrase (intl) gene in the environment was examined by PCR. The results indicated that intl1 and intl2 genes were widely distributed in the environment. In addition, SXT element was also detected in some cases. Particularly, in Bangladesh, isolation rate of V.cholerae O1 increased when streptomycin, sulfamethoxazole and trimethoprim, whose resistant genes are encoded on SXT element, were included in the culture medium. In the case of Japan, however, resistant rates of diarrheagenic Escherichia coli and Campklobacters isolated from diarrheal patients were relatively low in comparison to those in India and Bangladesh. For example, less than 10% of diarrheagenic E.coli and Campylobacters were resistant to ciprofloxacin. Intl1 and intl2 genes were rarely detected in enrichment culture of stool specimen of diarrheal patients and Intl3 gene was not detected at all. However, intl1 and intl2 genes were detected in enrichment culture of the environmental samples such as river water and meat but SXT element was not detected in enrichment culture of the environmental samples.These data indicated that integron is widely distributed not only in Bengal region but also in Japan such in the environmental water and meat. However, distribution of integron in the stool specimen in Bengal region was much higher than that in Japan. Furthermore, the rate of multiple-drug resistance as well as fluoroquinolone resistance strains isolated from patients was higher in Bengal region than in Japan. This could be explained by the easy purchase of the antimicobial agents at the pharmacy without prescription in Bengal region. Less