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

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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