Presence of Integron-Associated Resistance in the Community Is Widespread and Contributes to Multidrug Resistance in the Hospital

Abstract

Integrons are strongly associated with the multidrug resistance seen in gram-negative bacilli in the hospital environment. No data, however, are available on their prevalence in the community. This study is the first to show that integrons are widespread in Enterobacteriaceae in the community and that integron-associated resistance genes in the community constitute a substantial reservoir for multidrug resistance in the hospital.Multidrug resistance among Enterobacteriaceae in the hospital setting is an increasing problem. The development of control strategies, therefore, is of major importance. The acquisition of an array of resistance genes by horizontal transfer, mediated by plasmids and transposons, is currently thought to play an increasing role in the development of this multiresistance. A substantial portion of the resistance genes present on plasmids and transposons is integrated into DNA elements called class 1 integrons (4, 9). These genetic elements comprise a site-specific recombination system capable of integrating and expressing those genes contained in cassette-like structures.

SGI1-K, a Variant of the SGI1 Genomic Island Carrying a Mercury Resistance Region, in Salmonella enterica Serovar Kentucky

“…The 5Ј-CS of In104-K contains the strong version of the P c promoter [TTGACA (17)TAAACT], which drives transcription of the cassette genes (10), whereas both 5Ј-CS regions in the original SGI1 (GenBank accession no. AF261825) have P c weak [TGGACA (17)TAAGCT], and a G residue replaces the more usual C at the 16th position of the 17-bp P c spacer. The left-hand 5Ј-CS region in SGI1-H (AY458224), which has the same cassette array as SGI1-K, also has the strong version of P c .…”

Colistin-Resistant Klebsiella pneumoniae: Prevalence of Integrons and Synergistic Out Turn for Colistin-Meropenem

“…There are 4 different types of integrons class 1, class 2, class 3, and class 4 of which, class 1 and class 2 integrons are more prevalent in Gram-negative clinical isolates (10). In the hospital sphere, class 1 integrons are robustly aided with multi-drug resistance sighted in Enterobacteriaceae and no data available on the prevalence in the community (11). The report on the newborn plasmid-mediated colistin-resistance gene, mcr-1 in isolates of Escherichiacoli and K. pneumoniae arises from animals, raw meat, and humans; later, it has been reported in various countries.…”

Detection of integrons among multi-drug resistant (MDR) Escherichia coli strains isolated from clinical specimens in northern west of Iran

“…Nearly all known gene cassettes from class 1, 2 and 3 integrons encode resistance to antibiotics or disinfectants (2,11). Class 1 integrons are the most prevalent and well characterized (8,11,12). Class 4 is a distinctive class of integrons located in the Vibrio cholerae genome and is not known to be associated with antibiotic resistance (19).…”