Extended-spectrum β-lactamase-producing Shigella strains in Israel, 2000–2004

Abstract

Routine susceptibility testing of 5,616 Shigella isolates at the National Shigella Reference Centre in Israel over a 5-year period (2000-2004) revealed resistance to ceftriaxone in one strain of Shigella boydii 2 and in two strains each of Shigella flexneri 2a, S. flexneri 6, and Shigella sonnei. All seven isolates were confirmed as producers of extended-spectrum beta-lactamase (ESBL) by the combination disk method, the Vitek 1 system, and a modification of the double-disk synergy test, which is based on the inhibitory properties of clavulanic acid, tazobactam, and sulbactam. Tazobactam had the strongest effect in all seven strains. Molecular characterization of the ESBLs identified CTX-M-type enzymes, consisting of the CTX-M-9 group (n = 3), CTX-M-3 (n = 2), CTX-M-39 (n = 1), and CTX-M-2 group (n = 1). Three of the strains also carried bla-(OXA) genes and a bla-(TEM) gene. Although the prevalence of ESBLs in this study was low, further research is needed on the spread and transfer of resistance genes, both in hospitals and in the community.

Molecular characterization of multidrug-resistant Shigella species isolated from epidemic and endemic cases of shigellosis in India

“…Irrespective of serotypes, S. flexneri strains harboured tet(B) as well as bla OXA-1 , and in strain NK2788, bla OXA-1 , bla TEM-1 and tet(A) genes were detected (Table 1). Group 9 CTX-M blactamase has been reported in S. boydii (Vasilev et al, 2007). In this study, bla CTX-M-3 was found in a S. boydii type 1 strain (G24371) and, to our knowledge, this is the first report of this enzyme in this serotype.…”

Strategies to overcome extended-spectrum β-lactamases (ESBLs) and AmpC β-lactamases in shigellae

“…associated with plasmid-mediated AmpC enzymes in Argentina [5] and Taiwan [6] or, more often, with extended-spectrum -lactamases (ESBLs), which have been reported in shigellae from East Asia [7][8][9], the Middle East [10][11][12][13] and Argentina [14]. Most ESBLs in shigellae are now CTX-M types and, as shown by a Korean study, these enzymes are associated with cephalosporin failure [7].…”

Comparative in vitro activity of tigecycline and other antimicrobial agents against Shigella species from Kuwait and the United Arab of Emirates

“…However, it must be stated that although rare, cephalosporin-resistant Shigella spp. have been reported from several countries such as Argentina [25], Israel [26], Lebanon [27], China [16] and USA [28].…”

“…For instance, CTX-M-type ESBL has been reported among S. sonnei isolates in Israel [26], China [16], Lebanon [27] and USA [28]. In the Republic of Korea, Kim et al [5] found both the CTX-M-type and TEM-type ESBLs in 20 isolates of S. sonnei.…”