Extended-Spectrum β-Lactamases among Enterobacteriaceae Isolated from Urinary Tract Infections in Gaza Strip, Palestine.

This study indicates that bla CTX-M-15 was the most prevalent β-lactamase in this region. Our study demonstrates for the first time in Palestine the identification of bla CTX-M-15 in P. rettgeri and S. liquefaciens, also bla CTX-M-37 in E. cloacae. The coexpression of multiple β-lactamase genes with aac(6')-Ib-cr and qnr in the presence of ISEcp-1 and integrons in individual strains will increase the dissemination of highly resistant strains. ESBL producers were more resistant than non-ESBLs producers for almost all tested antibiotics.