Frequency and Antibiotics Resistance of Extended-Spectrum Beta-Lactamase (ESBLs) Producing Escherichia coli and Klebsiella pneumoniae Isolated from Patients in Gaza Strip, Palestine

Extended-Spectrum β-Lactamases (ESBLs) hydrolyze broad-spectrum cephalosporin, monobactam, and penicillin. This study investigated ESBL-producing Escherichia coli and Klebsiella pneumoniae bacteria in the Gaza strip and explored their susceptibility to various antimicrobials to provide a reference for physicians in managing the hospital infection.

Ninety-six isolates, comprising 69 E. coli and 27 K. pneumoniae were obtained from urine, wound, blood, and ear discharge samples from April-June 2013 in Gaza hospitals. The ESBL-producing isolates were screened using the double-disc diffusion test. Antibiotics susceptibility test was determined by the disc diffusion method on Mueller-Hinton agar, and PCR identified β-lactamases genes.

Our results revealed high rates of ESBL-producing K. pneumoniae (59.3%) and E. coli (39.1%) among isolates. About 65.1% of ESBL-producing isolates were susceptible to imipenem while exhibited 100% resistance to cefotaxime and ampicillin and 74.4% to sulfamethoxazole/trimethoprim. Except for imipenem, higher antibiotic resistance rates were observed among ESBL producers than non-ESBL producers. This study showed that the antimicrobial resistance and ESBLs were higher in K. pneumoniae isolates than E. coli isolates, and most K. pneumoniae isolates harbored simultaneously two or three β-lactamases-encoding genes.

High ESBL-producing rates among K. pneumoniae and E. coli isolates and higher resistance rates to antibiotics among ESBL compared to non-ESBL producing isolates necessitate antimicrobial resistance surveillance and molecular characterization of ESBLs-producing bacteria to achieve a specific treatment.