Prevalence of CTX-M Beta-Lactamase Producing Escherichia coli in Eastern Province of Saudi Arabia

Abstract

Escherichia coli known for its ability to resist the beta lactam antibiotic group by the production of beta lactamases enzymes, which will hydrolyze broad spectrum of beta-lactam antibiotics and known as ESBL E. coli. Globally, there is more attention on the spread of ESBLs E. coli because the presence of this enzyme will lead to more difficulties in antibiotic selection. The three main ESBL genes are bla SHV, bla TEM and bla CTX-M. The CTX-M ESBL family recently became the most predominant type of ESBL worldwide, and is referred to as the "CTX-M pandemic". Clinical samples were obtained from patients at King Fahad Hospital in Alkhobar city in Eastern Province of Saudi Arabia. Identification and sensitivity was carried out by a VITEK2 analyzer. All ESBL E. coli producers were reconfirmed on an ESBL chromogenic agar. All strains have been through genomic DNA extraction, polymerase chain reaction with specific primers (U-CTX-M, CTX-M-1, CTX-M-9, CTX-M-14, and CTX-M-15), and then went through gel electrophoresis. Plasmid DNA extraction was conducted with a QIAprep Spin Miniprep Kit. A total of 220 clinical samples were obtained, and 30.9% (68/220) of the isolates were ESBL producers. Most of the samples were urine (184/220). ESBL-E. coli showed a high rate of resistance, including trimethoprim/sulfamethoxazole 77.9%, ciprofloxacin 67.7% and gentamicin 26.5 %. Imipenem and Meropenem were both recognized as resistant in 1.5% (n=1) of the isolates. CTX-M was found in 88.2% (n=60) of ESBL E. coli. The distribution was as follows: CTX-M-1 95 %, CTX-M-9 10%, CTX-M-14 21.7% and CTX-M-15 55%. Plasmid was obtained from 53.3 % of all the CTX-M positive isolates. In conclusion, ESBL was found to be high among isolates, most of them harboring the CTX-M gene with the most prevalent CTX-M-1 type. Antibiotic resistance was high among ESBL isolates, and carbapenems was the best treatment choice, hence the recent emergence of carbapenemase is a great concern