Characterization of Extended-Spectrum Beta-Lactamases in Some Enterobacteriaceae Clinical Isolates from Egyptian Patients

Objectives: to investigate and characterize ESBLs enzymes among Enterobacteriaceae clinical strains isolated from Egyptian patients.Methods and findings: ESBLs and AmpC producers were identified phenotypically.  Beta-lactamases genotypic identification was performed for Escherichia, Klebsiella and Enterobacter spp. TEM, CTX-M-I CTX-M-IV, OXA-III and SHV genes were detected.This study reported Gram negative bacilli as the predominant pathogens as 343 (89.5%) isolates were recovered from 419 clinical samples isolated from public hospitals, Enterobacteriaceae represent 84.2% of the identified isolates. Escherichia spp. were the most frequent isolates, other isolates were identified as Klebsiella, Enterobacter and Proteus species in frequency of 49.48%, 37.02 %, 5.88 % and 3.46% respectively.TEM was found as the most predominant gene producing ESBLs among Escherichia spp. (81.9%) and less frequent among Klebsiella and Enterobacter spp., 40.5% & 41% respectively.CTX-M-gp I genes were detected among 72.2%, of Escherichia and 56.1% of Klebsiella spp., while CTX-M-IV genes were detected among 52.9% of Enterobacter spp. Regarding OXA-III genes, these were detected in 44.4%, 28.1% & 11.7% of examined Escherichia, Klebsiella and Enterobacter species respectively. While SHV genes were the least frequent among Escherichia spp., SHV was the predominant gene among Klebsiella spp. and moderate in Enterobacter spp. by 6.9%, 72% & 29.4% respectively. TEM-type allele is the most common ESBLs.Conclusion: This is the first report demonstrate different types of ESBLs genes among ESBL and AmpC positive Enterobacteriaceae clinical isolates in Egypt. Our finding reported that Enterobacteriaceae isolates are more predominant among hospital clinical isolates. ESBLs and AmpC producing Enterobacteriaceae are becoming increasingly emerged and involved in infection.