Molecular epidemiology of TEM and SHV extended-spectrum β-lactamases in Klebsiella pneumoniae and Escherichia coli clinical isolates from Chengdu,China

Objective To investigate TEM and SHV ESBLs in Klebsiella pneumoniae and Escherichia coli clinical isolates from West China Hospital of Sichuan University and detect resistance of ESBLs-producing isolates. Methods The TEM and SHV ESBLs-encoding gene was amplified by PCR and was sequenced. And the MIC of eight antibiotics against the ESBLs-producing strains were detected by agar dilution. Results All strains were resistant to cefotaxime; eleven strains were resistant to aztreonam; two were resistant to ceftizidime; eleven, five and three were resistant to ciprofloxacin, amikacin and cefoxidine respectively; All strains were susceptible to imipenem. Ten strains of twelve ESBLs-producing strains carried bla SHV-2, two carried bla TEM-19. Conclusions ESBLs producers were mainly resistant to cefotaxime and aztreonam and most of them were multi-drug resistance; Cefotaxime resistance is partially due to production of SHV-2 and TEM-19 in this study.