High level aminoglycoside resistant enterococci in hospital-acquired urinary tract infections in Mansoura, Egypt

Introduction Resistance to different antimicrobial agents is increasing in enterococci and effective treatment represents a major health concern. The aim of this study was to determine the antimicrobial resistance patterns and the frequency of high level aminoglycoside resistance (HLAR) among enterococci. Methods A total of 80 enterococcal isolates, (73 Enterococcus faecalis, 7 Enterococcus faecium) were collected from patients with hospital acquired urinary tract infections (UTI) at Mansoura University hospitals in Egypt. Antimicrobial susceptibility testing was performed via the disc diffusion method. PCR was used for identification of species and detection of aminoglycoside-modifying enzymes genes (AME). Results All enterococcal isolates were sensitive to vancomycin and linezolid. Fifty-three isolates exhibited HLAR. Our results show that HLAR was mediated by the presence of multiple AMEs genes. The aac(6')-Ie-aph(2')-Ia gene was associated with aph(3')-IIIa and ant(6)-Ia gene in 69% of HLAR isolates. Conclusion This study showed that enterococci isolated from hospital acquired UTI were resistant to multiple antibiotics. Furthermore, the frequency of high level gentamicin resistance (HLGR) was higher than high level of streptomycin resistance (HLSR). The most common AME genes were aph(3')-IIIa and ant(6)-Ia followed by aac(6')-Ia follwed by aac(6')-Ie-aph(2')-Ia.