Abstract

Background

Enterococci are intrinsically resistant to clinically achievable concentrations of aminoglycosides. However, high-level resistance to aminoglycosides (HLAR) is primarily due to the acquisition of genes encoding aminoglycoside-modifying enzymes (AMEs). Aminoglycosides along with cell wall inhibitors are given clinically for treating enterococcal infections. The current study was conducted to investigate the rate of HLAR and to determine aminoglycoside resistance encoding genes profile in enterococcal isolates from different clinical specimens.

Results

From 120 Enterococcus species, 50 (41.7%) enterococcal isolates were proven to have HLAR, 78% (39/50) have high-level gentamicin resistance (HLGR), and 74% (37/50) were high-level streptomycin-resistant (HLSR). HLGR isolates carried aminoglycoside modifying gene aac (6′)-Ie-aph (2)-Ia in 26/39 (66.7%) of isolates, whereas 32/37 (86.5%) of HLSR carried aph (3)-IIIa gene and were observed in E. faecalis, E. faecium, E. gallinarum, and E. casseliflavus. The aph (2)-Ib, aph (2)-Ic, and aph (2)-Id that encode HLGR could not be detected.

Conclusions

The high detection rate of HLAR among the studied Enterococcus species and the coexistence of HLGR and HLSR strains provide crucial insights to the necessity of routine testing for HLAR in the microbiology lab. The main AME genes among HLGR and HLSR enterococci were aac (6′)-Ie-aph (2″)-Ia and aph (3′)-IIIa, respectively.

Details

Title
Detection of high level aminoglycoside resistance genes among clinical isolates of Enterococcus species
Author
Diab, Manal 1 ; Salem, Dalia 1 ; El-Shenawy, Ahmed 1 ; El-Far, Amira 1 ; Abdelghany, Aya 2 ; Awad, Alaa Reda 3 ; El Defrawy, Inas 1 ; Shemis, Mohamed 2 

 Theodor Bilharz Research Institute (TBRI), Microbiology Department, Giza, Egypt (GRID:grid.420091.e) (ISNI:0000 0001 0165 571X) 
 Theodor Bilharz Research Institute (TBRI), Biochemistry and Molecular Biology Department, Giza, Egypt (GRID:grid.420091.e) (ISNI:0000 0001 0165 571X) 
 Cairo University, Medical Microbiology and Immunology Department, Faculty of Medicine, Cairo, Egypt (GRID:grid.7776.1) (ISNI:0000 0004 0639 9286) 
Publication year
2019
Publication date
Dec 2019
Publisher
Springer Nature B.V.
ISSN
11108630
e-ISSN
20902441
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2670520842
Copyright
© The Author(s) 2019. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.