High-level resistance to aminoglycosides and ampicillin among clinical isolates of Enterococcus species in an Iranian referral hospital
-
Seyed Hossein Mousavi
,
Hadi Peeri-Doghaheh
,
Behnam Mohammadi-Ghalehbin
,
Roghayeh Teimourpour
,
Dadras Maleki
,
Farzad Khademi
,
Mohsen Arzanlou
Abstract
Background and Objectives: Nowadays, high-level aminoglycosides and ampicillin resistant Enterococcus species are among the most common causes of nosocomial infections. The present study was conducted to determine the prevalence of high-level resistance to aminoglycosides and ampicillin among clinical isolates of Enterococcus species in Ardabil, Iran.
Materials and Methods: In this cross–sectional study, a total of 111 Enterococcus species were collected from different clinical specimens between 2013 and 2015. Enterococcus species were identified using standard phenotypic and genotypic methods. BHI agar screen and agar dilution methods were used for detection of high-level gentamicin and streptomycin resistance (HLGR and HLSR) and minimal inhibitory concentration (MIC) of ampicillin, respectively.
Results: Of 111 clinical isolates, 59 (53.2%) and 25 (22.5%) isolates were E. faecalis and E. faecium, respectively, based on the PCR results. Totally, 60.3% and 56.7% of isolates were HLGR and HLSR, respectively, as well as 51.35% were HLGR plus HLSR. Among HLGR isolates, 36 (61.01%), 18 (72%) and 13 (48.14%) were E. faecium, E. faecalis and non-faecalis non-faecium species, respectively. Among HLSR isolates, 33 (55.93%), 16 (64%) and 14 (51.85%) were E. faecalis, E. faecium and non-faecalis non-faecium species, respectively. All HLGR isolates contained aac(6´)Ie-aph(2″)Ia gene. Overall, the prevalence of high-level ampicillin resistance among Enterococcus species was 17.1%. For E. faecalis, E. faecium and non-faecalis non-faecium species, ampicillin resistance rates were as follows: 11 (40.74%), 7 (28%) and 1 (1.69%), respectively. For aminoglycoside antibiotics, the resistance rate was significantly higher in E. faecium isolates and for ampicillin it was higher in E. faecalis isolates.
Conclusion: The frequency of high-level aminoglycoside resistant enterococcal isolates in our hospital was high and significant ampicillin resistance was noticed. This would require routine testing of enterococcal isolates for HLAR and ampicillin susceptibility.
2. Susan L Fraser. Enterococcal infections treatment and management. 2018. Available from
https://emedicine.medscape.com/article/216993-treatment
3. Hollenbeck BL, Rice LB. Intrinsic and acquired resistance mechanisms in Enterococcus. Virulence 2012; 3:421-433.
4. Gagetti P, Bonofiglio L, García Gabarrot G, Kaufman S, Mollerach M, Vigliarolo L, et. al. Resistance to β-lactams in enterococci. Rev Argent Microbiol 2019; 51: 179-183.
5. Dutka-Malen S, Evers S, Courvalin P. Detection of glycopeptide resistance genotypes and identification to the species level of clinically relevant enterococci by PCR. J Clin Microbiol 1995;33:24-27.
6. Clinical and Laboratory Standards Institute. Performance standards for antimicrobial susceptibility testing. 26th ed. CLSI supplement M100s. CLSI; 2016.
7. Hidron AI, Edwards JR, Patel J, Horan TC, Sievert DM, Pollock DA, et al. NHSN annual update: antimicrobial-resistant pathogens associated with healthcare-associated infections: annual summary of data reported to the national healthcare safety network at the centers for disease control and prevention, 2006-2007. Infect Control Hosp Epidemiol 2008; 29: 996-1011.
8. Lester CH, Sandvang D, Olsen SS, Schønheyder HC, Jarløv JO, Bangsborg J, et al. Emergence of ampicillin-resistant Enterococcus faecium in Danish hospitals. J Antimicrob Chemother 2008; 62:1203-1206.
9. Asadollahi P, Razavi S, Asadollahi K, Pourshafie MR, Talebi M. Rise of antibiotic resistance in clinical enterococcal isolates during 2001–2016 in Iran: a review. New Microbes New Infect 2018; 26: 92-99.
10. Coombs GW, Pearson JC, Daley DA, Le TT, Robinson JO, Gottlieb T, et al. Australian enterococcal sepsis outcome programme annual report, 2013. Commun Dis Intell Q Rep 2014;38:E320-326.
11. Osuka H, Nakajima J, Oishi T, Funayama Y, Ebihara T, Ishikawa H, et al. High-level aminoglycoside resistance in Enterococcus faecalis and Enterococcus faecium causing invasive infection: Twelve-year surveillance in the Minami Ibaraki Area. J Infect Chemother 2016; 22:61-63.
12. Khodabandeh M, Mohammadi M, Abdolsalehi MR, Hasannejad-Bibalan M, Gholami M, Alvandimanesh A, et al. High-level aminoglycoside resistance in Enterococcus faecalis and Enterococcus faecium; as a serious threat in hospitals. Infect Disord Drug Targets 2020;20:223-228.
13. Khani M, Fatollahzade M, Pajavand H, Bakhtiari S, Abiri R. Increasing prevalence of aminoglycoside-resistant Enterococcus faecalis isolates due to the aac(6’)-aph(2”) gene: A therapeutic problem in Kermanshah, Iran. Jundishapur J Microbiol 2016; 9(3): e28923.
14. Dadfarma N, Fooladi AAI, Oskoui M, Mahmoodzadeh Hosseini H. High level of gentamicin resistance (HLGR) among enterococcus strains isolated from clinical specimens. J Infect Public Health 2013;6:202-208.
15. Behnood A, Farajnia S, Moaddab SR, Ahdi-Khosroshahi S, Katayounzadeh A. Prevalence of aac(6′)-Ie-aph(2″)-Ia resistance gene and its linkage to Tn5281 in Enterococcus faecalis and Enterococcus faecium isolates from Tabriz hospitals. Iran J Microbiol 2013;5:203-208.
16. Emaneini M, Aligholi M, Aminshahi M. Characterization of glycopeptides, aminoglycosides and macrolide resistance among Enterococcus faecalis and Enterococcus faecium isolates from hospitals in Tehran. Pol J Microbiol 2008; 57:173-178.
| Files | ||
| Issue | Vol 12 No 4 (2020) | |
| Section | Original Article(s) | |
| DOI | https://doi.org/10.18502/ijm.v12i4.3935 | |
| Keywords | ||
| Enterococcus faecalis; Enterococcus faecium; High-level resistance; Gentamicin; Streptomycin; Ampicillin | ||
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