Rise of antibiotic resistance in clinical enterococcal isolates during 2001–2016 in Iran: a review

Abstract

IntroductionThe clinical significance of enterococci is mostly related to its antibiotic resistance which contributes to colonization and infection, in particular amongst the hospitalized patients. The present review has examined the literature to provide a comprehensive data on enterococci antibiotic resistance during the last 20 years in Iran.MethodsSearch engines such as Google Scholar and PubMed were used to identify all Persian and English-language articles investigating enterococci in Iran from 1996 to 2017. The search terms were “enterococci”, “enterococcal”, “enterococcus”, “Iran”, “bacterial resistance”, “antibiotic resistance” and “resistance”.ResultsDecrease in the resistance trend against ampicillin, gentamycin and ciprofloxacin was observed over a period of 15 years (2001 to 2016) in Iran. During a 10 years period from 2001 to 2015, the rate of resistance among Enterococcus faecalis species was less than Enterococcus faecium. The resistancerate, however, was considerably increased for both species during this period. The mean resistance rates for vancomycin, gentamicin, ciprofloxacin, erythromycin, nitrofurantoin, chloramphenicol, trimethoprim-sulfametoxazol, imipenem and teicoplanin were higher among complicated cases (patients with underlying debilitating disorders) compared to general cases (hospitalized or outpatients with no specific underlying disorder).ConclusionsE. faecalis and E. faecium showed a rise in the mean resistance against all the antibiotics during a 10-year period from 2010 to 2015. With the exception of penicillin and ampicillin, resistance to all antibiotics was higher amongst complicated cases compared to general patients.

Distribution of acquired antibiotic resistance genes among Enterococcus spp. isolated from a hospital in Baotou, China

“…However, the isolates were highly sensitive to the following antibiotics: teicoplanin (0 resistant strains), linezolid (0 resistant strains), and vancomycin (0 resistant strains), similar to other reports [16]. In this study, the rate of ampicillin resistance in E. faecium species showed a significant difference when compared to that of E. faecalis , which is in agreement with previous studies [17].…”

Antibiotic susceptibility pattern of Enterococcus isolates in a five year period at a tertiary care hospital

“…In a literature review, E. faecalis was reported to have a high resistance rate against erythromycin (67% resistance), gentamicin (65%), trimethoprim/sulfamethoxazole (54%), ciprofloxacin (51%) and oxacillin (49%), whereas nitrofurantoin (4% resistance) and teicoplanin (9%) were the most active agents against this species. On the other hand, E. faecium isolates were reported to be mostly resistant against erythromycin (78%), norfloxacin (84%), imipenem (82%) and trimethoprim/sulfamethoxazole (81%), whereas linezolid with no resistance and nitrofurantoin (16%) were the most effective antibiotics [14]. Huang et al [15] also reported greater resistance rates of E. faecium than E. faecalis as in our study.…”

<p>Antibiotic Resistance and Molecular Epidemiology of Vancomycin-Resistant Enterococci in a Tertiary Care Hospital in Turkey</p>

“…4,6 The rate of high-level gentamicin resistance (HLGR) in E. faecium is reportedly low in Cyprus (4.9%) and Luxemburg (12.9%) but relatively high in Turkey (52.3%), Iran (74.9%), and Korea (91.6%). [21][22][23][24] According to Central Asia and Eastern European Surveillance of Antimicrobial Resistance data, 65%-95% of E. faecium isolates are resistant to ampicillin and 81%-97% are classified as HLGR. 25 In India, the rates of ampicillin resistance and HLGR are 80% and 77.1%, respectively.…”

“…6,7 Linezolid resistance in Enterococcus species is related to a mutation in the 23S rRNA gene region as well as the presence of the plasmid-encoded chloramphenicol-florfenicol resistance (cfr) gene. 6,27,28 According to various studies, the rate of linezolid resistance in enterococci is low in Iran (0.7%), Turkey (1%), and Australia (1.3%) 17,23,29 but relatively high in Canada (13.7%). 30 In this study, all VREfm strains were susceptible to daptomycin.…”