High incidence of virulence determinants, aminoglycoside and vancomycin resistance in enterococci isolated from hospitalized patients in Northwest Iran

Abstract

Background Multidrug resistant (MDR) enterococci are important nosocomial pathogens causing serious problem in hospitalized patients. The aim of present study was to investigate the frequency of high-level aminoglycoside-resistant and vancomycin-resistant enterococci (VRE) and virulence encoding genes in enterococci isolated from hospitalized patients. Methods A total of 100 enterococci isolated from urine samples of hospitalized patients with symptomatic urinary tract infections were investigated for antimicrobial susceptibility, the frequency of aminoglycoside and vancomycin resistance genes (including aac (6′)-Ie-aph (2“)-Ia, aph (3’)-IIIa, ant (4’)-Ia, aph (2”)-Ic, aph (2“)-Ib, aph (2”)-Id, ant (3″)-III, ant (6′)-Ia, vanA, vanB and vanC ) and virulence encoding genes (including gelE, PAI, esp, ace, cyl, hyl and sprE ). Results Enterococcus faecalis species was identified as predominant enterococci (69%), followed by “other” Enterococcus species (21%) and E. faecium (10%). Ninety three percent of isolates were resistant to one or more antimicrobial agents, with the most frequent resistance found against tetracycline (86%), ciprofloxacin (73%) and quinupristin-dalfopristin (53%). Gentamicin and streptomycin resistance were detected in 50 and 34% of isolates, respectively. The most prevalent aminoglycoside resistance genes were ant (3″)-III (78%) and aph (3′)-IIIa (67%). Vancomycin resistance was detected in 21% of isolates. All E. faecium isolates carried vanA gene, whereas, the vanB gene was not detected in Enterococcus species. The most frequent virulence gene was ace (88.6%), followed by esp (67.1%), PAI (45.5%) and sprE (41.7%). Conclusion Our study revealed the high frequency of gentamycin resistance and VRE in E. faecium isolates, with a high prevalence and heterogeneity of virulence and resistance genes. Due to high frequency of MDR enterococci, it seems that the appropriate surveillance and control measures are essential to prevent the emergence and transmission of these isolates in hospitals.

Drug Resistance Determinants in Clinical Isolates of Enterococcus faecalis in Bangladesh: Identification of Oxazolidinone Resistance Gene optrA in ST59 and ST902 Lineages

“…The prevalence of GEN-HLR in the present study (11.4%) was substantially lower than in recent reports from India, the Middle East, Australia, and Japan (22-55%) [32,[34][35][36][37]. However, aac(6 )-Ie-aph(2")-Ia, which is responsible for GEN-HLR, was more prevalent (21.9%) than the phenotypically detected GEN-HLR.…”

Improved detection of esp, hyl, asa1, gelE, cylA virulence genes among clinical isolates of Enterococci

“…Nevertheless, the presence of virulence determinants in the clinical isolates might contribute to increased severity as they could be expressed under optimum conditions in vivo. Metadata of the previous studies on the detection of virulence genes of enterococci by multiplex/duplex/simplex PCR is depicted in Additional file 1: Table S1 [18,27,29,[33][34][35][36][37][38][39][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59].…”

Molecular characterization and epitope-based vaccine predictions for ompA gene associated with biofilm formation in multidrug-resistant strains of A.baumannii

“…A similar study conducted in Iran suggested that the multidrug-resistant property of the bacteria will prove to be more virulent and thus causes nosocomial infections. The preventive measure to control such infection contains the inception and spread of the extremely drug-resistant (XDR) A. baumannii (Zeighami et al 2019 ) . Multiplex PCR assay of the strains was carried out in clonal lineage analysis.…”