Multi-drug-resistant Enterococcus faecalis among Egyptian patients with urinary tract infection

Evolving Enterococcus faecalis Biofilms and Urinary Tract Infection Relapse: Does Vaginal Estrogen Matter?

IMPORTANCE

Enterococcus faecalis urinary tract infection (UTI) is common in postmenopausal females and these bacteria create biofilms that may reduce treatment efficacy. The role of local vaginal estrogen therapy in susceptibility to E. faecalis infection is unclear.

OBJECTIVE

The aim of the study was to evaluate differences in the treatment of relapsing E. faecalis UTIs in postmenopausal women using vaginal estrogen compared to premenopausal women.

STUDY DESIGN

This was a secondary analysis of a retrospective cohort study of 71 female ambulatory patients seen within the gynecology or urogynecology practices between 2011 and 2020. Patients included had symptomatic E. faecalis UTI and a diagnosis of recurrent UTI. Patients with asymptomatic bacteriuria and concurrent pregnancy were excluded. Data was retrieved by chart review, stored, and analyzed utilizing descriptive statistics. A 2-sided Fisher exact test was performed to compare outcomes between postmenopausal and premenopausal patients and the prescription of additional rounds of antibiotics for relapse.

RESULTS

Within this cohort, 57.8% were postmenopausal and 42.2% were premenopausal. There was no statistically significant difference in the need for additional antibiotics between postmenopausal and premenopausal patients (10.8% vs 14.3%, P = 0.72), postmenopausal patients not using vaginal estrogen and premenopausal patients (0% vs 14.3%, P = 0.28), postmenopausal patients using vaginal estrogen and premenopausal patients (20% vs 14.3%, P = 0.70), and among postmenopausal vaginal estrogen users and nonusers (20% vs 0%, P = 0.11).

CONCLUSIONS

A small percentage of premenopausal and postmenopausal patients with recurrent UTI required additional antibiotics for E. faecalis relapse. However, there are no statistically significant differences between our estrogen-deficient or estrogenized postmenopausal patients, and premenopausal patients.

Repurposing fusidic acid as an antimicrobial against enterococci with a low probability of resistance development

Drug repurposing constitutes a strategy to combat antimicrobial resistance, by using agents with known safety, pharmacokinetics, and pharmacodynamics. Previous studies have implemented new fusidic acid (FA) front-loading-dose regimens, allowing higher serum levels than those achievable with ordinary doses. As susceptibility breakpoints are affected by serum level, we evaluated the repurposing of FA as an antimicrobial product against enterococci. FA minimum inhibitory concentrations (MICs) against standard enterococci strains; Enterococcus faecalis ATCC 29212 and Enterococcus faecium ATCC 27270 were 2 and 4 µg/mL, respectively. The MIC against 98 enterococcal clinical isolates was ≤ 8 µg/mL; all would be susceptible if categorized according to recalculated breakpoints (≥ 16 µg/mL), based on the serum level achieved using the front-loading regimen. FA administration in vivo, using the BALB/c mouse infection model, significantly reduced bacterial burden by two to three log10 units in the liver and spleen of mice infected with vancomycin-susceptible and -resistant strains. Exposure of the standard enterococcal strains to increasing, but not fixed, FA concentrations resulted in resistant strains (MIC = 128 µg/mL), with thicker cell walls and slower growth rates. Only one mutation (M651I) was detected in the fusA gene of the resistant strain derived from serial passage of E. faecium ATCC 27270, which was retained in the revertant strain after passage in the FA-free medium. In conclusion, FA can be repurposed as an antimicrobial drug against enterococci with a low probability of mutational resistance development, and can be employed for treatment of infections attributable to vancomycin-resistant enterococci.

Antimicrobial Susceptibility Patterns of Enterococcus Species and Molecular Detection of Enterococcus faecalis Isolated from Patients with Urinary Tract Infection in a Tertiary Care Hospital in Bangladesh

One of the most prevalent infectious diseases identified in both communities and hospitalized patients is urinary tract infection (UTI). Enterococcus is evolved into a clinically pertinent uropathogen due to its evolving resistance to multiple antimicrobial agents.This study, detects antimicrobial susceptibility patterns of Enterococcus species and molecular detection of Enterococcus faecalis from patients with urinary tract infections. In this cross-sectional observational study, 165 urine samples were obtained from clinically diagnosed patients with UTIs of different ages and gender. Enterococcus species were identified by standard microbiological procedure and PCR (by using species-specific primers for Enterococcus faecalis). A modified Kirby Bauer Disc diffusion method was used to identify the antimicrobial susceptibility pattern following Clinical and Laboratory Standards Institute (CLSI) guidelines. Out of 165 urine samples, 134 samples yielded positive cultures. Enterococcus species were isolated from 23 (17.1%) urine samples. Among all Enterococcus, 16 (69.6%) isolates were E. faecalis, detected by PCR assay. A higher (30.4%) proportion of Enterococcus-positive patients were from the age group 48-57 years and female patients (78.2%) had a higher prevalence. Enterococcal infection was found in 56.5% of non-catheterized patients and 43.5% of catheterized patients. Vancomycin and linezolid (78.3%) and meropenem (73.9%) sensitivity was prevalent among all Enterococcus species. They showed 100% resistance towards ceftriaxone, cefixime 95.7%, cefuroxime 91.3%, azithromycin 82.6%. This research indicated the occurrence of Enterococcus species and the advent of multidrug-resistant E. faecalis in patients with UTIs. Routine speciation and antimicrobial susceptibility testing of Enterococcus in various clinical samples is encouraged.

Trends and predictors of antimicrobial resistance among patients with urinary tract infections at a tertiary hospital facility in Alexandria, Egypt: a retrospective record-based classification and regression tree analysis

BACKGROUND

The incidence of Antimicrobial Resistance (AMR) in uropathogens varies between countries and over time. We aim to study the patterns and potential predictors of AMR among patients with UTIs admitted to the Urology Department at Alexandria University Hospital.

METHODS

An observational retrospective record-based study was conducted on all patients admitted to the Urology department from October 2018 to October 2020. Data collected from patients' records included: demographic data, diagnosis on admission, history of chronic diseases, duration of hospital stay, insertion of a urinary catheter, duration of the catheter in days, history of the use of antibiotics in the previous three months, and history of urinary tract operations. If UTI was documented, we abstracted data about urine culture, use of antibiotics, results of urine cultures, type of organism isolated, and sensitivity to antibiotics. We conducted a multivariable logistic regression model. We performed Classification and Regression Tree Analysis (CART) for predicting risk factors associated with drug resistance among patients with UTI. Data were analyzed using SPSS statistical package, Version 28.0, and R software (2022).

RESULTS

This study encompassed 469 patients with UTIs. The most commonly isolated bacterium was Escherichia coli, followed by Klebsiella pneumoniae. Multidrug resistance (MDR) was found in 67.7% (149/220) of patients with hospital-acquired UTIs and in 49.4% (83/168) of patients with community-acquired UTIs. Risk factors independently associated with antimicrobial resistance according to logistic regression analysis were the use of antibiotics within three months (AOR = 5.2, 95% CI 2.19-12.31), hospital-acquired UTI (AOR = 5.7, 95% CI 3.06-10.76), diabetes mellitus (AOR = 3.8, 95% CI 1.24-11.84), age over 60 years (AOR = 2.9, 95% CI 1.27-6.72), and recurrent UTI (AOR = 2.6, 95% CI 1.08-6.20). Classification and regression tree (CART) analysis revealed that antibiotic use in the previous three months was the most significant predictor for developing drug resistance.

CONCLUSION

The study concluded a high level of antimicrobial resistance as well as significant MDR predictors among hospitalized patients with UTIs. It is vital to assess resistance patterns in our hospitals frequently to improve rational antibiotic treatment as well as to sustain antimicrobial stewardship programs and a rational strategy in the use of antibiotics. Empirical therapy for UTI treatment should be tailored to the potential pathogens' susceptibility to ensure optimal treatment. Strategic antibiotic use is essential to prevent further AMR increases. Further research should focus on suggesting new biological systems or designed drugs to combat the resistance of UTI pathogens.

Epidemiology of vancomycin-resistant enterococci in the United Arab Emirates: a retrospective analysis of 12 years of national AMR surveillance data

INTRODUCTION

Enterococci are usually low pathogenic, but can cause invasive disease under certain circumstances, including urinary tract infections, bacteremia, endocarditis, and meningitis, and are associated with peritonitis and intra-abdominal abscesses. Increasing resistance of enterococci to glycopeptides and fluoroquinolones, and high-level resistance to aminoglycosides is a concern. National antimicrobial resistance (AMR) surveillance data for enterococci from the Middle East and North Africa (MENA) and the Gulf region is scarce.

METHODS

A retrospective 12-year analysis of N = 37,909 non-duplicate diagnostic Enterococcus spp. isolates from the United Arab Emirates (UAE) was conducted. Data was generated by routine patient care during 2010-2021, collected by trained personnel and reported by participating surveillance sites to the UAE National AMR Surveillance program. Data analysis was conducted with WHONET.

RESULTS

Enterococcus faecalis was the most commonly reported species (81.5%), followed by Enterococcus faecium (8.5%), and other enterococci species (4.8%). Phenotypically vancomycin-resistant enterococci (VRE) were found in 1.8% of Enterococcus spp. isolates. Prevalence of VRE (%VRE) was highest for E. faecium (8.1%), followed by E. faecalis (0.9%). A significant level of resistance to glycopeptides (%VRE) for these two species has been observed in the majority of observed years [E. faecalis (0-2.2%), 2010: 0%, 2021: 0.6%] and E. faecium (0-14.2%, 2010: 0%, 2021: 5.8%). Resistance to fluoroquinolones was between 17 and 29% (E. faecalis) and was higher for E. faecium (between 42 and 83%). VRE were associated with higher patient mortality (RR: 2.97), admission to intensive care units (RR: 2.25), and increased length of stay (six excess inpatient days per VRE case), as compared to vancomycin-susceptible Enterococcus spp.

DISCUSSION

Published data on Enterococcus infections, in particular VRE-infections, in the UAE and MENA region is scarce. Our data demonstrates that VRE-enterococci are relatively rare in the UAE, however showing an increasing resistance trend for several clinically important antibiotic classes, causing a concern for the treatment of serious infections caused by enterococci. This study also demonstrates that VRE were associated with higher mortality, increased intensive care unit admission rates, and longer hospitalization, thus poorer clinical outcome and higher associated costs in the UAE. We recommend the expansion of current surveillance techniques (e.g., local VRE screening), stricter infection prevention and control strategies, and better stewardship interventions. Further studies on the molecular epidemiology of enterococci are needed.

Antimicrobial Potential of Different Isolates of Chaetomium globosum Combined with Liquid Chromatography Tandem Mass Spectrometry Chemical Profiling

The antimicrobial resistance of pathogenic microorganisms against commercial drugs has become a major problem worldwide. This study is the first of its kind to be carried out in Egypt to produce antimicrobial pharmaceuticals from isolated native taxa of the fungal Chaetomium, followed by a chemical investigation of the existing bioactive metabolites. Here, of the 155 clinical specimens in total, 100 pathogenic microbial isolates were found to be multi-drug resistant (MDR) bacteria. The Chaetomium isolates were recovered from different soil samples, and wild host plants collected from Egypt showed strong inhibitory activity against MDR isolates. Chaetomium isolates displayed broad-spectrum antimicrobial activity against C. albicans, Gram-positive, and Gram-negative bacteria, with inhibition zones of 11.3 to 25.6 mm, 10.4 to 26.0 mm, and 10.5 to 26.5 mm, respectively. As a consecutive result, the minimum inhibitory concentration (MIC) values of Chaetomium isolates ranged from 3.9 to 62.5 µg/mL. Liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) analysis was performed for selected Chaetomium isolates with the most promising antimicrobial potential against MDR bacteria. The LC-MS/MS analysis of Chaetomium species isolated from cultivated soil at Assuit Governate, Upper Egypt (3), and the host plant Zygophyllum album grown in Wadi El-Arbaein, Saint Katherine, South Sinai (5), revealed the presence of alkaloids as the predominant bioactive metabolites. Most detected bioactive metabolites previously displayed antimicrobial activity, confirming the antibacterial potential of selected isolates. Therefore, the Chaetomium isolates recovered from harsh habitats in Egypt are rich sources of antimicrobial metabolites, which will be a possible solution to the multi-drug resistant bacteria tragedy.

Prevalence of Vancomycin-resistant enterococci (VRE) in Egypt (2010-2022): a systematic review and meta-analysis

BACKGROUND

Vancomycin-resistant Enterococci (VRE) represent a critical medical and public health concerns due to their association with serious nosocomial infections and a high risk of mortality. We aimed to reveal the pooled prevalence of VRE and antimicrobial resistance profiles among enterococci clinical isolates in Egypt.

METHODS

A PubMed, Scopus, Google Scholar, and Web of Science literature search was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Only published studies documenting the prevalence of VRE between 2010 and 2022 were included. Using the random effects model and the 95% confidence intervals, the pooled estimate of VRE was calculated by MedCalc Version 20.113. Cochran's Q and I² tests were used to evaluate the degree of heterogeneity, and publication bias was examined by visually examining the funnel plot and its associated tests (Begg's and Egger's tests).

RESULTS

The pooled prevalence of VRE among enterococci clinical isolates in Egypt was estimated to be 26% (95% CI 16.9 to 36.3). E. faecalis had a greater pooled prevalence than E. faecium, with 61.22% (95% CI 53.65 to 68.53) and 32.47% (95% CI 27 to 38.2), respectively. The VanA gene is more frequent than the VanB gene among VRE, with a pooled prevalence of 63.3% (95% CI 52.1 to 73.7) and 17.95% (95% CI 7.8 to 31), respectively. The pooled resistance rate of linezolid was substantially lower than that of ampicillin and high-level gentamicin (HLG) 5.54% (95% CI 2.33 to 10%), 65.7% (95% CI 50.8 to 79.2%), and 61.1% (95% CI 47.4 to 73.9), respectively.

CONCLUSION

The prevalence of VRE is alarmingly high in Egypt. It is imperative that antimicrobial stewardship activities and infection control programs are strictly adhered to and implemented to prevent further escalation of the problem.

Characterization and anti-biofilm activity of bacteriophages against urinary tract Enterococcus faecalis isolates

Strong biofilm-forming Enterococcus feacalis urinary tract pathogens (n = 35) were used to determine the lytic spectrum of six bacteriophages isolated from sewage samples. Only 17 Enterococcus feacalis isolates gave lytic zones with the tested bacteriophages from which five isolates were susceptible to all of them. The isolated enterococcal phages are characterized by wide range of thermal (30–90 °C) and pH (3–10) stability. They belong to order Caudovirales, from which four bacteriophages (EPA, EPB, EPD, EPF) belong to family Myoviridae and two (EPC, EPE) belong to family Siphoviridae. In addition, they have promising antibiofilm activity against the tested strong-forming biofilm E. faecalis isolates. The enterococcal phages reduced the formed and preformed biofilms to a range of 38.02–45.7% and 71.0–80.0%, respectively, as compared to the control. The same promising activities were obtained on studying the anti-adherent effect of the tested bacteriophages on the adherence of bacterial cells to the surface of urinary catheter segments. They reduced the number of adherent cells to a range of 30.8–43.8% and eradicated the pre-adherent cells to a range of 48.2–71.1%, as compared to the control. Overall, the obtained promising antibiofilm activity makes these phages good candidates for application in preventing and treating biofilm associated Enterococcus faecalis infections.

Curcumin assisted green synthesis of silver and zinc oxide nanostructures and their antibacterial activity against some clinical pathogenic multi-drug resistant bacteria

According to WHO warnings, the antibiotic resistance crisis is a severe health issue in the 21st century, attributed to the overuse and misuse of these medications. Consequently, the dramatic spreading rate of the drug-resistant microbial pathogens strains. The microbiological, biochemical tests and antibiotic sensitivity identified the bacteria's multi-drug resistance (MDR). About 150 different clinical samples were taken from hospitalized patients, both males, and females, ranging from 9 to 68 years. Gram-negative strains were (70.0%), while Gram-positive isolates were (30.0%). Among sixteen antibiotics, antibiotic susceptibility of imipenem was found to be the most efficient drug against most of the Gram-negative and Gram-positive isolates, followed by meropenem, depending on the culture and sensitivity results. All the experimental bacteria showed multidrug-resistant phenomena. In this study, green synthesized silver (Cur-Ag NPs) and zinc oxide (Cur-ZnO NPs) nanoparticles in the presence of curcumin extract. In addition, their physicochemical properties have been characterized using different techniques such as UV-Vis spectroscopy, transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and colloidal properties techniques. Furthermore, curcumin-capped silver nanoparticles (AgNPs) exhibited solid antimicrobial action against the experimental bacterial isolates, except Proteus vulgaris (i.e., P. vulgaris). Curcumin-capped zinc oxide nanoparticles (ZnO NPs) found antimicrobial activity against all tested strains. Finally, the minimum inhibitory concentration exhibited values from 3.9 to 15.6 μg ml-1, which is too small compared to other traditional antibiotics. In addition, the green-synthesized Cur-Ag NPs and Cur-ZnO NPs showed good biocompatibility.

Next-Generation Sequencing and MALDI Mass Spectrometry in the Study of Multiresistant Processed Meat Vancomycin-Resistant Enterococci (VRE)

Vancomycin-resistant enterococci (VRE), due to their intrinsic resistance to various commonly used antibiotics and their malleable genome, make the treatment of infections caused by these bacteria less effective. The aims of this work were to characterize isolates of Enterococcus spp. that originated from processed meat, through phenotypic and genotypic techniques, as well as to detect putative antibiotic resistance biomarkers. The 19 VRE identified had high resistance to teicoplanin (89%), tetracycline (94%), and erythromycin (84%) and a low resistance to kanamycin (11%), gentamicin (11%), and streptomycin (5%). Based on a Next-Generation Sequencing NGS technique, most isolates were vanA-positive. The most prevalent resistance genes detected were erm(B) and aac(6')-Ii, conferring resistance to the classes of macrolides and aminoglycosides, respectively. MALDI-TOF mass spectrometry (MS) analysis detected an exclusive peak of the Enterococcus genus at m/z (mass-to-charge-ratio) 4428 ± 3, and a peak at m/z 6048 ± 1 allowed us to distinguish Enterococcus faecium from the other species. Several statistically significant protein masses associated with resistance were detected, such as peaks at m/z 6358.27 and m/z 13237.3 in ciprofloxacin resistance isolates. These results reinforce the relevance of the combined and complementary NGS and MALDI-TOF MS techniques for bacterial characterization.

Prevalence of Multidrug-Resistant Enterococcus faecalis in Hospital-Acquired Surgical Wound Infections and Bacteremia: Concomitant Analysis of Antimicrobial Resistance Genes

Background:

The study aimed to assess the prevalence of Enterococcus faecalis infections among patients with hospital-acquired surgical wound sepsis and bacteremia in surgical wards and identify the antimicrobial susceptibility in these pathogens. Genetic role of erythromycin, vancomycin, and cephalosporin resistance in these pathogens was also examined.

Methods:

Two hundred samples were collected from surgical wound infections and 100 blood cultures from patients with suggested bacteremia to identify E faecalis by phenotypic and genotypic methods. Antimicrobial susceptibility to 12 antimicrobial agents was tested. The presence of resistance genes was examined by polymerase chain reaction (PCR) assay.

Results:

E faecalis was isolated with a frequency of 24/200 (12%) from surgical wound samples and 2/100 (2%) from blood cultures. All isolates were completely resistant to cefepime, ampicillin, and tetracycline, 96% of isolates were resistant to erythromycin, 53.8% to vancomycin, and 23.1% to linezolid. Multidrug resistance (MDR) was found in 100% of isolates. ere(B) and erm(B) genes were present in 20/25 (80%) and 17/25 (68%) of erythromycin-resistant isolates, respectively, 15 (60%) isolates carry both ere(B) and erm(B) genes. Van A gene was detected in 71.4% of vancomycin-resistant isolates. All isolates were negative for mef(A/E), blaSHV, and blaTEM genes.

Conclusion:

MDR in all isolates (100%) and high-level resistance to gentamicin, erythromycin, and vancomycin were reported in E Faecalis isolates. In the studied isolates, erythromycin resistance mainly related to the presence of ere(B) and erm(B) genes and vancomycin resistance was mainly related to the presence of vanA gene.

High prevalence of vancomycin and high-level gentamicin resistance in Enterococcus faecalis isolates

Multiple drug-resistant enterococci are major cause of healthcare-associated infections due to their antibiotic resistance traits. Among them, Enterococcus faecalis is an important opportunistic pathogen causing various hospital-acquired infections. A total of 53 E. faecalis isolates were obtained from various infections. They were identified by phenotypic and genotypic methods. Determination of antimicrobial resistance patterns was done according to CLSI guidelines. The isolates that were non-susceptible to at least one agent in ≥3 antimicrobial categories were defined as multidrug-resistant (MDR). Detection of antimicrobial resistance genes was performed using standard procedures. According to MDR definition, all of the isolates were MDR (100%). High-level gentamicin resistance was observed among 50.9% of them (MIC ≥ 500 μg/ml). The distributions of aac(6')-Ie-aph(2'')-Ia and aph(3')-IIIa genes were 47.2% and 69.8%, respectively. The aph(2'')-Ib, aph(2'')-Ic, aph(2'')-Id, and ant(4')-Ia genes were not detected. Vancomycin resistance was found in 45.3% of strains. The vanA gene was detected in 37.7% of isolates, whereas vanB and vanC₁ genes were not observed in any strain. Erythromycin resistance rate was 79.2% and the frequencies of ermB and ermC genes were 88.6% and 69.8%, respectively. The ermA and msrA genes were not present in any of the isolates. Our data indicate a high rate of MDR E. faecalis strains. All of high-level gentamicin-resistant isolates carried at least one of aac(6')-Ie-aph(2'')-Ia or aph(3')-IIIa genes. Distribution of vanA was notable among the isolates. In addition, ermB and ermC were accountable for resistance to erythromycin.

Development of a melting-curve based multiplex real-time PCR assay for simultaneous detection of Streptococcus agalactiae and genes encoding resistance to macrolides and lincosamides

Background

Streptococcus agalactiae or Group B Streptococcus (GBS) remains the leading cause of infections in newborns worldwilde. Prenatal GBS screening of pregnant women for vaginal-rectal colonization is recommended in many countries to manage appropriate intrapartum antimicrobial prophylaxis for those identified as carriers. In this study, a novel melting-curve based multiplex real-time PCR assay for the simultaneous detection of GBS and macrolide and lincosamide resistance markers was developed. The usefulness of the assay was evaluated for rapid and accurate prenatal GBS screening.

Methods

One hundred two pregnant women who were at 35–37 weeks of gestation were enrolled in this study. The analytical performance of the multiplex real-time PCR was first tested using a panel of reference and clinical bacterial and fungal strains. To test the clinical performance, vaginal-rectal swabs were obtained from pregnant women who were seen at the teaching hospital for regular prenatal care. The results of real-time were compared with those obtained from microbiological analyses.

Results

The real-time PCR assay showed 100% specificity and a limit of detection of 10⁴ colony forming units equivalent per reaction. The prevalence of GBS colonization among the population studied was 15.7% (16/102) based on a positive culture and the real-time PCR results. Agreement between the two assays was found for 11 (68.75%) GBS colonized women. Using the culture-based results as a reference, the multiplex real-time PCR had a sensitivity of 91.7% (11/12, CI 59.7–99.6%), a specificity of 95.5% (86/90, CI 89.8–98.7%), a positive predictive value of 73.3% (11/15, CI 44.8–91.1%) and a negative predictive value of 98.9% (86/87, CI 92.9–99.9%).

Conclusion

The multiplex real-time PCR is a rapid, affordable and sensitive assay for direct detection of GBS in vaginal-rectal swabs.

Electronic supplementary material

The online version of this article (10.1186/s12884-018-1774-5) contains supplementary material, which is available to authorized users.