Vancomycin-resistant Enterococcus Spp Research Articles

Prevalence of Vancomycin-Resistant Enterococcus spp. Isolates in Southeast Iran, Zahedan

Background: Enterococci are clinically significant, especially in individuals with compromised immune systems, which are recognized as a critical contributor to nosocomial infections. Objectives: This study aimed to determine antibiotic susceptibility profiles and vancomycin-resistance Enterococcus (VRE) isolates in Zahedan, Iran. Methods: A hospital-based cross-sectional study was conducted at Ali Ibne Abi Talib Hospital from March 2019 to February 2022. Clinical samples included urine, blood, abscesses and other body fluids from patients referred to this hospital during the study period. A total of 3000 patients were included in the study, and the Kirby-Bauer method was used to test isolates identified by morphological and biochemical characteristics for antibiotic susceptibility. Data were analyzed using SPSS software version 20. P-values < 0.05 were considered statistically significant. Results: Out of 3000 culture-positive clinical samples comprised of 82 urine, ten blood, one tracheal, two wound, and one pulmonary isolate, were identified as Enterococcus faecalis (69.1%), Enterococcus faecium (7.3%), and Enterococcus spp. (23.6%). Moreover, two-thirds of isolates were multidrug-resistant (MDR). Although 66.7% and 63.9% were sensitive to nitrofurantoin and linezolid, resistance to ciprofloxacin (74.2%) and ampicillin (65.9%) was frequently observed. Nitrofurantoin or linezolid were the only effective antibiotics for UTIs. In addition, 50% of isolates were resistant to vancomycin. Conclusions: Based on the results, a combination of vancomycin/or linezolid and nitrofurantoin for urine infections was effective against Enterococci in this clinical center. Nevertheless, continuous and frequent surveillance for resistance patterns is necessary for the reasonable and evidence-based use of antibiotics.

Blood Stream Infections in COVID-19 Patients From a Tertiary Care Center in Lebanon: Causative Pathogens and Rates of Multi-Drug Resistant Organisms

ObjectiveTo report the microbiological profile of the pathogens implicated in blood stream infections (BSI) in hospitalized coronavirus disease 2019 (COVID-19) patients and to examine the risk factors associated with multidrug-resistant organisms (MDROs) causing BSI. Patients and MethodsBetween March 2020 and September 2021, 1647 patients were hospitalized with COVID-19 at the American University of Beirut. From 85 patients, 299 positive blood cultures were reported to the Infection Control and Prevention Program. The BSI was defined as 1 positive blood culture for bacterial or fungal pathogens. The following organisms were considered MDROs: methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus spp, carbapenem-resistant Enterobacterales spp., carbapenem-resistant Pseudomonas aeruginosa, MDR Acinetobacter baumannii only susceptible to colistin or tigecycline, and Candida auris. ResultsWe identified 99 true positive BSI events. Gram-negative bacteria accounted for 38.4 %, followed by Gram-positive bacteria (37.4%), and fungi (24.2%). The most isolated species were Candida spp. (23%), 3 of which were C. auris, followed by Enterobacterales spp. (13%), Enterococcus spp. (12%), S. aureus (9%), P. aeruginosa (9%), and A. baumannii (3%). The MDROs represented 26% of the events. The overall mortality rate was 78%. The time to acquisition of BSI in patients with MDROs was significantly longer compared with that of non-MDROs (20.2 days vs 11.2 days). And there was a significantly shorter time from acquisition of BSI to mortality between MDROs and non-MDROs (1.5 vs 8.3 days). ConclusionRigorous infection prevention and control measures and antimicrobial stewardship are important to prevent antimicrobial resistance progression, especially in low-resource settings.

Riboflavin-Vancomycin Conjugate Enables Simultaneous Antibiotic Photo-Release and Photodynamic Killing against Resistant Gram-Positive Pathogens.

Decades of antibiotic misuse have led to alarming levels of antimicrobial resistance, and the development of alternative diagnostic and therapeutic strategies to delineate and treat infections is a global priority. In particular, the nosocomial, multidrug-resistant "ESKAPE" pathogens such as Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus spp (VRE) urgently require alternative treatments. Here, we developed light-activated molecules based on the conjugation of the FDA-approved photosensitizer riboflavin to the Gram-positive specific ligand vancomycin to enable targeted antimicrobial photodynamic therapy. The riboflavin-vancomycin conjugate proved to be a potent and versatile antibacterial agent, enabling the rapid, light-mediated, killing of MRSA and VRE with no significant off-target effects. The attachment of riboflavin on vancomycin also led to an increase in antibiotic activity against S. aureus and VRE. Simultaneously, we evidenced for the first time that the flavin subunit undergoes an efficient photoinduced bond cleavage reaction to release vancomycin, thereby acting as a photoremovable protecting group with potential applications in drug delivery.

Vancomycin-Resistant Enterococcus spp. Isolated From Mastitic cow’s milk

Vancomycin-Resistant Enterococcus spp. Isolated From Mastitic cow’s milk

1194. Efficacy of shortened high-level disinfection (HLD) protocols for GI duodenoscopes with disposable tips used for endoscopic retrograde cholangiopancreatography (ERCP)

Abstract Background The most efficient combination of manual washes (MW) and high-level disinfection (HLD) cycles for the reprocessing of duodenoscopes used for ERCP is unknown. The FDA recently announced the national recommendation for transition to duodenoscopes with disposable components. Methods We studied contamination of Pentax Medical duodenoscopes with disposable tips used for ERCP. Duodenoscopes were cleaned and disinfected following removal of the disposable tip. First, one manual wash was performed with detergent and brushes that fit into the suction channel, air/water valves, cylinder, and elevator chamber. Afterward, the duodenoscope underwent HLD with an automated endoscope re-processor. Our study evaluated the success of an abbreviated cycle of one MW followed by one HLD (MW-HLD) cycle compared to a pair of MW-HLD cycles. Each duodenoscope was sampled in 4 locations after the first MW-HLD cycle and the second: 1) The elevator tab, 2) elevator channel distal opening, 3) composite duodenoscope tip, and 4) the elevator channel (Figure 1). Samples 1-3 were collected with flocked swabs. Swabs were plated on routine medias for relevant enteric pathogens. The 4th was collected by flushing 25 mL of neutralizing buffer through the elevator channel, then scrubbing the channel with a brush, followed by another 25 mL flush. The 50 mL eluent was vacuum filtered through a 0.22-micron filter and plated on TSA. Antibiotic resistance was assessed via PCR. CFU and proportion of contaminated scopes were compared between MW-HLD cycles. Results 46 duodenoscopes were sampled from September 2021 through March 2022 resulting in 92 sample events and 368 total samples. After one MW-HLD cycle, 19 of 46 (41%) duodenoscopes remained contaminated, including 5 (11%) with VRE (Table 1). After two MW-HLD cycles, 11 (24%) remained contaminated and 0 (0%) with VRE (p=0.08, 0.02, respectively). Results were similar at the sample location level (p=0.03, 0.01, respectively). Proportion of duodenoscopes contaminated with any flora and Vancomycin-resistant Enterococcus spp. Conclusion Our data demonstrate that 1 MW-HLD cycle is insufficient at decontaminating duodenoscopes with disposable tips but do support the use of two MW-HLD cycles. VRE was identified after one MW- HLD cycle, but not after two MW-HLD cycles. Further studies are needed to determine the optimal combination of MWs and HLDs while minimizing HLD staff time. Disclosures All Authors: No reported disclosures.

1223. The Impact of the COVID-19 Pandemic on the Prevalence of Multidrug-resistant Organisms in Veterans Affairs Nursing Homes

Abstract Background Multidrug-resistant organisms (MDRO) in long-term care facilities are prevalent and pose a major health concern for their residents. During the COVID-19 pandemic, infection control measures were justifiably heightened in every aspect of health care, including nursing homes. There are reports depicting decreasing prevalence of MDRO in hospital settings during the pandemic. We compared the prevalence of MDRO in our facility’s nursing homes in the two-year period before vs. the two years of the pandemic. Methods Northport Veterans Affairs Medical Center provides long-term nursing home care structured as community living centers including mental health and hospice care; a 139 total bed capacity. A retrospective review of culture data collected by infection control preventionists comparing the prevalence of MDROs between 1 March 2018 to 28 February 2022 was performed. Data included: Nasopharyngeal MRSA swabs, urine, wound, blood, sputum cultures, C. difficile toxin and PCR assays. MDRO included ESBL E. coli, K. pneumoniae, P. mirabilis, MDR Pseudomonas spp (resistance to 2/3 antibiotics: cefepime/piperacillin-tazobactam/ciprofloxacin), carbapenem-resistant Pseudomonas spp, and vancomycin-resistant Enterococcus spp. Results There were 75209 bed days of care from 1 March 2018 to 28 February 2020 vs. 77531 from 1 March 2020 to 28 February 2022. The MRSA rate per 1000 patient days decreased from 4.98 pre-COVID to 2.70 during-COVID, P < 0.001. Similarly, there was a decrease in C. difficile 0.69 vs. 0.13, P< 0.001, ESBL E. coli 0.53 vs. 0.51, P< 0.001 and S. maltophilia (no cases during COVID). There was an increase in ESBL K. pneumoniae 0.51 vs. 0.63, P< 0.001, MDR Pseudomonas 0.05 vs. 0.49, P< 0.001, carbapenem-resistant Pseudomonas 0.026 vs. 0.077, P< 0.001 and VRE 0.22 vs. 0.31, P< 0.001. There were no Candida auris or Acinetobacter spp detected in the study period. MDRO occurrences before and during COVID-19 pandemic Conclusion While increased awareness and implementation of infection control measures during the years of the COVID-19 pandemic led to decrease in certain infections in our nursing homes, like C. difficile, a surprising uptick in ESBL K. pneumoniae and MDR Pseudomonas was noted. This is a concerning trend that merits further study to identify molecular factors and increase stewardship efforts in diligent use of carbapenems. Disclosures All Authors: No reported disclosures.

Time to Effective Therapy Is an Important Determinant of Survival in Bloodstream Infections Caused by Vancomycin-Resistant Enterococcus spp.

Enterococcal bloodstream infections (EBSI) caused by vancomycin-resistant enterococci (VRE) are associated with a significant rate of unfavorable outcomes. No definitive data have been reported about the association between delayed antibiotic therapy and mortality. In this prospective observational study in three large hospitals in Italy (from August 2016 to April 2021), all consecutive hospitalized patients with a confirmed diagnosis of hospital-acquired monomicrobial BSI caused by VRE—with no evidence of endocarditis—were analyzed. Cox regression analysis showed that risk factors independently associated with 30-day mortality were age (HR 2.98, CI95% 1.44–6.81, p = 0.002), chronic kidney disease (HR 5.21, CI95% 1.48–22.23, p = 0.001), oncologic disease (HR 2.81, CI95% 1.45–19.8, p = 0.005), and intensive care unit admission (HR 3.71, CI95% 2.23–7.99, p < 0.001). Conversely, early effective therapy was associated with survival (HR 0.32, CI95% 0.38–0.76, p < 0.001). The administration of early effective antibiotic therapy within 48 h from blood culture collection was associated with 30-day mortality rates lower than 33%. Time from blood culture collection to appropriate therapy was an independent predictor of 30-day mortality in patients with EBSI caused by VRE. Based on these data, clinicians should start effective antibiotic therapy as soon as possible, preferably within the first 48 h from blood culture collection. Treatment strategies allowing the early delivery of in vitro active antibiotics are urgently needed, especially in critically ill patients at risk of VRE bacteremia.

Predictors of Vancomycin-Resistant Enterococcus spp. Intestinal Carriage among High-Risk Patients in University Hospitals in Serbia.

The predictors of intestinal carriage of vancomycin-resistant Enterococcus spp. (VRE) among high-risk patients in the counties of the Southeast Europe Region are insufficiently investigated, yet they could be of key importance in infection control. The aim of the study was to identify risk factors associated with fecal VRE colonization among high-risk inpatients in university hospitals in Serbia. The study comprised 268 inpatients from three university hospitals. Data on patient demographics and clinical characteristics, length of hospital stay, therapy, and procedures were obtained from medical records. Chi-squared tests and univariate and multivariate logistic regressions were performed. Compared to the hemodialysis departments, stay in the geriatric departments, ICUs, and haemato-oncology departments increased the risk for VRE colonization 7.6, 5.4, and 5.5 times, respectively. Compared to inpatients who were hospitalized 48 h before stool sampling for VRE isolation, inpatients hospitalized 3–7, 8–15, and longer than 16 days before sampling had 5.0-, 4.7-, and 6.6-fold higher risk for VRE colonization, respectively. The use of cephalosporins and fluoroquinolones increased the risk for VRE colonization by 2.2 and 1.9 times, respectively. The age ≥ 65 years increased the risk for VRE colonization 2.3 times. In comparison to the University Clinical Centre of Serbia, the hospital stays at Zemun and Zvezdara University Medical Centres were identified as a protector factors. The obtained results could be valuable in predicting the fecal VRE colonization status at patient admission and consequent implementation of infection control measures targeting at-risk inpatients where VRE screening is not routinely performed.

Causative agents of bloodstream infections in two Croatian hospitals and their resistance mechanisms

Blood samples were collected alongside with routine blood cultures (BC) from patients with suspected sepsis, to evaluate the prevalence of different causative agents in patients with bacteraemia. Among 667 blood samples, there were 122 positive BC (18%). Haemoglobin content, platelet number, and systolic blood pressure values were significantly lower in patients with positive BC, whereas serum lactate levels, CRP, creatinine and urea content were significantly higher in patients with positive BC. The rate of multidrug (MDR) or extensively drug resistant (XDR) bacteria was 24% (n = 29): Klebsiella pneumoniae (9), Pseudomonas aeruginosa (9), Acinetobacter baumannii (4), Escherichia coli (1), vancomycin resistant Enterococcus spp (VRE) (3), and methicillin-resistant Staphylococcus aureus MRSA (3). The dominant resistance mechanisms were the production of extended-spectrum β-lactamases, OXA-48 carbapenemase, and colistin resistance in K. pneumoniae, VIM metallo-β-lactamases in P. aeruginosa and OXA-23-like oxacillinases in A. baumannii. The study revealed high rate of MDR strains among positive BCs in Zagreb, Croatia.

62. Secondary Prophylaxis in Clostridioides difficile Infections: a Closer Look at Outcomes

Background Clostridioides difficile infection (CDI) is an urgent public threat and carries a 25% chance of recurrence (rCDI). Data on safety and efficacy of oral vancomycin prophylaxis (OVP) in reducing rCDI is limited. We implemented a best practice advisory (BPA) to alert the prescriber and antibiotic stewardship (ASP) team for patients with CDI in the previous 60 days being initiated on systemic antimicrobials. The alert states “Don’t use antibiotics in patients with recent CDI without convincing evidence of need. Antibiotics pose a high risk of recurrence”. ASP team would recommended OVP if antibiotics are continued. This study evaluated the impact of the BPA alert on OVP prescribing and patient outcomes.MethodsIRB approved, retrospective, observational cohort study comparing patients who received OVP to no OVP. Inclusion: adults with history of laboratory confirmed CDI, ≥ 14 days post-CDI treatment completion, BPA from 3/7/19 – 3/31/20, receiving non-CDI systemic antimicrobials, and without history of bezlotoxumab infusion. Data were reported using descriptive statistics and bivariate analysis. Primary endpoint: rCDI within 2-8 weeks post-OVP completion. Secondary endpoints: vancomycin-resistant Enterococcus spp (VRE) in clinical culture post-OVP and 1-year mortality. Results70 patients included: 32 (46%) no-OVP and 38 (54%) OVP. Baseline characteristics, previous CDI treatment, and outcomes were similar (Table 1). Index CDI was severe in the OVP group (18, 47% vs. 9, 28%). Median Charlson comorbidity index: 7 (3 – 9) no-OVP and 7 (5 – 9) OVP. OVP regimens, 125 mg by mouth: once daily 4 (10%), twice daily 22 (58%), and every 6 hours 12 (32%). Median prophylaxis duration: 10 days (6 – 13). rCDI occurred in 3 (9%) no-OVP and 2 (5%) OVP (P = 0.654). Mortality: 10 (31%) no-OVP and 16 (42%) OVP (P = 0.458). Table 1. Patient Characteristics and Endpoints ConclusionOVP was utilized in approximately half of patients who required non-CDI antibiotics. Efficacy interpretation is limited by inconsistent dosing regimens and significant comorbid illness in the cohort. Future work will focus on further optimizing the BPA and standardizing the OVP regimen. Disclosures Rachel Kenney, PharmD, Medtronic, Inc. (Other Financial or Material Support, spouse is an employee and shareholder) Susan L. Davis, PharmD, Nothing to disclose

A randomized controlled trial of Lactobacillus rhamnosus GG on antimicrobial-resistant organism colonization.

Alteration of the colonic microbiota following antimicrobial exposure allows colonization by antimicrobial-resistant organisms (AROs). Ingestion of a probiotic, such as Lactobacillus rhamnosus GG (LGG), could prevent colonization or infection with AROs by promoting healthy colonic microbiota. The purpose of this trial was to determine the effect of LGG administration on ARO colonization in hospitalized patients receiving antibiotics. Prospective, double-blinded, randomized controlled trial of LGG versus placebo among patients receiving broad-spectrum antibiotics. Tertiary care center. In total, 88 inpatients receiving broad-spectrum antibiotics were enrolled. Patients were randomized to receive 1 capsule containing 1×1010 cells of LGG twice daily (n = 44) or placebo (n = 44), stratified by ward type. Stool or rectal-swab specimens were collected for culture at enrollment, during admission, and at discharge. Using selective media, specimens were cultured for Clostridioides difficile, vancomycin-resistant Enterococcus spp (VRE), and antibiotic-resistant gram-negative bacteria. The primary outcome was any ARO acquisition. Secondary outcomes included loss of any ARO if colonized at enrollment, and acquisition or loss of individual ARO. ARO colonization prevalence at study enrollment was similar (LGG 39% vs placebo 39%). We detected no difference in any ARO acquisition (LGG 30% vs placebo 33%; OR,1.19; 95% CI, 0.38-3.75) nor for any individual ARO acquisition. There was no difference in the loss of any ARO (LGG 18% vs placebo 24%; OR, 1.44; 95% CI, 0.27-7.68) nor for any individual ARO. LGG administration neither prevented acquisition of ARO nor accelerated loss of ARO colonization.

238. Novel Way to Evaluate Antibiotic Use Appropriateness: Moving Towards the “Never Event” Classification by Electronic Algorithm

BackgroundAntibiotic use is commonly tracked electronically by antimicrobial stewardship programs (ASPs). Traditionally, evaluating the appropriateness of antibiotic use requires time- and labor-intensive manual review of each drug order. A drug-specific “appropriateness” algorithm applied electronically would improve the efficiency of ASPs. We thus created an antibiotic “never event” (NE) algorithm to evaluate vancomycin use, and sought to determine the performance characteristics of the electronic data capture strategy.MethodsAn antibiotic NE algorithm was developed to characterize vancomycin use (Figure) at a large academic institution (1/2016–8/2019). Patients were electronically classified according to the NE algorithm using data abstracted from their electronic health record. Type 1 NEs, defined as continued use of vancomycin after a vancomycin non-susceptible pathogen was identified, were the focus of this analysis. Type 1 NEs identified by automated data capture were reviewed manually for accuracy by either an infectious diseases (ID) physician or an ID pharmacist. The positive predictive value (PPV) of the electronic data capture was determined.Antibiotic Never Event (NE) Algorithm to Characterize Vancomycin Use ResultsA total of 38,774 unique cases of vancomycin use were available for screening. Of these, 0.6% (n=225) had a vancomycin non-susceptible pathogen identified, and 12.4% (28/225) were classified as a Type 1 NE by automated data capture. All 28 cases included vancomycin-resistant Enterococcus spp (VRE). Upon manual review, 11 cases were determined to be true positives resulting in a PPV of 39.3%. Reasons for the 17 false positives are given in Table 1. Asymptomatic bacteriuria (ASB) due to VRE in scenarios where vancomycin was being appropriately used to treat a concomitant vancomycin-susceptible infection was the most common reason for false positivity, accounting for 64.7% of false positive cases. After removing urine culture source (n=15) from the algorithm, PPV improved to 53.8%.ConclusionAn automated vancomycin NE algorithm identified 28 Type 1 NEs with a PPV of 39%. ASB was the most common cause of false positivity and removing urine culture as a source from the algorithm improved PPV. Future directions include evaluating Type 2 NEs (Figure) and prospective, real-time application of the algorithm.DisclosuresMarc H. Scheetz, PharmD, MSc, Merck and Co. (Grant/Research Support)

Oral vancomycin prophylaxis against recurrent Clostridioides difficile infection: Efficacy and side effects in two hospitals.

The data regarding the effectiveness of chemical prophylaxis against recurrent C. difficile infection (CDI) remain conflicting. Retrospective cohort study on the effectiveness of oral vancomycin for prevention of recurrent CDI. Two academic centers in New York. Two participating hospitals implemented an automated alert recommending oral vancomycin 125 mg twice daily in patients with CDI history scheduled to receive systemic antimicrobials. Measured outcomes included breakthrough and recurrent CDI rates, defined as CDI during and 1 month after initiation of prophylaxis, respectively. A self-controlled, before-and-after study design was employed to examine the effect of vancomycin prophylaxis on the prevalence of vancomycin-resistant Enterococcus spp (VRE) colonization and infection. We included 264 patients in the analysis. Breakthrough CDI was identified in 17 patients (6.4%; 95% confidence interval [CI], 3.8%-10.1%) and recurrent in 22 patients (8.3%; 95% CI, 5.3%-12.3%). Among the 102 patients with a history of CDI within the 3 months preceding prophylaxis, 4 patients (3.9%; 95% CIs, 1.1%-9.7%) had breakthrough CDI and 9 had recurrent disease (8.8%; 95% CIs, 4.1%-16.1%). In the 3-month period following vancomycin prophylaxis, we detected a statistically significant increase in both the absolute number of VRE (χ2, 0.003) and the ratio of VRE to VSE isolates (χ2, 0.003) compared to the combined period of 1.5 months preceding and the 3-4.5 months following prophylaxis. This effect persisted 6 months following prophylaxis. Prophylactic vancomycin is an effective strategy to prevent CDI recurrence, but it increases the risk of VRE colonization. Thus, a careful selection of patients with high benefit-to-risk ratio is needed for the implementation of this preventive policy.

Companion psittacine birds as reservoir of gentamicin and vancomycin-resistant Enterococcus spp.

ABSTRACT: Enterococcus are recognized worldwide as significant nosocomial agents that have been continuously envolving to adapt to different niches and acquire resistance to several antibiotic classes. Vancomycin and gentamicin-resistant strains of E. faecalis and E. faecium have been associated with nosocomial human infections. Some epidemiological studies suggest the participation of pets as reservoirs of vancomycin and gentamicin-resistant Enterococcus strains. However, the role of companion birds as reservoirs of these strains has been poorly studied. In this study, 126 psittacine birds were evaluated and 26.9% carried Enterococcus spp., including the species E. faecalis, E. faecium, E. hirae, E. phoeniculicola, E. gallinarum and E. casseliflavus. The antibiotic resistance profile showed four high-level gentamicin-resistance (HLGR) strains. In addition, two strains presented intermediate levels of vancomycin resistance. Resistant strains were isolated from fecal and oropharynx samples of sick and clinically healthy birds, suggesting that psittacine birds may act as reservoirs of HLGR Enterococcus spp. However, sick birds appear to be more implicated in the enterococci transmission than healthy birds.

Antibiotic-resistant indicator bacteria in irrigation water: High prevalence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli.

Irrigation water is a major source of fresh produce contamination with undesired microorganisms including antibiotic-resistant bacteria (ARB), and contaminated fresh produce can transfer ARB to the consumer especially when consumed raw. Nevertheless, no legal guidelines exist so far regulating quality of irrigation water with respect to ARB. We therefore examined irrigation water from major vegetable growing areas for occurrence of antibiotic-resistant indicator bacteria Escherichia coli and Enterococcus spp., including extended-spectrum β-lactamase (ESBL)-producing E. coli and vancomycin-resistant Enterococcus spp. Occurrence of ARB strains was compared to total numbers of the respective species. We categorized water samples according to total numbers and found that categories with higher total E. coli or Enterococcus spp. numbers generally had an increased proportion of respective ARB-positive samples. We further detected high prevalence of ESBL-producing E. coli with eight positive samples of thirty-six (22%), while two presumptive vancomycin-resistant Enterococcus spp. were vancomycin-susceptible in confirmatory tests. In disk diffusion assays all ESBL-producing E. coli were multidrug-resistant (n = 21) and whole-genome sequencing of selected strains revealed a multitude of transmissible resistance genes (ARG), with blaCTX-M-1 (4 of 11) and blaCTX-M-15 (3 of 11) as the most frequent ESBL genes. Overall, the increased occurrence of indicator ARB with increased total indicator bacteria suggests that the latter might be a suitable estimate for presence of respective ARB strains. Finally, the high prevalence of ESBL-producing E. coli with transmissible ARG emphasizes the need to establish legal critical values and monitoring guidelines for ARB in irrigation water.

New colony multiplex PCR assays for the detection and discrimination of vancomycin-resistant enterococcal species

New colony multiplex PCR assays for detection of seven types of vancomycin-resistance determinants and eight types of Enterococcus species were developed. For 135 enterococcal isolates examined in this study, these assays showed high sensitivity and specificity, and could provide the rapid and accurate detection of vancomycin-resistant determinants and Enterococcus spp.

Isolation of Multidrug Resistant Bacteria from Patients Medical Charts.

Patient's medical charts in hospitals are potentially contaminated by pathogenic bacteria and might act as vehicles for transmission of bacterial infections.This study was aimed to determine the rate of contamination of medical charts by multidrug resistant bacteria. Sampling of total 250 patient's medical charts from different wards was done with the help of cotton swabs soaked in sterile normal saline. The swabs thus collected were cultured using standard microbiological procedures.The colonies grown were then identified with the help of colony morphology, Gram's stain and biochemical tests. Antimicrobial susceptibility testing was performed by using Kirby-Bauer disc diffusion technique. Of the total 250 charts sampled, 98.8% grew bacteria; Bacillus spp. in 40.7%, followed by Staphylococcus aureus (17%), coagulase-negative Staphylococcus spp.(CoNS) (17%), Citrobacter freundii (9.6%) and Acinetobacter spp. (4.5%). Rate of multidrug resistance was highest in Acinetobacter spp. (50%). Among 83 isolates of S. aureus, methicillin resistance was found in 29 isolates. Similarly, two out of total 9 isolates of Enterococcus spp. were vancomycin resistant. This study showed that patient's medical charts were contaminated with multidrug resistant bacteria including methicillin resistant S. aureus and vancomycin resistant Enterococcus spp. Strict hand washing before and after handling medical charts is recommended.

Genotypic Characterization of Vancomycin-Resistant Enterococcus spp. In Tertiary Center, Iran.

Enterococci infection rate, mortality and morbidity have been increased in recent decades accompanied by progressive emerging antimicrobial resistance. Vancomycin-resistant enterococci (VRE), important pathogen in hospitalized patients, has distinct antibiotic susceptibility to glycopeptides that varied genetically and can influence in choosing therapeutic agents. In this study, we aimed to determine the patterns of antimicrobial resistance according to the genotypic variations in VREs. Enterococci samples were isolated from different clinical specimens followed by antimicrobial susceptibility that was determined by the disk diffusion method during one year 2015-2016. Subsequently, VREs were selected and extraction of total DNA was performed using the QIAmp DNA mini kit. The eight oligonucleotide primer pairs were used to amplify the genes vanA, vanB, vanC1, vanC2, vanC2/3, esp, and hyl. Multiplex polymerase chain reaction (PCR) was performed to identify Van A, Van B, Van C, Van D and clonal complex 17 (CC17). A total of 235 enterococci were isolated, including 121 and 114 Enterococcus faecalis and Enterococcus faecium, respectively. Most of VREs (42% of all enterococci) were E. faecium (91.1% vs. 8.9% E. faecalis). All VREs had Van A; and Van B, Van C and Van D genes were not found in any isolates. The frequency rate of CC17, genetic subset of E. faecium, was 68.3%. In conclusion, we can assume that the most frequent genotype of VRE in our country is VAN A and literally, the other genotypes.

Ampicillin for the treatment of complicated urinary tract infections caused by vancomycin–resistant Enterococcus spp (VRE): a single-center university hospital experience

Vancomycin-resistant enterococci (VRE) are a common cause of urinary tract infections (UTIs) and are typically multidrug resistant, including ampicillin. This retrospective study evaluated outcomes of 84 adult patients hospitalized between January 2007 and December 2015 with ampicillin– and vancomycin–resistant enterococcus isolates causing UTI and treated with ampicillin. Treatment response was classified as clinical cure and microbiological eradication. Clinical cure was achieved in 88.1% (74/84) of patients. In patients with follow–up cultures, microbiological eradication was achieved in 86% (50/58) of patients. Cure rates were similar in patients with indwelling urinary catheters (n = 45) receiving catheter exchange/removal (90.47%; 19/21) versus catheter retention (87.5%; 21/24). Presence of co–morbidities, such as diabetes and chronic kidney disease, were not associated with increased risk of treatment failure. Immunocompromised patients achieved lower cure rates of 78.1% (25/32) compared with 94.2% (49/52) among those without immune impairment (P = 0.038). Presence of an underlying urinary tract abnormality was also associated with a lower cure rate of 71.4% (15/21) compared with 93.7% (59/63) in those without urinary tract abnormalities (P = 0.0135). Overall cure rates remained high in all groups providing good evidence to support ampicillin for the treatment of complicated UTI caused by ampicillin– and vancomycin–resistant enterococci.

VanA-positive multi-drug-resistant Enterococcus spp. isolated from surfaces of a US hospital laundry facility

Enterococcus spp. are a normal part of the gastrointestinal tract of humans and animals. They are also important pathogens, being responsible for 14% of US nosocomial infections from 2007 to 2010. To examine a laundry facility that processes clinical linens for the presence and seasonality of vancomycin-resistant Enterococcus spp. Surface samples were collected four times in 2015 from the dirty and clean areas of the laundry facility. Isolates were confirmed using biochemical assays, and antibiotic susceptibility testing was performed. Further investigations included molecular characterization by multi-locus sequence typing (MLST), detection of acquired vanA and vanB and/or intrinsic vanC1 genes by polymerase chain reaction, and eBURST analysis. Seventy-four vanA-positive multi-drug-resistant Enterococcus spp. were identified: 64/120 (53%) in the dirty area and 10/120 (8%) in the clean area. There were 14 ST types among the E.faecium isolates identified (ST16, 17, 18, 117, 186, 280, 324, 412, 584, 664, 665, 736, 750 and 1038). Both E.faecalis isolates were ST109. Isolation of vancomycin-resistant enterococci (VRE) isolates was significantly higher (53% vs 8%) in the dirty area of the facility compared with the clean area. This is the first study to examine an industrial laundry facility for the presence of VRE, and may be an unrecognized reservoir.