• Food Science of Animal Resources
• /
• v.38 no.5
• /
• pp.1064-1079
• /
• 2018

In this study, the antimicrobial activity of a bacteriocin produced by Enterococcus faecalis KT11, isolated from traditional Kargı Tulum cheese, was determined, and bacteriocin KT11 was partially characterized. The results showed that bacteriocin KT11 was antagonistically effective against various Gram-positive and Gram-negative test bacteria, including vancomycin- and/or methicillin-resistant bacteria. The activity of bacteriocin KT11 was completely abolished after treatment with proteolytic enzymes (proteinase K, ${\alpha}$-chymotrypsin, protease and trypsin), which demonstrates the proteinaceous nature of this bacteriocin. Additionally, bacteriocin KT11 remained stable at pH values ranging from 2 to 11 and after autoclaving at $121^{\circ}C$ for 30 min. In addition, the activity of bacteriocin KT11 was stable after treatment with several surfactants (EDTA, SDS, Triton X-100, Tween 80 and urea) and organic solvents (chloroform, propanol, methanol, ethyl alcohol, acetone, hexane and ethyl ether). Cell-free supernatant of E. faecalis KT11 was subjected to ammonium sulfate precipitation and then desalted by using a 3.5-kDa cut-off dialysis membrane. The bacteriocin activity was determined to be 711 AU/mL in the dialysate. After tricine-SDS-PAGE analysis, one peptide band, which had a molecular weight of ~3.5 kDa, exhibited antimicrobial activity. Because the bacteriocin KT11, isolated from E. faecalis KT11, exhibits a broad antimicrobial spectrum, heat stability and stability over a wide pH range, this bacteriocin can be used as a potential bio-preservative in foods. Additionally, bacteriocin KT11 alone or in combination with conventional antibiotics may provide a therapeutic option for the treatment of multidrug-resistant clinical pathogens after further in vivo studies.

• Journal of Yeungnam Medical Science
• /
• v.37 no.2
• /
• pp.112-121
• /
• 2020

Background: Vancomycin-resistant Enterococcus (VRE) has become more common in nosocomial infections, especially in urine samples. However, until now, no treatment regimen has been proven to effectively eradicate urine VRE colonization. Therefore, to evaluate the efficacy of doxycycline in eradicating urine VRE and shortening VRE isolation period, we compared VRE colony detection period between doxycycline-treated and untreated patients. Methods: A retrospective cohort study of 83 patients with VRE colonization in urine cultures was conducted at a tertiary academic hospital from January 2011 to February 2018. Kaplan-Meier survival analysis was used to evaluate eradication rates in the treatment and non-treatment groups. Factors affecting urine VRE colonization persistence were analyzed by multiple logistic regression analysis. Results: The overall rate of VRE eradication during the entire hospital stay was higher in the doxycycline treatment group (90.5%) than in the non-treatment group (58.1%, p=0.014). Survival analysis showed that the 5-, 10-, and 20-day cumulative eradication rates were 78.3%, 100%, and 100% in the doxycycline treatment group, and 18.5%, 45.7%, and 67.8% in the non-treatment group, respectively, thereby indicating that eradication rates were higher in the doxycycline treatment group than in the non-treatment group (p<0.001). Only doxycycline treatment was shown to affect urine VRE colonization persistence in multivariate logistic regression analysis. Conclusion: Doxycycline treatment enhanced the eradication rate of urine VRE colonization and appeared to be useful in shortening VRE isolation period.

• Biomedical Science Letters
• /
• v.19 no.3
• /
• pp.245-253
• /
• 2013

To provide reference data or guideline for empirical treatment of bloodstream infection, we studied a change pattern in causative microorganisms and antimicrobial susceptibility in a general hospital at Gyeonggi province during five years. We retrospectively reviewed the frequency of causative microorganisms and antimicrobial susceptibility results of 5,782 microorganisms isolated from blood culture in a general hospital during the period from January 2008 to December 2012. The most common pathogens were Escherichia coli (14.7%), Staphylococcus aureus (7.5%), Streptococcus viridans group (4.9%), and Klebsiella pneumoniae (4.1%). The multiple microorganisms were isolated in 4.3% of bloodstream infection patients. The average contamination rate of blood culture during five years was 3.0%. Methicillin-resistant S. aureus (MRSA), vancomycin-resistant Enterococcus faecium (VRE), and penicillin-resistant Streptococcus pneumoniae were isolated at 62%, 27% and 11%, respectively. Cefotaxime-resistant E. coli and K. pneumoniae was 20% and 18%, respectively. Imipenem-resistant Pseudomonas aeruginosa (IRPA) and Acinetobacter baumannii (IRAB) was 25% and 66%, respectively. E. coli and S. aureus were most common pathogens isolated from blood culture for five years. The increase of multidrug-resistant microorganisms, such as MRSA, VRE, ESBL, IRPA and IRAB, requires more strict control of antibiotics and causes the need of the more updated guideline for the treatment of blood stream infection.

• Pediatric Infection and Vaccine
• /
• v.12 no.2
• /
• pp.157-165
• /
• 2005

Purpose : Children occupy a large proportion of burn victims. So we want to aid to pediatric burn care through the understanding of the bacterial distribution in burn wounds and antibiotic susceptibility against isolated microorganisms from burn wounds. Methods : We analysed the medical records of 213 pediatric burn patients(0~15 years), 406 samples that grew bacteria in burn wound sites. Results : Of the total 213 patients, male were 59.6% and female were 40.4%. Scalding burn was the most common(78.4%), flame burn was the second(16.4%). Pathogens were isolated in 406 samples. The most common was Pseudomonas aeruginosa(58.1%). Next were Enterococcus species, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus species, Acinetobacter species. P. aeruginosa was resistant to trimethoprim-sulfamethoxazole in 100%, cephalothin in 98.1%, ampicillin-sulbactam in 96.2%, ampicillin in 95.3%, ceftriaxone in 95.2%, tobramycin in 93.7%, cefoperazone in 68.9%, ceftazidime in 67.7%. Enterococcus species were resistant to tetracycline in 63.9%, streptomycin in 45.5%, gentamicin in 36.1%, penicillin G in 13.7%. S. aureus was resistant to gentamicin in 89.7%, tetracycline in 86.2%, ciprofloxacin in 86.2%, penicillin G in 84.3%, oxacillin in 78.4%, erythromycin in 76.5%. Acinetobacter species were resistant to ampicillin-sulbactam in 100%, gentamicin in 85.7%, ampicillin in 83.3%, piperacillin in 61.5%. Conclusion : P. aeruginosa was highly resistant to drugs like cefoperazone in 68.9%, ceftazidime 67.7%. S. aureus was highly resistant to penicillin G in 84.3%, oxacillin in 25.9 %, but none to vancomycin in 0%, teicoplanin in 2.2%. According to the study, Acinetobacter species turned out to be multi-resistant strains, so careful attention must be paid to the choice of antibiotics.

• Journal of Korean Medical Science
• /
• v.33 no.48
• /
• pp.295.1-295.7
• /
• 2018

Background: Vancomycin-resistant enterococci (VRE) infections have become a major healthcare-associated pathogen problem worldwide. Nosocomial VRE infections could be effectively controlled by screening patients at high risk of harboring VRE and thereby lowering the influx of VRE into healthcare centers. In this study, we evaluated factors associated with VRE colonization in patients transferred to emergency departments, to detect patients at risk for VRE carriage. Methods: This study was conducted in the emergency department of a medical college-affiliated hospital in Korea. Every patient transferred to the emergency department and admitted to the hospital from January to December 2016 was screened for VRE using rectal cultures. In this cross-sectional study, the dependent variable was VRE colonization and the independent variables were demographic and clinical factors of the patients and factors related to the transferring hospital. Patients were divided into two groups, VRE and non-VRE, and previously collected patient data were analyzed. Then we performed logistic regression analyses of characteristics that differed significantly between groups. Results: Out of 650 patients, 106 (16.3%) had positive VRE culture results. Significant variables in the logistic analysis were transfer from geriatric long-term care hospital (adjusted odds ration [aOR]: 8.017; 95% confidence interval [CI]: 1.378-46.651), hospital days (4-7 days; aOR: 7.246; 95% CI: 3.229-16.261), duration of antimicrobial exposure (1-3 days; aOR: 1.976; 95% CI: 1.137-3.436), and age (aOR: 1.025; 95% CI: 1.007-1.043). Conclusion: VRE colonization in patients transferred to the emergency department is associated primarily with factors related to the transferred hospitals rather than demographic and clinical characteristics.

• Journal of Pharmacopuncture
• /
• v.26 no.3
• /
• pp.247-256
• /
• 2023

Objectives: Enterococcus faecalis is a gram positive diplococci, highly versatile and a normal commensal of the gut microbiome. Resistance to vancomycin is a serious issue in various health-care setting exhibited by vancomycin resistant Enterococci (VRE) due to the alteration in the peptidoglycan synthesis pathway. This study is thus aimed to detect the VRE from the patients with root caries from the clinical isolates of E. faecalis and to evaluate the in-silico interactions between vanA and the Aegles marmelos bio-compounds. Methods: E. faecalis was phenotypically characterized from 20 root caries samples and the frequency of vanA and vanB genes was detected by polymerase chain reaction (PCR). Further crude methanolic extracts from the dried leaves of A. marmelos was assessed for its antimicrobial activity. This is followed by the selection of five A. marmelos bio-compounds for the computational approach towards the drug ligand interactions. Results: 12 strains (60%) of E. faecalis was identified from the root caries samples and vanA was detected from two strains (16%). Both the stains showed the presence of vanA and none of the strains possessed vanB. Crude extract of A. marmelos showed promising antibacterial activity against the VRE strains. In-silico analysis of the A. marmelos biocompounds revealed Imperatonin as the best compound with high docking energy (-8.11) and hydrogen bonds with < 140 TPSA (Topological polar surface area) and zero violations. Conclusion: The present study records the VRE strains among the root caries with imperatorin from A. marmelos as a promising drug candidate. However the study requires further experimentation and validation.

• Journal of Food Hygiene and Safety
• /
• v.29 no.3
• /
• pp.228-233
• /
• 2014

This study was performed to examine antimicrobial resistance of Enterococcus spp. strains from retail raw meat and fish products purchased in 2012. 43 Enterococcus spp. strains were isolated from a total of 207 samples (beef, pork, chicken, fish) with contamination rate of 20.8%. The isolated strains were identified as E. faecalis (22 strains), E. gallinarum, E. hirae (5 strains), E. avium (4 strains), E. faecium (3 strains), E. duram, E. casseliflavus (2 strains). Susceptibility to 10 antibiotics was tested, and the highest resistance was observed to tetracycline. And antimicrobial resistance rates were presented below 20% with most of the other antimicrobial agents. The isolated Enterococci from chicken showed higher resistance also to ciprofloxacin and erythromycin, not only to tetracycline, compared to the isolated Enterococci from beef, pork and fish. Sixteen isolates (37.2%) were sensitive to all antibiotics. Four isolates (9.3%) were resistant to 3 or more antibiotics. Vancomycin-resistant enterococci (VRE) was not identified. According to the results of genetic similarity pattern analysis via PFGE and rep-PCR, Enterococci strains showed different patterns from these collected in 2011. This indicates that there is no genetic similarity among all the strains.

• The Journal of Internal Korean Medicine
• /
• v.41 no.6
• /
• pp.1191-1199
• /
• 2020

We studied the effect of Korean medicine treatment on the clearance of vancomycin-resistant enterococcus (VRE) colonization and on improvement in symptoms in a stroke patient. The patient was continuously followed up with stool VRE cultures while being treated with herbal medicine, Chunglijagam-tang, acupuncture, and oxygen therapy. We also checked the coccygeal pressure sore condition and the oxygen levels during therapy. No VRE colonization was found after treatment and the oxygen levels and pressure sores had improved. This study proved that Korean medicine treatment could be effective for the clearance of VRE colonization and improvement of symptoms.

• Biomedical Science Letters
• /
• v.21 no.2
• /
• pp.84-91
• /
• 2015

To provide guidelines for the empirical treatment of urinary tract infections, we observed annual changes in the occurrence frequency and antimicrobial susceptibility of urinary isolates in a university hospital in the Chungbuk province, South Korea, over a period of 10 years (2004~2013). Escherichia coli (38.2%), Enterococcus faecalis (11.7%), Klebsiella pneumoniae (7.3%), Pseudomonas aeruginosa (4.3%), E. faecium (4.3%), and Staphylococcus aureus (4.1%) were commonly isolated urinary pathogens. The prevalence of E. coli, E. faecium and Streptococcus agalactiae were significantly higher in females (P < 0.001), whereas E. faecalis, P. aeruginosa and S. aureus were significantly more common in male patients (P < 0.001). E. coli mostly frequently showed resistance to ampicillin (67.94%), followed by trimethoprim/sulfamethoxazole (36.06%) and ciprofloxacin (26.84%). Over the studied time period, resistance rates of E. coli to ciprofloxacin significantly increased (20.44% to 33.55%). Moreover, extended-spectrum $\beta$-lactamase (ESBL) producing isolates also significantly increased in E. coli (4.2% to 18.3%) and K. pneumoniae (9.6% to 26.9%). In addition, the proportion of vancomycin-resistant Enterococcus facium (VRE) also increased (15.7% to 25.0%). In conclusion, over the last 10 years, the proportions of ciprofloxacin resistant E. coli and multidrug-resistant bacteria, such as ESBL and VRE have significantly increased. This trend must be strictly controlled and demonstrates the need for more updated guidelines for the treatment of urinary tract infections.

• The Korean journal of internal medicine
• /
• v.39 no.3
• /
• pp.448-457
• /
• 2024

Background/Aims: Improved knowledge of local epidemiology and predicting risk factors of multidrug-resistant (MDR) bacteria are required to optimize the management of infections. This study examined local epidemiology and antibiotic resistance patterns of liver cirrhosis (LC) patients and evaluated the predictors of MDR bacteremia in Korea. Methods: This was a retrospective study including 140 LC patients diagnosed with bacteremia between January 2017 and December 2022. Local epidemiology and antibiotic resistance patterns and the determinants of MDR bacteremia were analyzed using logistic regression analysis. Results: The most frequently isolated bacteria, from the bloodstream, were Escherichia coli (n = 45, 31.7%) and Klebsiella spp. (n = 35, 24.6%). Thirty-four isolates (23.9%) were MDR, and extended-spectrum beta-lactamase E. coli (52.9%) and methicillin-resistant Staphylococcus aureus (17.6%) were the most commonly isolated MDR bacteria. When Enterococcus spp. were cultured, the majority were MDR (MDR 83.3% vs. 16.7%, p = 0.003), particularly vancomycin-susceptible Enterococcus faecium. Antibiotics administration within 30 days and/or nosocomial infection was a significant predictor of MDR bacteremia (OR: 3.40, 95% CI: 1.24-9.27, p = 0.02). MDR bacteremia was not predicted by sepsis predictors, such as positive systemic inflammatory response syndrome (SIRS) or quick Sequential Organ Failure Assessment (qSOFA). Conclusions: More than 70% of strains that can be treated with a third-generation cephalosporin have been cultured. In cirrhotic patients, antibiotic administration within 30 days and/or nosocomial infection are predictors of MDR bacteremia; therefore, empirical administration of broad-spectrum antibiotics should be considered when these risk factors are present.