BACKGROUND: Antimicrobial resistance (AMR) is an issue not only with regard to public health, but also in terms of economic impact. AMR surveillance has mainly been carried out in general hospitals, and not in nursing hospitals. This study was conducted to investigate the AMR rate for bacterial strains isolated from nursing hospital samples.METHODS: Antimicrobial susceptibility testing (AST) results from a total of 23,518 bacterial isolates recovered from clinical specimens taken in 61 nursing hosals were analyzed. AST was conducted using Vitek 2 with AST cards specific for the bacterial strains.RESULTS: A total of 19,357 Gram-negative and 4,161 Gram-positive bacterial strains were isolated. Pseudomonas aeruginosa (n=6,384) and Escherichia coli (n=5,468) were the most prevalent bacterial species and, among Gram-positive bacteria, Staphylococcus aureus (n=1,565) was common. The AMR rate was high for the following strains: cefotaxime-resistant Klebsiella pneumoniae, 77.4%; cefotaxime-resistant E. coli, 70.6%; imipenem-resistant Acinetobacter baumannii, 90.3%; imipenem-resistant P. aeruginosa, 49.3%; oxacillin-resistant S. aureus, 81.1%, penicillin-resistant Enterococcus faecalis, 44.8%, and vancomycin-resistant Enterococcus faecium, 53.5%. AMR rate change varied by bacterial species and antimicrobial drug.CONCLUSION: AMR rates of major pathogens from nursing hospitals were higher than those from general hospitals with the exception of imipenem-resistant A. baumannii. Continuous monitoring and infection control strategies are needed.
Acinetobacter baumannii ; Enterococcus faecalis ; Enterococcus faecium ; Escherichia coli ; Gram-Positive Bacteria ; Hospitals, General ; Infection Control ; Klebsiella pneumoniae ; Nursing ; Pseudomonas aeruginosa ; Public Health ; Staphylococcus aureus

By activity-guided fractionation, gliotoxin was isolated as an antibacterial metabolite of the fungus Penicillium decumbens which was derived from the jellyfish Nemopilema nomurai. Gliotoxin was further evaluated for antibacterial activity against several piscine and human MDR (multidrug resistance) pathogens. Gliotoxin showed significant antibacterial activity against Gram-positive piscine pathogens such as Streptococcus iniae FP5228, Streptococcus iniae FP3187, Streptococcus parauberis FP3287, Streptococcus parauberis SPOF3K, S. parauberis KSP28, and Lactococcus garvieae FP5245. Gliotoxin showed strong activity especially against S. parauberis SPOF3K and S. iniae FP5228, which are resistant to oxytetracycline. It is noteworthy that gliotoxin effectively suppressed streptococci which are the major pathogens for piscine infection and mortality in aquaculture industry. Gliotoxin also showed strong antibacterial activity against multidrug-resistant human pathogens (MDR) including Enterococcus faecium 5270 and MRSA (methicillin-resistant Staphylococcus aureus) 3089.
Aquaculture ; Enterococcus faecium ; Fungi ; Gliotoxin ; Humans ; Lactococcus ; Methicillin-Resistant Staphylococcus aureus ; Mortality ; Oxytetracycline ; Penicillium ; Staphylococcus ; Streptococcus

BACKGROUND: Enterococcus faecium, especially vancomycin-resistant E. faecium (VREfm), is a major concern for patients with hematologic diseases. Exposure to antibiotics including fluoroquinolone, which is used as a routine prophylaxis for patients with hematologic (MH) diseases, has been reported to be a risk factor for infection with vancomycin-resistant eneterocci. We compared the characteristics of E. faecium isolates according to their vancomycin susceptibility and patient group (MH vs non-MH patients). METHODS: A total of 120 E. faecium bacteremic isolates (84 from MH and 36 from non-MH patients) were collected consecutively, and their characteristics (susceptibility, multilocus sequence type [MLST], Tn1546 type, and the presence of virulence genes and plasmids) were determined. RESULTS: Among the vancomycin-susceptible E. faecium (VSEfm) isolates, resistance to ampicillin (97.6% vs 61.1%) and high-level gentamicin (71.4% vs 38.9%) was significantly higher in isolates from MH patients than in those from non-MH patients. Notably, hyl, esp, and pEF1071 were present only in isolates with ampicillin resistance. Among the VREfm isolates, ST230 (33.3%) and ST17 (26.2%) were predominant in MH patients, while ST17 (61.1%) was predominant in non-MH patients. Plasmid pLG1 was more prevalent in E. faecium isolates from MH patients than in those from non-MH patients, regardless of vancomycin resistance. Transposon analysis revealed five types across all VREfm isolates. CONCLUSIONS: The antimicrobial resistance profiles and molecular characteristics of E. faecium isolates differed according to the underlying diseases of patients within the same hospital. We hypothesize that the prophylactic use of fluoroquinolone might have an effect on these differences.
Ampicillin ; Ampicillin Resistance ; Anti-Bacterial Agents ; Enterococcus faecium* ; Enterococcus* ; Gentamicins ; Hematologic Diseases ; Humans ; Multilocus Sequence Typing ; Plasmids ; Risk Factors ; Vancomycin ; Vancomycin Resistance ; Virulence

OBJECTIVETo summarize the clinical features of Enterococcus faecium meningitis in children.

METHODSThe clinical data of nine children with Enterococcus faecium meningitis were analyzed.

RESULTSIn all the nine children, Enterococcus faecium was isolated from blood, cerebrospinal fluid, or peripherally inserted central catheters; 6 (67%) patients were neonates, 2 (22%) patients were younger than 6 months, and 1 (11%) patient was three years and four months of age. In those patients, 56% had high-risk factors before onset, which included intestinal infection, resettlement of drainage tube after surgery for hydrocephalus, skull fracture, perinatal maternal infection history, and catheter-related infection. The main symptoms were fever and poor response. In those patients, 22% had seizures; no child had meningeal irritation sign or disturbance of consciousness. The white blood cell count and level of C-reactive protein were normal or increased; the nucleated cell count in cerebrospinal fluid was normal or mildly elevated; the protein level was substantially elevated; the glucose level was decreased. The drug sensitivity test showed that bacteria were all sensitive to vancomycin and the vancomycin treatment was effective. Only one child had the complication of hydrocephalus.

CONCLUSIONSEnterococcus faecium meningitis occurs mainly in neonates and infants. The patients have atypical clinical features. A high proportion of patients with Enterococcus faecium meningitis have high-risk factors. Enterococcus faecium is sensitive to vancomycin.

C-Reactive Protein ; analysis ; Enterococcus faecium ; drug effects ; Female ; Gram-Positive Bacterial Infections ; blood ; diagnosis ; drug therapy ; etiology ; Humans ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial ; blood ; diagnosis ; drug therapy ; etiology ; Vancomycin ; pharmacology

BACKGROUND: The aim of this study was to comparatively evaluate the bactericidal effects of copper, brass (copper 78%, tin 22%), and stainless steel against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecium (VREFM), and multidrug-resistant Pseudomonas aeruginosa (MRPA). METHODS: The isolates (MRSA, VREFM, MRPA) used in this study were mixed wild type 3 strains isolated from patients treated at Uijeongbu St. Mary's Hospital in 2017. These strains showed patterns of multidrug resistance. The lyophilized strains were inoculated into and incubated for 24 hr in tryptic soy broth at 35℃. The initial bacterial inoculum concentration was adjusted to 105 CFU/mL. A 100-mL bacterial suspension was incubated in containers made of brass (copper 78%, tin 22%), copper (above 99% purity), and stainless steel at 35℃. Viable counts of bacteria strains were measured for 9 days. RESULTS: In this study, the bactericidal effects of copper and brass on MRSA, VREFM, and MRPA were verified. The bactericidal effect of stainless steel was much weaker than those of copper and brass. The bactericidal effect was stronger on MRPA than on MRSA or VREFM. CONCLUSION: To prevent cross infection of multidrug resistant bacteria in hospitals, further studies of longer duration are needed for testing of copper materials on objects such as door knobs, faucets, and bed rails.
Bacteria ; Copper ; Cross Infection ; Drug Resistance, Multiple ; Enterococcus faecium ; Humans ; Methicillin-Resistant Staphylococcus aureus ; Pseudomonas aeruginosa ; Stainless Steel ; Tin

BACKGROUND: Meningitis is a clinically important disease because of its high mortality and morbidity. The epidemiology of this disease has changed remarkably due to the introduction of pneumococcal vaccines and Haemophilus influenzae type b (Hib) conjugate vaccine. Therefore, it is required to continuously monitor and research the organisms isolated from cerebrospinal fluid (CSF) cultures. METHODS: We analyzed trends of bacteria and fungi isolates obtained from CSF cultures between 1997 and 2016 in a tertiary care hospital according to year, month, gender, and age. RESULTS: Out of a total of 38,450 samples, we identified 504 (1.3%) isolates. The isolation rate in the first tested decade (1997–2006) ranged from 1.3% to 3.1%, while that in the second decade (2007–2016) ranged from 0.4% to 1.5%. The most common organisms was coagulase-negative staphylococci (CoNS) (31.9%), followed by Staphylococcus aureus (9.5%), Streptococcus pneumoniae (7.5%), Acinetobacter baumannii (5.8%), and Mycobacterium tuberculosis (5.8%). Monthly isolation rates were highest in May and July and lowest in February and December. Male to female ratio was 1.5:1. The isolation rates of S. pneumoniae, Enterococcus faecium, and Escherichia coli were similar in children and adults, but those of S. aureus, E. faecalis, A. baumannii, Pseudomonas aeruginosa, M. tuberculosis, and Cryptococcus neoformans were higher in adults than in children. CONCLUSION: During the last two decades, the isolation rate of CSF culture per year has decreased, with monthly isolation rates being highest in May and July. CoNS, S. aureus, and S. pneumoniae were most common in males, whereas CoNS, S. pneumoniae, and M. tuberculosis were most common in females. While Group B Streptococcus was most common in infants younger than 1 year, S. aureus and C. neoformans were more common in adults.
Acinetobacter baumannii ; Adult ; Bacteria* ; Cerebrospinal Fluid* ; Child ; Cryptococcus neoformans ; Enterococcus faecium ; Epidemiology ; Escherichia coli ; Female ; Fungi* ; Haemophilus influenzae type b ; Humans ; Infant ; Male ; Meningitis ; Mortality ; Mycobacterium tuberculosis ; Pneumococcal Vaccines ; Pneumonia ; Pseudomonas aeruginosa ; Staphylococcus aureus ; Streptococcus ; Streptococcus pneumoniae ; Tertiary Healthcare* ; Tuberculosis

BACKGROUND: Multilocus sequence typing (MLST) is useful in determining the long-term evolutionary process and minimizes differences in experimental results across individuals and laboratories. It is also useful in determining evolutionary origins and backgrounds of bacterial species. This study carries out MLST analysis on VanA-type vancomycin-resistant Enterococcus faecium isolated from patient specimens in a single university hospital over nine years in order to observe changes in genetic evolution over time. METHODS: During the years from 2007 to 2015, 44 clinical isolates of vanA-containing E. faecium were collected from Ajou University Hospital in Korea. Species were identified by the VitekII system (bio-Merieux, USA), and antibiotic susceptibility testing was performed by disk diffusion and E-test according to Clinical and Laboratory Standards Institute (CLSI) guidelines. To determine genetic relatedness, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF M/S) was employed. To characterize clonal diversity, MLST analysis was used. RESULTS: All isolates were highly resistant to ampicillin, ciprofloxacin, and vancomycin but showed variable levels of resistance to teicoplanin. The 44 clinical isolates were genetically unrelated according to MALDI-TOF M/S analysis. MLST showed that the clinical isolates harbored 6 sequence types (ST), with ST17 (n=19) being the most common, followed by ST78 (n=13), ST192 (n=6), ST64 (n=4), ST262 (n=1), and ST414 (n=1). CONCLUSION: The MLST analysis showed that the sequence types of most isolates belonged to clonal complex 17 This is consistent with outbreaks in hospitals. We had single observations for ST262 and ST414, suggesting that they were random occurrences. MLST can be useful for speculating the genetic evolution of VanA-containing E. faecium isolates.
Ampicillin ; Ciprofloxacin ; Diffusion ; Disease Outbreaks ; Enterococcus faecium* ; Enterococcus* ; Evolution, Molecular ; Humans ; Korea ; Mass Spectrometry ; Multilocus Sequence Typing* ; Teicoplanin ; Vancomycin

The study was conducted to investigate the distribution of pathogenic bacteria related to agricultural herb products that are sold on the market in South Korea. A survey was conducted on the microbial contamination levels and antibiotic susceptibility of Bacillus cereus (B. cereus) among 194 agricultural herb products on sale in Seoul. Distributions of those isolates were 252 coliforms, 148 Bacillus spp., 75 Enterococcus spp., 10 Staphylococcus spp., and 6 Listeria spp., respectively. The number of B. cereus isolates was 34, Escherichia coli isolates was three, Enterococcus faecium isolate was one, and Enterococcus faecalis isolate was one. Antibiotic susceptibility of B. cereus isolates was tested against 36 kinds of antibiotic susceptibility discs by disc diffusion method. B. cereus isolates were resistant to 20 kinds of antibiotics and semi-resistant to 11 kinds of antibiotics. On the basis of these results, any agricultural herb product can be assumed to be resistant or semi-resistant to the antibiotics used in human. In conclusion, we suggest sanitary control and special management regarding B. cereus contamination in agricultural herb products.
Anti-Bacterial Agents ; Bacillus cereus ; Bacillus* ; Bacteria ; Commerce ; Diffusion ; Enterococcus faecalis ; Enterococcus faecium ; Enterococcus* ; Escherichia coli ; Humans ; Korea ; Listeria* ; Methods ; Seoul ; Staphylococcus*

BACKGROUND: National surveillance of antimicrobial resistance becomes more important for the control of antimicrobial resistance and determination of treatment guidelines. We analyzed Korean Antimicrobial Resistance Monitoring System (KARMS) data collected from 2013 to 2015. METHODS: Of the KARMS participants, 16 secondary or tertiary hospitals consecutively reported antimicrobial resistance rates from 2013 to 2015. Data from duplicate isolates and institutions with fewer than 20 isolates were excluded. To determine the long-term trends, previous KARMS data from 2004 to 2012 were also considered. RESULTS: The prevalence of methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium from 2013 to 2015 was 66–72% and 29–31%, respectively. The resistance rates of Escherichia coli to cefotaxime and cefepime gradually increased to 35% and 31%, respectively, and fluoroquinolone resistance reached 48% in 2015. The resistance rates of Klebsiella pneumoniae to cefotaxime, cefepime, and carbapenem were 38–41%, 33–41%, and <0.1–2%, respectively, from 2013 to 2015. The carbapenem susceptibility rates of E. coli and K. pneumoniae decreased from 100% and 99.3% in 2011 to 99.0% and 97.0% in 2015, respectively. The resistance rate of Pseudomonas aeruginosa to carbapenem increased to 35% and the prevalence of carbapenem-resistant Acinetobacter baumannii increased from 77% in 2013 to 85% in 2015. CONCLUSIONS: Between 2013 and 2015, the resistance rates of E. coli to third- and fourth-generation cephalosporins increased continuously, while carbapenem-susceptibility gradually decreased, particularly in K. pneumoniae. The prevalence of carbapenem-resistant P. aeruginosa and A. baumannii increased significantly; therefore, few treatment options remain for these resistant strains.
Acinetobacter baumannii ; Cefotaxime ; Cephalosporins* ; Drug Resistance, Microbial ; Enterococcus faecium ; Escherichia coli ; Klebsiella pneumoniae* ; Klebsiella* ; Methicillin-Resistant Staphylococcus aureus ; Pneumonia ; Prevalence ; Pseudomonas aeruginosa ; Tertiary Care Centers

Blood culture is important to detecting bacteremia and fungemia in patients with suspected sepsis. We observed a four-year trend of blood culture isolates in the frequency by age group and in vitro antimicrobial susceptibility patterns obtained at VHS Medical Center, the largest veterans hospital in Korea. Blood cultures collected between 2012 and 2015 were analysed retrospectively. Of 68,352 blood specimens, 7,901 isolates were identified during the study period. Seventy-two percent of the isolates were gram-positive cocci, 18% were gram-negative rods, and 6% were fungi. The frequency of bacteremia/fungemia in patients who were 80–89 years old was 43.8%, the highest rate among all age groups, and the mean age of patients diagnosed by blood culture was 77 years old. Coagulase-negative staphylococcus (52.3%), Staphylococcus aureus (8.3%), enterococci (7.5%), Escherichia coli (6.4%), and Klebsiella pneumoniae (3.9%) were the bacteria most commonly isolated. The percentage of methicillin-resistant S . aureus increased in 2015 (76%) relative to that in 2012–2014 (63%–65%), and that of vancomycin-resistant Enterococcus faecium was 17%–22% with no significant changes through time. Among the gram-negative isolates, the ciprofloxacin resistance rate increased to 51.4% (E. coli ) and 31.1% (K. pneumoniae ) in 2015, but imipenem or ertapenem resistance was still very rare, with resistance rates of less than 0.5%. Acinetobacter baumannii showed a high rate of resistance (over 70%) to imipenem and ciprofloxacin throughout the study. In Pseudomonas aeruginosa , the resistance rates of imipenem and ciprofloxacin increased dramatically over time. This analysis confirmed a decrease in antimicrobial susceptibility of gram-negative rods isolated by blood culture.
Acinetobacter baumannii ; Bacteremia ; Bacteria ; Ciprofloxacin ; Enterococcus faecium ; Escherichia coli ; Fungemia ; Fungi ; Gram-Positive Cocci ; Hospitals, Veterans* ; Humans ; Imipenem ; In Vitro Techniques ; Klebsiella pneumoniae ; Korea ; Methicillin Resistance ; Pneumonia ; Pseudomonas aeruginosa ; Retrospective Studies ; Sepsis ; Staphylococcus ; Staphylococcus aureus ; Veterans*