• Journal of Microbiology
• /
• 제40권2호
• /
• pp.170-172
• /
• 2002

To determine the occurrence of vancomycin-resistant Enterococci in a raw milk sample, raw milk samples were examined for a period of 6 months. Enterococci were isolated directly from Enterococcal selective agar plates supplemented with 2 mg of vancomycin per liter, Nineteen strains were selected and identified by applying the Vitek system. To determine resistance patterns, 19 isolates were tested with vancomycin and teicoplanin. Vancomycin-resistant Enterococci were genotyped by using a PCR analysis and 5 out of 19 isolates were of the VanC type.

• 대한의생명과학회지
• /
• 제5권1호
• /
• pp.95-100
• /
• 1999

일반적으로 임상검사실에서 vancomycin resistant enterococci (VRE)를 검출하는 일은 어렵고, 시간이 많이 들며, 검체처리 비용도 많이 든다. 따라서 본 실험은 임상검체에서 분리된 세균으로부터 VRE를 신속하게 확인하고, 진단하기 위한 방법으로서 다중 중합효소 연쇄반응을 확립하였다. 본 실험에 사용된 primer는 장구균에 특이 한 유전자인 vanA, vanB, vanC-1, vanC-2/3 각각의 염기서열을 기초로 primer를 제작하고, 다중 중합효소 연쇄 반응을 실시하여 임상검체로부터 분리된 VRE 유전자의 type및 분포율을 조사하고자 하였다. 국내에서 분리된 75주의 장구균을 대상으로 다중 중합효소 연쇄반응을 실시한 결과 36주의 분리균주에서 vancomycin에 대해 높은 저항성을 보이는 vanA 유전자를 가진 것으로 나타났다. 그리고 18주에서는 vancomycin에 낮은 저항성을 내성을 보이는 vanC-1 또는 vanC-2/3 유전자를 보유한 것으로 나타났다. 따라서 본 실험에서 확립한 다중 중합효소 연쇄 반응 기법은 신속한 VRE 진단 방법으로 이용할 수 있을 것이다.

• 대한임상검사과학회지
• /
• 제45권1호
• /
• pp.16-20
• /
• 2013

Outbreaks of vancomycin-resistant enterococci (VRE) are being reported more frequently in many countries. While seven glycopeptide resistance genotypes have been described in Enterococci, vanA and vanB are the most common resistance genotypes. The aim of this study was to detect antibiotic susceptibilities of 23 Enterococcus faecium strains, which caused an outbreak in a University hospital by a disk diffusion test to investigate the presence of the species specific gene, and the resistant genotypes, vanA and vanB by duplex PCR. PCR for vanA and vanB was performed on 23 enterococci. Twenty three were identified as E. faecium and were tested positive for the vanA genotype. This study will report on the validation of a simple and accurate VRE detection method that can be easily incorporated into the daily routine of a clinical laboratory. Early detection of VRE strains, including those with susceptibility to vancomycin, is of paramount clinical importance as it allows rapid initiation of strict infection control practices, as well as the therapeutic guidance for confirmed infections. The PCR method developed in the present study is simple and reliable for the rapid characterization of VRE.

• Journal of Microbiology
• /
• 제39권2호
• /
• pp.116-120
• /
• 2001

The prevalence resistance genotype and antibiotic susceptibility of vancomycin-resistant enterococci (VRE) were determined. Prevalence of VRE in chickens, healthy children and intensive care unit (ICU) patients was 43.0%, 12.7% and 24.1%, respectively. Forty out of 56 isolates from chicken intestines were identified as Enterococcus faecium, and 12 were E. faecalis. All the isolates contained the vanA gene. Nine out of 13 VRE isolates from patients and two out of 21 from healthy young children were identified as E. faecium. The resistance types of E. faecium, E. gallinarium and E. casseliflavus were VanA, VanCl, and VanC2, respectively. The minimum inhibitory concentrations (MICs) of E. faecium, E. gallinarium, and E. casseliflavus to vancomycin were 512,8 and 4 g/ml, respectively. Specifically, E. faecium isolates were resistant to most of antibiotics except ampicillin and gentamicin. This is the first report of high VanA type VRE prevalence in nonhospitalized young children in Korea.

• 대한의생명과학회지
• /
• 제26권3호
• /
• pp.149-156
• /
• 2020

We developed a simple and rapid method for detecting vancomycin resistance genes, such as vanA and vanB, using loop-mediated isothermal amplification (LAMP). To identify not only vancomycin resistance genes, but also the genus Enterococcus, primers were designed for vanA, vanB, and 16S rRNA. Screening for vancomycin susceptibility in Enterococcus was performed using Etest (bioMérieux Inc). The results of the LAMP assay were compared to those of real-time RT-PCR. The optimal conditions for the LAMP assay were 65℃ for 60 min. The detection limits of the LAMP assay for vanA, and vanB were 2 × 10² copies/reaction. Compared to RT-PCR, the sensitivities and specificities of LAMP for 16S rRNA, vanA, and vanB were 100/100%, 100/100%, and 100/100%, respectively. The vanA genotype-vanB phenotype accounted for 57.5% (46/80) of the vancomycin-resistant Enterococci samples collected from 2016 to 2019. In conclusion, the LAMP assay developed in this study showed high sensitivity and specificity for vancomycin-resistant genes. Moreover, due to the simplicity and rapidity of the LAMP assay, its use can be very useful in clinical microbiology laboratories.

• 대한임상검사과학회지
• /
• 제43권3호
• /
• pp.124-132
• /
• 2011

The aim of this study was to evaluate the effects of the photosensitizer photogem with light-emitting diode (LED) on vancomycin-resistant enterococci (VRE). Two VRE strains isolated from the feces of patients. that was identificated Enterococcus faecium (vanA) and Enterococcus gallinarum (vanC1) using traditional biochemical tests and confirmed VRE genotyping from using polymerase chain reaction. In addition, three strains were used Enterococcus. faecalis CDC-286 (vanA), E. faecalis CDC-583 (vanB) and E. gallinarum CDC-42 (vanC1). To examine the antimicrobial effect of photogem mediated photodynamic therapy (PDT) against, CFU quantification and Disk diffusion antimicrobial susceptibility test were evaluated. The effects of Photodynamic therapy was not associated with genotype. Photogem mediated PDT perfectly inhibited the colony formation of E. faecalis CDC-286. The number of viable bacteria decreased greatly after PDT application with photogem $50{\mu}g/mL$ and energy density of $15J/cm^2$. The diameter of inhibition zone was increased to after PDT more than before PDT. The case of vancomycin disc on E. faecalis CDC-583 and E. galinanum-Patient were changed from resistant to intermediate resistant, from intermediate resistant to susceptable. These results demonstrate that lethal photosensitization of VRE can be achieved using photogem plus 630 nm LED irradiation.

• 대한수의학회지
• /
• 제39권2호
• /
• pp.343-352
• /
• 1999

Vancomycin resistant enterococci (VRE) have emerged as an important nosocomial pathogen. Since 1989 the Center for Disease Control, United States, has reported a rapid increase in the incidence of enterococcal bacteremia and endocarditis infection by VRE. It was suggested that the use of avoparcin was associated with the appearance of VRE in animal husbandry. To date, several detection methods have been used based on conventional methods of culture and gene detection. However, these methods have some limitations such as time-consuming, laborious and additional differential needs. Therefore, In this study a multiplex PCR method was established to detect and differentiate resistance types of enterococci which specifically amplify the four van genes encoding vancomycin resistance elements. Using the method, we investigated the incidence rates and types of VRE from farms using or not using avoparcin. A total of 1091 animal fecal samples were collected from 70 pig and 32 poultry farms. A total of 425 of enterococci were isolated from samples. Of the 425 isolates, 11 of the them showed a pattern of high-level vancomycin resistance (MIC : $64{\sim}256{\mu}g/ml$) which was associated with the presence of the vanA or vanB gene. Fifty-seven isolates showed a pattern of low-level vancomycin resistance (MIC : $3{\sim}8{\mu}g/ml$) associated with the vanC-1 or vanC-2 gene. Interestingly, all isolates with high-level vancomycin resistance were from farms that have never used avoparcin. Moreover, the high-level VRE isolation rate in Korea (2.58%) was much lower than that of other countries (50% in England, 7% in Belgium) where avoparcin have been used. In conclusion, the multiplex PCR method established in this study could be applied for detection of VRE.

• 대한임상검사과학회지
• /
• 제45권1호
• /
• pp.1-4
• /
• 2013

Vancomycin-resistant enterococci (VRE) have emerged as important healthcare-associated infection since last two decades. ChromID VRE agar (cIDVA) is useful for VRE rectal swab screening. We investigated all VRE were isolated on the cIDVA. A total of 363 rectal swabs of 85 patients to test VRE screening were inoculated into bile-esculin (B-E) broth with $6{\mu}g/mL$ vancomycin. After 24 hours incubation, we subcultured B-E broths were changed to black onto cIDVA. All isolates were identified by the MICROSCAN and VITEK2. The vanA gene and vancomycin minimal inhibition concentration (MIC) were detected by PCR and E-test respectively. 277 E. faecium (84.7%), 16 E. faecalis (4.9%), 25 E. avium (7.6%), 8 E. gallinarum (2.4%) and 1 E. raffinosus (0.3%) were isolated. 10.3% of VRE detected on cIDVA were other than E. faecium and E. faecalis that presented various color from colorless to pale violet. All isolates contained vanA and vancomycin MIC were > $256{\mu}g/mL$. VRE isolates other than E. faecium and E. faecalis should be objective to the contact precautions for healthcare-associated infection control if they possess vanA gene. Due to emerging enterococci carrying vanA such as E. avium, E. gallinarum, and E. raffinosus, VRE surveillance should be expanded to all isolates on chromogenic agar.

• Pediatric Infection and Vaccine
• /
• 제29권2호
• /
• pp.105-109
• /
• 2022

다제내성 반코마이신 저항성 장내구균(multidrug-resistant vancomycin-resistant enterococci, VRE)에 의한 침습감염의 치료는 특히 기저질환을 가진 소아 환자들에게 어려운 점이 있다. 소아환자들에게서 VRE 감염을 치료하기 위한 새로운 항생제에 대한 연구가 충분히 이루어지지 않았다. 본 증례는 심폐이식을 받은 생후 6개월 된 영아에서 linezolid 중단 이후 재발된 VRE 균혈증에 대해 daptomycin과 tigecycline 조합으로 성공적으로 치료하여 이를 보고하는 바이다.

• 대한임상검사과학회지
• /
• 제46권2호
• /
• pp.64-67
• /
• 2014

Vancomycin-resistant Enterococci (VRE) are a leading cause of a nosocomial infection. While seven glycopeptide resistance genotypes have been found in Enterococci, vanA and vanB are the most common resistance genotypes. Aims of this study were to detect antibiotic susceptibilities of 23 Enterococcus spp, which broke out in a university hospital by the disk diffusion test, to investigate specific genes of vanA and vanB by conventional and real-time PCR. PCR for vanA and vanB was performed on 23 Enterococci, all 23 were positive for vanA type. This study reports the validation of a simple and rapid VRE detection method that can be easily incorporated into the daily routine of a clinical laboratory. Early detection of VRE strains, including those with susceptibility to Vancomycin, is of paramount clinical importance, as it allows a rapid initiation of strict infection control practices as well as a therapeutic guidance for a confirmed infection. The real-time PCR method is a rapid technique to detect vanA in Enterococci. It is simple and reliable for the rapid characterization of VRE.