• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.637-642
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• 2010

We investigated the prevalence and the molecular characteristics of vancomycin-intermediate Staphylococcus aureus (VISA) among methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from clinical samples at tertiary or general hospitals participating in a nationwide surveillance program for VISA and vancomycin-resistant Staphylococcus aureus (VRSA) in Korea during an 8-week period in each year from 2001 to 2006. Of 41,639 MRSAs isolated, 37,856 were screened and 169 grew on brain heart infusion agar supplemented with 4 ${\mu}g/ml$ vancomycin. A vancomycin MIC of 4 ${\mu}g/ml$ was confirmed for 33 VISA isolates of the 169 isolates. Eighteen of the 33 isolates were classified as hetero-VISA (hVISA) by the population analysis profile (PAP) method. All VISA isolates were susceptible to linezolid, tigecycline, and quinupristin-dalfopristin. Most VISA isolates (MIC 4 ${\mu}g/ml$) showed a PFGE C pattern with sec, seg, and sei enterotoxin genes, including ST5-SCCmec type II, or a PFGE A pattern with sea, including ST239-SCCmec type III.

• Biomedical Science Letters
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• v.5 no.1
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• pp.131-133
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• 1999

In order to the investigate epidemiological characteristics of methicillin-resistant Staphylococcus aureus (MRSA), 31 strains of Staphylococcus aureus were isolated from the equipments of two hospitals in Chonbuk. And their antimicrobial resistance patterns against 7 kinds of antimicrobial agents and the identification of MRSA by polymerase chain reaction (PCR) were studied. Seven strains among 10 strains of methicillin resistant Staphylococcus aureus showed 554 bp DNA which was a part of mecA gene in PCR analysis.

• YAKHAK HOEJI
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• v.51 no.3
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• pp.164-168
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• 2007

Antibiotic resistance patterns of 21 antibiotics were studied for 50 strains of Staphylococcus aureus isolated from a hospital in Busan from July 2005 to December 2006. All strains showed antibiotic resistance to more than one antibiotic and 3 strains showed resistance to 17 different antibiotics. The strains isolated between 2005 and 2006 had lower resistance rate to 12 antibiotics (other than vancomycin and ampicilin) than the strains isolated between 1989 and 1990. In particular, no chlorarmphenicol resistant strain was found in this study which is contrasted with 34.8% resistant rate obtained in the study conducted between 1989 and 1990. In respect of vancomycin, no resistant strain was found in this study which is the same result obtained in the 1989 to 1990 study; All strains investigated in this study showed 100% resistance rate to ampicillin compared to 69.6% in the previous study.

• The Korean Journal of Health Service Management
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• v.8 no.4
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• pp.163-173
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• 2014

This study was performed to investigate the current status of isolation precautions of multidrug resistant organisms(MDROs) in general hospitals with more than 200bed. The questionnaires were mailed from 3rd, April 2013 to 30th, April 2013. Methicillin resistant Staphylococcus aureus:(MRSA), vancomycin resistant Staphylococcus aureus:(VRSA), vancomycin resistant Enterococcus(VRE), multidrug-resistant Acinetobacter baumannii, carbapenem-resistant Enterobacteriaceae multidrug-resistant Pseudomonas aeruginosa were enrolled. MRSA(100.0%) and VRE(98.7%) were isolated respectively. VRE(97.3%) and MRSA(64.0%) were regulated strictly respectively. VRE(91.5%) and VRSA(50.7%) were isolated in a single room respectively. Hospital being located in Seoul(p<0.001), and beds(${\geq}600$)(p=0.008) were different significantly. The isolation space limitation(71.1%) was the highest difficulty. The development of refunding the costs of the extra supplies and other hygienic materials for infection control was discovered as the most urgent strategy.

• Journal of Microbiology and Biotechnology
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• v.19 no.7
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• pp.734-741
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• 2009

Recently, strains of methicillin-resistant Staphylococcus aureus (MRSA) with reduced susceptibility to vancomycin (VCM) have been clinically isolated. The antibacterial activity of a new drug, linezolid (LZD), in such a strain was evaluated by measuring bacterial metabolic activity. A total of 73 MRSA strains having various susceptibilities to VCM were subjected to a novel and highly sensitive chemiluminescence-based assay. LZD MIC in the tested strains, measured by the microbroth dilution method, was within the range 1-4 mg/l (mostly ${\leq}2$mg/l), except for one LZD-resistant strain (NRS127; MIC=7 mg/l), and showed no correlation with VCM resistance. The chemiluminescence assay demonstrated that bacterial metabolic activity was strongly suppressed with increasing LZD concentration. The chemiluminescence intensity curve had a low baseline activity without tailing in most strains. The present results suggest that LZD has strong antibacterial activity against MRSA strains, and would be effective for treatment of infections that are poorly responsive to VCM. The chemiluminescence assay facilitated sensitive and discriminative susceptibility testing within a relatively short time.

• YAKHAK HOEJI
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• v.50 no.2
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• pp.78-83
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• 2006

VISA and VRE are the main causes of surgical infection, urinary tract infections and bacteremia in hospitals. In this study; we selected VISA (Vancomycin Intermediate resistant Staphylococcus aureus) and VRE (Vancomycin Resistant Enterococcus) isolated from the clinical isolates. One of the isolated strains indicated the high resistance to severel anti-biotics (Vancomycin, Teicoplanin, Mupirocin, Synercid, Ciprofloxacin, Gentamicin, Lincomycin, Cefotaxim, Meropenem). Antimicrobial activity of Bifidobacterium spp. against VISA and VRE were measured. About $10^4$ cells of VISA or VRE were mixed with 1,5 and 9 ml of Bifidobacterium and the final volume was adjusted to 10 ml with brain heart infusion (BHI) broth. The cell suspension was incubated for 3, 6, 9, and 24 hr, serially diluted and then plated on BHI agar plate. As numbers of Bifidobacterium were increased viable cell count of VISA and VRE decreased. The strongest antimicrobial activity of the Bifidobacterium was observed after 9hr incubation in any mixture, almost completely inhibiting the growth of VISA and VRE.

• Pediatric Infection and Vaccine
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• v.16 no.1
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• pp.1-5
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• 2009

Methicillin-resistant Staphylococcus aureus (MRSA), a leading cause of nosocomial infections, has been increasingly recognized in communities of the United States. This article will review the clinical spectrum and treatment of MRSA infections in children in the context of recent epidemiological changes of MRSA infections. In general, community-associated (CA) MRSA most frequently causes skin and soft tissue infections and has an increased association with invasive infections, particularly pneumonia and musculoskeletal infections. Hospital-associated (HA) MRSA strains tend to be associated with bloodstream infections, pneumonia, and surgical site infections. Different from the United States, CA-MRSA infections are not common in Korea (only 5.9%); however, there are some CA-MRSA clones that are different from HA-MRSA clones in Korea and from CA-MRSA clones in other countries. The treatment of MRSA infections should be guided by antimicrobial susceptibility testing, the site of infection, and the infection severity. Vancomycin is the treatment of choice for invasive MRSA infections. Other agents such as trimethoprim-sulfamethoxazole, clindamycin, linezolid, quinupristin-dalfopristin, and daptomycin have been used for some conditions.

• Biomedical Science Letters
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• v.5 no.2
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• pp.213-217
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• 1999

In order to control resistant strains and to properly select the antimicrobial agents, it is of quite importance to know current trends of bacterial species and changing patterns of antimicrobial resistance rates. The authors studied the results of 542 Gram-positive strains among 1,689 strains isolated at Chung-buk National University Hospital in 1996. The frequently isolated Gram-positive microorganisms were Staphylococcus aureus, Streptococcus pneumoniae, Staphylococcus epidermidis and Enterococcus faecalis in descending order. S. aureus showed high resistance to penicillin, gentamicin, and susceptibility to teicoplanin and vancomycin. Coagulase negative Staphylococcus was highly resistant to all of the antibiotics used in this experiment except teicoplanin and vancomycin. Enterococcus were highly resistant to vancomycin, penicillin and tetracycline. MIC of Gram-positive oaganisms was appeared to be zig-zag pattern.

• Journal of Korean Neurosurgical Society
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• v.43 no.6
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• pp.307-310
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• 2008

Limited therapeutic options are available for vancomycin intermediate-resistant Staphylococcus epidermidis (VISE) infections and no optimum therapy has been established. We report a case of VISE skull osteomyelitis that was successfully treated with linezolid. The patient was a 53-year-old man who presented with headache, nausea and dysphasia. Brain computerized tomography (CT) demonstrated a subdural hematoma in the left hemisphere. Craniotomy and hematoma evacuation was performed and he showed good recovery despite a scalp wound infection caused by methicillin-resistant Staphylococcus aureus (MRSA). The organism isolated from the scalp wound was sensitive to vancomycin. The patient was treated with intravenous vancomycin for 44 days. However, he showed a high fever, persistent positive methicillin-resistant Staphylococcus epidermidis (MRSE) blood cultures, and a deteriorating clinical status. He underwent infected skull bone flap removal and linezolid treatment for 35 days. During one year of follow up, he has not had any further episodes of osteomyelitis or fever. Linezolid has shown to be effective agent to eradiate osteomyelitis caused by VISE.

• Pediatric Infection and Vaccine
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• v.16 no.2
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• pp.205-209
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• 2009

Staphylococcal toxic shock syndrome (TSS) is a severe systemic illness caused by toxins produced by Staphylococcus aureus. We report a case of staphylococcal TSS in a 16 month-old boy who presented with high fever, vomiting, skin rash, and shock after a burn injury. He was managed with intravenous vancomycin, fresh frozen plasma, and intravenous immunoglobulin. Methicillin-resistant S. aureus (MRSA) was isolated from the burn wound site and anterior nostril of the patient. In addition, the MRSA isolate was genetically characterized.