Staphylococcus aureus and Staphylococcus epidermidis strains isolated at eight large medical centers in Korea were examined for methicillin resistance and resistance to eight other antibiotics; cefazolin, cefamandole, cefuroxime, cefoxitin, cefotaxime, moxalactam, penicillin G and vancomycin. Methicillin resistance was found in 296 of 1225 strains (24.2%) of S. aureus and 126 of 348 strains (36.2%) of S. epidermidis. Methicillinresistant strains were isolated from all sources with the frequency of isolation ranging from 11% to 60%. From pleural effusion, throat swab and blood, methicillin-resistant strains of S. aureus were more frequently isolated with statistical significance (Chi-squared test, 95% confidence). Almost all of Methicillin-resistant S. aureus (MRSA) and S. epidermidis (MRSE) strains were multiply resistant to one or more tested eight antibiotics. However only 7(2.4%) of 296 MRSA strains and 2(1.6%) of 126 MRSE strains were resistant to vancomycin. Vancomycin was the most effective antibiotic against staphylococcal isolates as well as MRSA and MRSE.
Anti-Bacterial Agents/*pharmacology ; Cross Infection/microbiology ; Drug Resistance, Microbial ; Humans ; Korea ; Staphylococcal Infections/microbiology ; Staphylococcus aureus/*drug effects/isolation & purification ; Staphylococcus epidermidis/*drug effects/isolation & purification

The oral microbial community is widely regarded as a latent reservoir of antibiotic resistance genes. This study assessed the molecular epidemiology, susceptibility profile, and resistance mechanisms of 35 methicillin-resistant Staphylococcus epidermidis (MRSE) strains isolated from the dental plaque of a healthy human population. Broth microdilution minimum inhibitory concentrations (MICs) revealed that all the isolates were nonsusceptible to oxacillin and penicillin G. Most of them were also resistant to trimethoprim (65.7%) and erythromycin (54.3%). The resistance to multiple antibiotics was found to be largely due to the acquisition of plasmid-borne genes. The mecA and dfrA genes were found in all the isolates, mostly dfrG (80%), aacA-aphD (20%), aadD (28.6%), aphA3 (22.9%), msrA (5.7%), and the ermC gene (14.3%). Classical mutational mechanisms found in these isolates were mainly efflux pumps such as qacA (31.4%), qacC (25.7%), tetK (17.1%), and norA (8.6%). Multilocus sequence type analysis revealed that sequence type 59 (ST59) strains comprised 71.43% of the typed isolates, and the eBURST algorithm clustered STs into the clonal complex 2-II(CC2-II). The staphyloccoccal cassette chromosome mec (SCCmec) type results showed that 25 (71.43%) were assigned to type IV. Moreover, 88.66% of the isolates were found to harbor six or more biofilm-associated genes. The aap, atlE, embp, sdrF, and IS256 genes were detected in all 35 isolates. This research demonstrates that biofilm-positive multiple-antibiotic-resistant ST59-SCCmec IV S. epidermidis strains exist in the dental plaque of healthy people and may be a potential risk for the transmission of antibiotic resistance.
Anti-Bacterial Agents ; therapeutic use ; Dental Plaque ; microbiology ; Female ; Humans ; Methicillin ; Methicillin-Resistant Staphylococcus aureus ; isolation & purification ; Staphylococcal Infections ; diagnosis ; Staphylococcus epidermidis ; isolation & purification

OBJECTIVETo study the pathogen distribution and risk factors of nosocomial infections in neonates in the neonatal intensive care units (NICU).

METHODSThe clinical data of 145 neonates with nosocomial infection in the NICU were retrospectively reviewed.

RESULTSOf the 145 neonates, 41 (28.3%) were infected with Klebsiella pneumoniae, 39 (26.9%) with Escherichia coli, 10 (6.9%) with Staphylococcus epidermidis, and 55 (37.9%) with other pathogens. Logistic regression analysis showed that a gestational age of ≤32 weeks (OR=5.57), birth weigh of <1500 g (OR=6.95), hospitalization time (OR=1.23), mechanical ventilation (OR=14.12) and parenteral nutrition (OR=3.01) were major risk factors for nosocomial infections caused by Klebsiella pneumoniae. The five factors were also main risk factors for nosocomial infection caused by Escherichia coli, with the OR of 3.42, 6.73, 9.96, 0.55 and 2.13 respectively. Klebsiella pneumoniae and Escherichia coli were highly resistant to β-lactam antibiotics but were relatively sensitive to levofloxacin and meropenem.

CONCLUSIONSKlebsiella pneumoniae, Escherichia coli and Staphylococcus epidermidis are major pathogens of nosocomial infections in neonates in the NICU and they are resistant to β-lactam antibiotics. Mechanical ventilation and hospitalization time are the most important risk factors for nosocomial infections caused by Klebsiella pneumoniae and Escherichia coli respectively.

Bacteria ; isolation & purification ; Cross Infection ; drug therapy ; etiology ; microbiology ; Drug Resistance, Bacterial ; Escherichia coli ; isolation & purification ; Female ; Humans ; Infant, Newborn ; Intensive Care Units, Neonatal ; Klebsiella pneumoniae ; isolation & purification ; Logistic Models ; Male ; Risk Factors ; Staphylococcus epidermidis ; isolation & purification

OBJECTIVEDespite progress in antibiotic therapy and intensive care, childhood bacterial meningitis (BM) remains a devastating disease. We conducted this study to investigate the changes in clinical characteristics, the etiologic agents and antimicrobial susceptibility of BM during the past 10 years in children under 14 years of age.

METHODSThese 126 patients were divided into two groups according to their date of admission. Group 1 included 64 patients admitted from January 1998 to December 2002, and group 2 included 62 cases admitted from January 2003 to December 2007. All pediatric medical charts of them were reviewed.

RESULTSThe predominant isolated bacteria from CSF were coagulase-negative staphylococcus (17/62, 27.4%) and Escherichia coli (9/62, 14.5%) in group 2. The resistance rate of staphylococcus against oxacillin (MRS) was 68.4% (13/19) in group 2, significantly higher than that of group 1 (16.7%, 2/12). Among 126 cases, 42 had seizure attack and 16 had consciousness disturbance, the proportions of them in group 2 (11/62, 17.7%; 4/62, 6.4%) were lower than those in group 1 (31/64, 48.4%; 12/64, 18.8%, P < 0.05). Cases in group 2 survived with complications [13/62 (21.0%)] and sequelae [11/62 (17.7%)] were lower than those in group 1 (24/64, 37.5%, 23/64, 35.9%, P < 0.05), but the rate of empirical therapy modification in group 2 (21/62, 33.9%) was higher than that in group 1 (7/64, 10.9%, P < 0.01).

CONCLUSIONThe predominant bacteria in children with BM are staphylococcus and Escherichia coli in recent years. The antibiotic resistance rate of bacteria has been higher year after year. The clinical patterns of pediatric BM have changed with a decrease in clinically serious cases, complications and sequelae, but an increase in modification of empirical therapy.

Anti-Bacterial Agents ; pharmacology ; Child ; Child, Preschool ; Cross Infection ; microbiology ; Drug Resistance, Bacterial ; Escherichia coli ; drug effects ; isolation & purification ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial ; epidemiology ; microbiology ; Retrospective Studies ; Staphylococcus epidermidis ; drug effects ; isolation & purification

The crude extracts of the fermentation broth from a marine sediment-derived actinomycete strain, Saccharothrix sp. 10-10, showed significant antibacterial activities against drug-resistant pathogens. A genome-mining PCR-based experiment targeting the genes encoding key enzymes involved in the biosynthesis of secondary metabolites indicated that the strain 10-10 showed the potential to produce tetracenomycin-like compounds. Further chemical investigation of the cultures of this strain led to the identification of two antibiotics, including a tetracenomycin (Tcm) analogs, Tcm X (1), and a tomaymycin derivative, oxotomaymycin (2). Their structures were identified by spectroscopic data analysis, including UV, 1D-NMR, 2D-NMR and MS spectra. Tcm X (1) showed moderate antibacterial activities against a number of drug-resistant pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) pathogens, with the MIC values in the range of 32-64 microg x mL(-1). In addition, 1 also displayed significant cytotoxic activities against human cancer cell lines, including HL60 (leukemia), HepG2 (liver), and MCF-7 (breast) with the IC 50 values of 5.1, 9.7 and 18.0 micromol x L(-1), respectively. Guided by the PCR-based gene sequence analysis, Tcm X (1) and oxotomaymycin (2) were identified from the genus of Saccharothrix and their 13C NMR data were correctly assigned on the basis of 2D NMR spectroscopic data analysis for the first time.
Actinomycetales ; chemistry ; genetics ; Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; Benzodiazepinones ; chemistry ; isolation & purification ; pharmacology ; Cell Line, Tumor ; Data Mining ; methods ; Drug Resistance, Bacterial ; Enterococcus faecalis ; drug effects ; Fermentation ; Genomics ; Humans ; Inhibitory Concentration 50 ; Marine Biology ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; Microbial Sensitivity Tests ; Molecular Structure ; Naphthacenes ; chemistry ; isolation & purification ; pharmacology ; Phylogeny ; Staphylococcus epidermidis ; drug effects

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Azithromycin ; pharmacology ; Bacteremia ; microbiology ; Child ; Child, Preschool ; Culture Media ; Drug Resistance, Bacterial ; Drug Resistance, Multiple, Bacterial ; Escherichia coli ; drug effects ; isolation & purification ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Methicillin Resistance ; Middle Aged ; Penicillin G ; pharmacology ; Salmonella paratyphi A ; drug effects ; isolation & purification ; Staphylococcus aureus ; drug effects ; isolation & purification ; Staphylococcus epidermidis ; drug effects ; isolation & purification

Sclerosing peritonitis is an uncommon complication of peritoneal dialysis. It is characterized by peritoneal fibrosis and sclerosis. The most common clinical presentations of sclerosing peritonitis in peritoneal dialysis patients are ultrafiltration failure and small bowel obstruction. The prognosis and response to immunosuppressive therapy of sclerosing peritonitis presenting with ultrafiltration failure or small bowel obstruction are poor. Here, we describe the case of a 28-yr-old man with end-stage renal disease on peritoneal dialysis showing fulminant sclerosing peritonitis presented like acute culture-negative peritonitis and was successfully treated with corticosteroid therapy. It is not well recognized that sclerosing peritonitis may present in this way. The correct diagnosis and corticosteroid therapy may be life-saving in a fulminant form of sclerosing peritonitis.
Acute Disease ; Adult ; Anti-Inflammatory Agents/therapeutic use ; Humans ; Kidney Failure, Chronic/therapy ; Male ; Peritoneal Dialysis/adverse effects ; Peritonitis/*diagnosis/drug therapy/etiology ; Prednisolone/therapeutic use ; Sclerosis ; Staphylococcus epidermidis/isolation & purification ; Tomography, X-Ray Computed

The sequences of the ccrAB genes from bovine-, canine- and chicken-originating methicillin-resistant Staphylococcus (S.) epidermidis (MRSE) and bovine methicillin-resistant Staphylococcus (S.) aureus (MRSA) were compared to investigate the frequency of intra-species horizontal transfer of the staphylococcal cassette chromosome mec (SCCmec) complex. Nineteen MRSE strains were isolated from bovine milk, chickens, and dogs, and their genetic characteristics were investigated by multilocus sequence typing and SCCmec typing. Among the animal MRSE strains, the most frequent SCCmec type was type IV, which consisted of the type B mec complex and ccrAB type 2. The ccrA2 and ccrB2 genes were sequenced from the bovine, chicken and canine MRSE strains and compared with those of the bovine MRSA strains. The sequences generally clustered as MRSA and MRSE groups, regardless of the animal source. Additionally, no bovine MRSE sequence was associated with the bovine MRSA groups. Although most of the bovine MRSE and MRSA isolates possessed SCCmec type IV sequences, our results suggest that the intra-species gene transfer of the SCCmec complex between bovine S. aureus and bovine S. epidermidis strains is not a frequent event.
Animals ; Anti-Bacterial Agents/*pharmacology ; Bacterial Proteins/*genetics/metabolism ; Bacterial Typing Techniques/veterinary ; Cattle ; Cattle Diseases/epidemiology/metabolism ; Chickens ; Dog Diseases/epidemiology/metabolism ; Dogs ; *Drug Resistance, Bacterial ; *Gene Transfer, Horizontal ; Methicillin/*pharmacology ; Methicillin-Resistant Staphylococcus aureus/genetics/isolation & purification ; Milk/microbiology ; Multilocus Sequence Typing/veterinary ; Poultry Diseases/epidemiology/metabolism ; Prevalence ; Republic of Korea/epidemiology ; Staphylococcal Infections/epidemiology/microbiology/*veterinary ; Staphylococcus epidermidis/genetics/isolation & purification

The effect and safety of anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach were assessed in the single-level lumbar pyogenic spondylodiscitis. Seventeen patients from 2007 to 2009 underwent anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach. Postoperative follow-up time was 24-41 months. Data included the patients' general information, microbiology, operative time, intraoperative blood loss, postoperative complications, intervertebral fusion rate, and preoperative and final follow-up scores for American Spinal Injury Association (ASIA) impairment, visual analogue scale (VAS), and Oswestry Disability Index (ODI). Ten patients had undergone a prior spinal invasive procedure, and 7 had hematogenous infection. The infected segments included L1-2, L2-3, L3-4, and L4-5 in 1, 2, 5, and 9 cases, respectively. Thirteen bacterial cultures were positive for Staphylococcus aureus (5 cases), Staphylococcus epidermidis (4), Streptococcus (3), and Escherichia coli (1). The operative time was 213.8±45.6 min, and the intraoperative blood loss was 180.6±88.1 mL. Postoperative complications consisted of urinary retention (2 cases), constipation (3), and deep vein thrombosis (2). On the final follow-up, VAS scores and ODIs were significantly lower than those of preoperation, while the ASIA grades improved. All the cases achieved good intervertebral bony fusion. Anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach can successfully treat single-level lumbar pyogenic spondylodiscitis, with less trauma and reliable immobilization. It is a viable option for clinical application.
Adult ; Aged ; Back Pain ; complications ; prevention & control ; Bacterial Infections ; complications ; microbiology ; Constipation ; etiology ; Debridement ; adverse effects ; methods ; Disability Evaluation ; Discitis ; complications ; surgery ; Escherichia coli ; isolation & purification ; Female ; Follow-Up Studies ; Humans ; Lumbar Vertebrae ; microbiology ; surgery ; Male ; Middle Aged ; Minimally Invasive Surgical Procedures ; adverse effects ; methods ; Pain Measurement ; Retrospective Studies ; Spinal Fusion ; adverse effects ; methods ; Staphylococcus aureus ; isolation & purification ; Staphylococcus epidermidis ; isolation & purification ; Streptococcus ; isolation & purification ; Treatment Outcome ; Urinary Retention ; etiology ; Venous Thrombosis ; etiology

OBJECTIVETo evaluate the usefulness of a broad-range real-time PCR assay aimed at the 16S rRNA gene of bacteria in a clinical setting in rapid and reliable diagnosis of neonatal septicemia for improving the speed and accuracy of bacterial detection.

METHODSThe universal primer and TaqMan probe were designed based on the highly conserved sequences of the bacterial 16S rRNA gene. The chosen primers and probe did not show any likely cross hybridization with human, viral or fungal genome sequences. The TaqMan assay used the fluorescent signal on the probe, such as 6-carboxyfluorescin (6-FAM), and quenched by the standard 6-carboxytetramethylrhodamine (TAMRA) probes. The broad-range 16S rRNA gene real-time PCR array was established. Then, three common pathogenic microorganisms including Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli, which were prepared by a 10-fold dilution series respectively from 10(8) colony forming unit (CFU)/ml to 10(3) CFU/ml, as well as controls, were used for testing of both sensitivity and specificity of the real-time PCR assay. The blood samples from 830 cases of suspected septicemia, who were hospitalized in our neonatal ward and the neonatal intensive care unit (NICU) and developed clinical signs suggestive of infection, were tested with routine culture and bacterial 16S rRNA genes real-time PCR separately. In addition, 30 neonates without infection were enrolled as the negative control group.

RESULTSAll the three common pathogenic bacterial species were positive on the 16S rRNA genes real-time PCR assay. There were no cross-reaction with cytomegalovirus (CMV), Epstein-Barr virus (EBV), hepatitis B virus (HBV), fungi, human DNA and blank control, and the technique showed high specificity and sensitivity. The detection limit of the TaqMan assay was tested by amplifying serial dilutions of the three common pathogenic bacterial DNA. The minimal detection limit of the TaqMan system was equivalent to 3 CFU of bacteria, the threshold cycle (CT), which is inversely proportional to the log of the amount of target DNA initially present, was 37.90 by calculation. The real-time PCR assay was evaluated on 830 blood specimens for suspected neonatal septicemia, as compared to the results obtained from the routine bacterial cultures. The positive rate by the real-time PCR assay was 5.18% (43/830) in 830 samples, and was significantly higher than that of blood culture [2.41% (20/830) (P < 0.01)]. The real-time PCR was positive in all the 20 positive blood culture samples. Thirty non-infectious blood samples were negative by both the PCR assay and blood cultures. When blood culture was used as control, the sensitivity of the real-time PCR assay was 100%, the specificity was 97.16%, and the index of accurate diagnosis was 0.972. Moreover, three of the PCR positive amplicons were confirmed by sequencing to confirm the accuracy of the real-time PCR assay in testing clinical specimens. The sequencing showed that except for one sequence, all the others were demonstrated to be Staphylococcus aureus and Escherichia coli respectively, which was in accord with the results of the blood cultures.

CONCLUSIONSThe bacterial 16S rRNA genes real-time PCR had been established to diagnose the neonatal septicemia. The sensitivity and specificity the real-time PCR assay were higher than those of blood culture. This technique can provide a rapid way for the etiological diagnosis of neonatal septicemia, and was a convenient and accurate method in etiologic diagnosis of neonatal septicemia.

DNA ; analysis ; DNA Primers ; Escherichia coli ; genetics ; Genes, rRNA ; genetics ; Herpesvirus 4, Human ; genetics ; isolation & purification ; Humans ; Infant, Newborn ; Limit of Detection ; Nucleic Acid Hybridization ; Polymerase Chain Reaction ; methods ; RNA, Ribosomal, 16S ; analysis ; Rhodamines ; Sensitivity and Specificity ; Sepsis ; diagnosis ; genetics ; Sequence Analysis, DNA ; Staphylococcus aureus ; genetics ; Staphylococcus epidermidis ; genetics