No abstract available.
Glycopeptides*

Glycopeptides ; Heart Failure ; Humans ; Hydrogen Sulfide

BACKGROUND: We tried to evaluate the incidence and clinical significance of coagulase-negative staphylococci (CoNS) with reduced susceptibilities to glycopeptides. In addition, the ability of disk diffusion and Vitek system to detect CoNS with reduced susceptibilities to glycopeptides were compared with the standard agar dilution method. METHODS: One hundred and nineteen clinical isolates of CoNS were recovered at Samsung Medical Center from June to July 1998 and were examined for their susceptibilities to vancomycin and teicoplanin by disk diffusion method (30-microgram disk), Vitek system with GPS-AA card, and agar dilution for the determination of MICs. The records of all patients, from whom CoNS with decreased susceptibility to glycopeptide was isolated, were reviewed. RESULTS: All CoNS showed uniform susceptibility to vancomycin by all three methods but 11 strains (9.2%) exhibited reduced susceptibilities to teicoplanin (MICs, 16 to 32 microgram/mL). All but suspected colonized strains were nosocomially acquired and were isolated from 7 different wards. None were previously treated with teicoplanin. The concordance rates of disk diffusion method and Vitek system with agar dilution method were 94.1% and 84%, respectively. However, the sensitivity of disk diffusion method and Vitek system were only 50.0% and 62.5%, respectively. CONCLUSIONS: This study demonstrates that CoNS with reduced susceptibilities to glycopeptides is not uncommon and may cause true infections in clinical settings. However, neither disk diffusion method nor Vitek system could differentiate these strains from more susceptible isolates.
Agar ; Colon ; Diffusion ; Glycopeptides* ; Humans ; Incidence* ; Teicoplanin ; Vancomycin

BACKGROUND: Teicoplanin is a glycopeptide antimicrobial agent effective against methicillin-resistant staphylococci. Decreased susceptibility of staphylococci to glycopeptides has been increasing. Teicoplanin diffuses poorly in agar and therefore the correlation between the inhibition zone diameter and the minimal inhibitory concentration(MIC) is rather poor. The purpose of this study was to evaluate the prevalence of teicoplanin-resistant staphylococci and to assess the reliability of inhibition zone diameters for determining the susceptibility of staphylococci to teicoplanin by comparing the results of the agar dilution MICs. METHODS: From June to August 1997, 290 clinical isolates of staphylococci(77 coagulase negative staphylococci(CNS), 213 Staphylococcus aureus) were collected. The antimicrobial susceptibilities to teicoplanin were determined by inhibition zone diameter and the results were compared with the MICs determined by the agar dilution method. RESULTS: Among 77 CNS strains, 75(97.4%) were susceptible and 2(2.6%) were intermediate by agar dilution method and all 213 strains of S. aureus were susceptible to teicoplanin. There was a poor correlation(r=0.50) between the zone diameters of inhibition and agar dilution MICs. In comparison with the results of disk diffusion test and agar dilution MIC, eight (2.8%) out of 290 isolates showed discrepancies (major error rates : 0.3%, minor error rates: 2.4%). CONCLUSIONS: Two(2.6%) out of 77 strains of CNS and none of 213 S. aureus strains revealed decreased susceptibility to teicoplanin. And the inhibition zone diameter was less reliable in determining the susceptibility of staphylococci than MICs. Therefore, the more effective and convenient method is needed.
Agar ; Coagulase ; Diffusion* ; Glycopeptides ; Methicillin Resistance ; Prevalence* ; Staphylococcus ; Teicoplanin*

Nano-LC-MS/MS was used to analyze trypsin digested deer-horn gelatin( DCG) and deer-hide gelatin( DHG) samples.The glycopeptides in DCG and DHG were quantified by Label-free quantitative( LFQ) peptidomics,on the basis of which the glycopeptides with significant difference in DCG and DHG were determined. As a result,5 736 peptides were identified from DCG samples,including 213 galactosyl-hydroxylysine containing peptides( Gal-Hyl-peptides) and 102 glucosyl-galactosyl-hydroxylysine containing peptides( Glc-Gal-Hyl-peptides),while 6 836 peptides were identified from DHG samples,among which there were 250 Gal-Hyl-peptides and 98 Glc-Gal-Hyl-peptides. With over 3-fold peak area difference and highly significant intergroup difference( P < 0. 01) as the screening criteria,444 differential peptides were determined in DCG and DHG,including 16 Gal-Hyl-peptides and 5 Glc-Gal-Hyl-peptides. Then XIC peak shapes,standard deviation of peak area,and fold change were applied for further screening and 5 glycopeptides with significant differences in DCG and DHG were confirmed,which could serve as potential biomarkers for distinguishing DCG and DHG. The present study provided ideas and strategies for the in-depth investigation on the discrimination of DCG and DHG and is of good theoretical significance and application value for the further research on chemical constituents and quality control of gelatin derived Chinese medicinals.
Animals ; Chromatography, Liquid ; Deer ; Gelatin ; Glycopeptides ; Tandem Mass Spectrometry

With increased infection by methicillin-resistant staphylococci, the use of glycopeptides has been increasing. Recently, staphylococci with decreased susceptibility to glycopeptides, especially teicoplanin, are increasingly reported. We isolated a Staphylococcus aureus strain isolated repeatedly from a wound culture, which showed susceptibility to teicoplanin by the disk diffusion method but showed growth on the Mueller-Hinton agar containing 6 g/mL of teicoplanin. This strain was clinically resistant to treatment at 200 mg/day of teicoplanin. By changing the treatment into combining rifampin (600 mg/day) and increasing the dose of teicoplanin (400 mg/day), the S. aureus was not isolated any more.
Agar ; Diffusion ; Glycopeptides ; Methicillin Resistance ; Rifampin ; Staphylococcus aureus* ; Staphylococcus* ; Teicoplanin* ; Wound Infection* ; Wounds and Injuries*

BACKGROUND: The purpose of this study was to investigate the prevalence of Stap hylococcus aureus with decreased susceptibility to glycopeptides in Korea and to evaluate the methods for detection. METHODS: From March to May 1998, 106 clinical isolates of S. aureus were collected from patients of the Kosin Medical Center . Antimicrobial susceptibilities for vancomycin and teicoplanin were determined by NCCLS disc diffusion method and the MICs were determined by agar dilution method. Correlation between both results was evaluated. RESULTS: MICs of vancomycin and teicoplanin against S. aureus isolates were 0.5 ~2 microgram/mL and 0.25 ~8 microgram/mL. Some S. aureus isolates showed decreased susceptibility to teicoplanin (MIC 4 microgram/mL, 33 strains; MIC 8 microgram/mL, 1 strain), but none showed decreased susceptibility to vancomycin. A positive correlation was observed between the inhibitory zone diameters of teicoplanin disc and the MICs of teicoplanin(P< 0.0 1). Inhibitory zone diameter differences between vancomycin and teicoplanin discs also showed a positive correlation with the MICs of teicoplanin (P< 0.01). Strains whose inhibitory zone diameters of teicoplanin disc were less than 16 mm, the sensitivity and positive predictive value for the detection of strains with MICs more than 4 microgram/mL were 100 % (34/ 34) and 43% (34/ 79), respectively. In strains with inhibitory zone diameter difference of more than 4 mm, the sensitivity and positive predictive value of detection in MICs of more than 4 microgram/mL were 94 % (32/ 34) and 70 % (32/46), respectively. CONCLUSION: Although S. aureus with intermediate or full resistance to glycopeptides was not isolated in this study, few strains had decreased susceptibility to teicoplanin. We conclude that when the inhibitory zone diameters of teicoplanin disc are less than 16 mm or inhibitory zone diameter difference between vancomycin and teicoplanin discs is more than 4 mm, the presence of S. aureus isolates with decreased susceptibility to teicoplanin should be suspected.
Agar ; Diffusion ; Glycopeptides ; Humans ; Korea ; Prevalence ; Staphylococcus aureus* ; Staphylococcus* ; Teicoplanin* ; Vancomycin

Arbekacin is a broad-spectrum aminoglycoside used to treat methicillin-resistant Staphylococcus aureus (MRSA). Arbekacin has antibacterial activities against high-level gentamicin-resistant Enterococci, multidrug-resistant Pseudomonas aeruginosa, and Acinetobacter baumannii et al. Here, we reviewed in vitro data on arbekacin in Staphylococci and Gram-negative microorganisms. We also reviewed clinical studies for clinical efficacy and microbiologic efficacy data in patients with identified MRSA and suspected MRSA infections. The overall clinical efficacy ranged from 66.7% to 89.7%. The microbiologic efficacy rate ranged from 46.2% to 83%. In comparative studies between arbekacin and glycopeptides, arbekacin was similar to other glycopeptides with respect to clinical and microbiological efficacy rates. Combination trials with other antibiotics suggest that arbekacin will be a promising strategy to control Enterococcus spp. multi-drug resistant P. aeruginosa. The major adverse reaction was nephrotoxicity/hepatotoxicity, but patients recovered from most adverse reactions without any severe complications. Based on these results, arbekacin could be a good alternative to vancomycin/teicoplanin in MRSA treatment. Finally, therapeutic drug monitoring is recommended to maximize clinical efficacy and decrease nephrotoxicity.
Acinetobacter baumannii ; Anti-Bacterial Agents ; Drug Monitoring ; Enterococcus ; Glycopeptides ; Humans ; Methicillin-Resistant Staphylococcus aureus ; Pseudomonas aeruginosa

Glycopeptides of the clinically important antibiotic drugs are glycosylated cyclic or polycyclic nonribosomal peptides. Glycopeptides such as vancomycin and teicoplanin are often used for the treatment of gram-positive bacteria in patients. The increased incidence of drug resistance and inadequacy of these therapeutics against gram-positive bacterial infections would be the formation and clinical development of more variable second generation of glycopeptide antibiotics: semisynthetic lipoglycopeptide analogs such as telavancin, dalbavancin, and oritavancin with improved activity and better pharmacokinetic properties. In this review, we describe the development of and bacterial resistance to vancomycin, teicoplanin, and semisynthetic glycopeptides (teicoplanin, dalbavancin, and oritavancin). The clinical influence of resistance to glycopeptides, particularly vancomycin, are also discussed.
Anti-Bacterial Agents* ; Drug Resistance ; Glycopeptides ; Gram-Positive Bacteria ; Gram-Positive Bacterial Infections ; Humans ; Incidence ; Peptides ; Teicoplanin ; Vancomycin

Recently, infections caused by antibiotic-resistant bacteria continue to climb in the community and the hospital around the world. Our current antimicrobial agents are gradually becoming ineffective and a new pipeline of powerful compounds is needed urgently. A number of new antimicrobial compounds are in development, including novel glycopeptides (dalbavancin, telavancin, and oritavancin), daptomycin, tigecycline, ceftobiprole, iclaprim, and doripenem. The article will provide an update on the newly marketed and potentially effective antibacterial agents in the late-stage development pipeline
Aminoglycosides ; Anti-Bacterial Agents ; Anti-Infective Agents ; Bacteria ; Carbapenems ; Cephalosporins ; Daptomycin ; Drug Resistance ; Drugs, Investigational ; Glycopeptides ; Minocycline ; Pyrimidines ; Trastuzumab