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

No abstract available.
Glycopeptides*

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

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

BACKGROUND: Recent hospital environments have changed, and the most common and important causative agents of nosocomial infections are Gram positive organisms, such as staphylococci, streptococci and enterococci. And increasing resistance of such Gram-positive organisms to antimicrobials, including glycopeptides, is causing big problems in hospital infections. Therefore, we confirmed and compared the antimicrobial activities of glycopeptides [Tapocin(r) (CJ Pharmaceutics. Korea), vancomycin, teicoplanin] against clinical isolates of streptococci(PSSP, PNSSP), staphylococci (MSSA, MRSA, MRCNS) and enterococci. METHODS: Total 666 strains of Gram-positive cocci, collected in five Catholic University affiliated Hospitals were tested by broth microdilution method using Muller-Hinton broth according to the recommendation of NCCLS (National Committee for Clinical Laboratory Standard, USA). RESULTS: In PSSP (n=46), MIC range of vancomycin was 0.25-0.5 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.015-0.06 microgram/mL. MIC90 of vancomycin was 0.5 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.06 microgram/mL. In PNSSP (n=123), MIC range of vancomycin was 0.25-0.5 microgram/mL, and MIC range of Tapocin(r) and teicoplanin was equally 0.03-0.06 microgram/mL. The MIC range of vancomycin against MSSA (n=116) was 2-4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.5-8 microgram/mL. MIC90 of vancomycin was 4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 2 microgram/mL. In MRSA (n=116), MIC range of Tapocin(r) and teicoplanin was equally 0.25-8 microgram /mL, showing broader range distribution than that of vancomycin (2-4 microgram/mL). MIC90 of vancomycin was 4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 8 microgram/mL. MIC range against MRCNS (n=14) of vancomycin was 0.25-8 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.06- 16 microgram/mL. In enterococci (n=123), the MIC range of vancomycin was 0.5-64 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.25-64 microgram/mL. MIC90 of all antibiotics was 8 microgram/mL, but 6 E. faecium resistant to all antibiotics were detected. CONCLUSION: The results of susceptibility tests showed that the against glycopeptides against Gram- positive cocci, which were isolated in our study university hospitals, seem to be largely unaffected. We also confirmed that the antimicrobial activity of Tapocin(r) was equal to that of teicoplanin.
Anti-Bacterial Agents ; Cross Infection ; Glycopeptides ; Gram-Positive Cocci* ; Hospitals, University ; Methicillin-Resistant Staphylococcus aureus ; Microbial Sensitivity Tests ; Teicoplanin ; Vancomycin

BACKGROUND: Recent hospital environments have changed, and the most common and important causative agents of nosocomial infections are Gram positive organisms, such as staphylococci, streptococci and enterococci. And increasing resistance of such Gram-positive organisms to antimicrobials, including glycopeptides, is causing big problems in hospital infections. Therefore, we confirmed and compared the antimicrobial activities of glycopeptides [Tapocin(r) (CJ Pharmaceutics. Korea), vancomycin, teicoplanin] against clinical isolates of streptococci(PSSP, PNSSP), staphylococci (MSSA, MRSA, MRCNS) and enterococci. METHODS: Total 666 strains of Gram-positive cocci, collected in five Catholic University affiliated Hospitals were tested by broth microdilution method using Muller-Hinton broth according to the recommendation of NCCLS (National Committee for Clinical Laboratory Standard, USA). RESULTS: In PSSP (n=46), MIC range of vancomycin was 0.25-0.5 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.015-0.06 microgram/mL. MIC90 of vancomycin was 0.5 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.06 microgram/mL. In PNSSP (n=123), MIC range of vancomycin was 0.25-0.5 microgram/mL, and MIC range of Tapocin(r) and teicoplanin was equally 0.03-0.06 microgram/mL. The MIC range of vancomycin against MSSA (n=116) was 2-4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.5-8 microgram/mL. MIC90 of vancomycin was 4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 2 microgram/mL. In MRSA (n=116), MIC range of Tapocin(r) and teicoplanin was equally 0.25-8 microgram /mL, showing broader range distribution than that of vancomycin (2-4 microgram/mL). MIC90 of vancomycin was 4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 8 microgram/mL. MIC range against MRCNS (n=14) of vancomycin was 0.25-8 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.06- 16 microgram/mL. In enterococci (n=123), the MIC range of vancomycin was 0.5-64 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.25-64 microgram/mL. MIC90 of all antibiotics was 8 microgram/mL, but 6 E. faecium resistant to all antibiotics were detected. CONCLUSION: The results of susceptibility tests showed that the against glycopeptides against Gram- positive cocci, which were isolated in our study university hospitals, seem to be largely unaffected. We also confirmed that the antimicrobial activity of Tapocin(r) was equal to that of teicoplanin.
Anti-Bacterial Agents ; Cross Infection ; Glycopeptides ; Gram-Positive Cocci* ; Hospitals, University ; Methicillin-Resistant Staphylococcus aureus ; Microbial Sensitivity Tests ; 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*

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: Several risk factors related with vancomycin-resistant Enterococcus (VRE) colonization are well known, but the direct relatedness of the use of glycopeptides with VRE colonization is not confirmed yet. So we evaluated the influence of the use of glycopeptides and other variables, as risk factors on intestinal colonization with VRE. METHODS: In glycopeptide-administered inpatients group, multiple stool specimens were collected on the day of glycopeptides administration, and weekly after that, until VRE were detected. In the inpatients and outpatients control groups, stool were obtained with point survey. The specimens were inoculated on m-enterococcus agar with 6mg/L vancomycin. The phenotypes and genotypes of resistance of the VRE isolates were confirmed by disk diffusion and agar dilution tests, and polymerase chain reaction. RESULTS: Of the 361 patients(530 specimens), twelve VRE(3.3%) were isolated. The rates of intestinal colonizations were not significantly differed between the inpatients groups with or without glycopeptides administration, which are 5.1 and 4.1%, respectively. The colonization rates were significantly higher in the patients with 30 or more hospital stay, and in those with three or more antimicrobial administrations. vanA and vanC genes were amplified in the isolates. CONCLUSIONS: It is demonstrated that the use of glycopeptides is not a direct risk factor of intestinal colonization of VRE in Pusan National University Hospital, in which the prescription of glycopeptides is rigidly controlled. But, a shortened stay in the hospital will diminish the intestinal colonization of VRE.
Agar ; Busan ; Colon* ; Diffusion ; Enterococcus* ; Genotype ; Glycopeptides* ; Humans ; Inpatients ; Length of Stay ; Outpatients ; Phenotype ; Polymerase Chain Reaction ; Prescriptions ; Risk Factors* ; Vancomycin

Glycopeptides ; Heart Failure ; Humans ; Hydrogen Sulfide