1
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Green DL, Cook JB, Triemer HL, Galloway JR. Vancomycin Concentrations in Necrotic Pancreatic Tissue: A Pilot Study. Hosp Pharm 2017. [DOI: 10.1177/001857870303800909] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Purpose: To determine vancomycin concentrations in necrotic pancreatic tissue of intensive care unit (ICU) patients with acute necrotizing pancreatitis. Methods: The prospective, observational pilot study was conducted at a university-based tertiary hospital. The patient population consisted of 11 patients with necrotizing pancreatitis receiving vancomycin and undergoing necrosectomy. Tissue samples taken during surgical debridement were assayed for vancomycin by immunoassay. Patients were divided into steady state and nonsteady-state groups. Two patients were excluded because necrosectomy was not performed, and one tissue sample could not be assayed because of contamination. Results: The mean tissue concentration was 5.84 mcg/mL (ranging from 3.1 mcg/mL to 8.94 mcg/mL). Four patients in the nonsteady-state group, who each received a single dose of vancomycin, had a mean tissue concentration of 4.5 ± 1.68 mcg/mL, compared with 7.76 ± 1.05 mcg/mL for the four steady-state patients. Conclusion: The data shows that vancomycin is detectable in necrotic pancreas tissue but possibly not in concentrations sufficient to prevent or treat bacterial contamination in patients with pancreatic necrosis.
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Affiliation(s)
- David L. Green
- Department of Pharmaceutical Services; Emory University Hospital, Atlanta, GA
| | | | - Helen L. Triemer
- Kidney Transplant Service, Department of Pharmaceutical Services, Emory University Hospital
| | - John R. Galloway
- Surgical Intensive Care Unit, Department of Surgery, Emory University Hospital. At the time of the study, Dr. Cook was a Pharmacy Practice Resident at Emory University Hospital
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2
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Stockmann C, Roberts JK, Yu T, Constance JE, Knibbe CAJ, Spigarelli MG, Sherwin CMT. Vancomycin pharmacokinetic models: informing the clinical management of drug-resistant bacterial infections. Expert Rev Anti Infect Ther 2015; 12:1371-88. [PMID: 25301231 DOI: 10.1586/14787210.2014.966081] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This review aims to critically evaluate the pharmacokinetic literature describing the use of vancomycin in the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. Guidelines recommend that trough concentrations be used to guide vancomycin dosing for the treatment of MRSA infections; however, numerous in vitro, animal model and clinical studies have demonstrated that the therapeutic effectiveness of vancomycin is best described by the area under the concentration versus time curve (AUC) divided by the minimum inhibitory concentration (MIC) of the infecting organism (AUC/MIC). Among patients with lower respiratory tract infections, an AUC/MIC ≥400 was associated with a superior clinical and bacteriological response. Similarly, patients with MRSA bacteremia who achieved an Etest AUC/MIC ≥320 within 48 h were 50% less likely to experience treatment failure. For other patient populations and different clinical syndromes (e.g., children, the elderly, patients with osteomyelitis, etc.), pharmacokinetic/pharmacodynamic studies and prospective clinical trials are needed to establish appropriate therapeutic targets.
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Affiliation(s)
- Chris Stockmann
- Department of Pediatrics, Division of Clinical Pharmacology, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, Utah 84108, USA
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3
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The msaABCR operon regulates resistance in vancomycin-intermediate Staphylococcus aureus strains. Antimicrob Agents Chemother 2014; 58:6685-95. [PMID: 25155591 DOI: 10.1128/aac.03280-14] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vancomycin-intermediate Staphylococcus aureus (VISA) strains present an increasingly difficult problem in terms of public health. However, the molecular mechanism for this resistance is not yet understood. In this study, we define the role of the msaABCR operon in vancomycin resistance in three clinical VISA strains, i.e., Mu50, HIP6297, and LIM2. Deletion of the msaABCR operon resulted in significant decreases in the vancomycin MIC (from 6.25 to 1.56 μg/ml) and significant reductions of cell wall thickness in strains Mu50 and HIP6297. Growth of the mutants in medium containing vancomycin at concentrations greater than 2 μg/ml resulted in decreases in the growth rate, compared with the wild-type strains. Mutation of the msaABCR operon also reduced the binding capacity for vancomycin. We conclude that the msaABCR operon contributes to resistance to vancomycin and cell wall synthesis in S. aureus.
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4
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Clinical outcome with oral linezolid and rifampin following recurrent methicillin-resistant Staphylococcus aureus bacteremia despite prolonged vancomycin treatment. Can J Infect Dis 2011; 15:97-100. [PMID: 18159483 DOI: 10.1155/2004/768765] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2003] [Accepted: 01/08/2004] [Indexed: 11/18/2022] Open
Abstract
Drug-resistant Gram-positive bacteria, especially Staphylococcus aureus, are emerging as the predominant organisms involved in both nosocomial and community-acquired infections. Since the 1980s, vancomycin has been the first-line antibiotic used to treat methicillin- resistant S aureus. However, allergy and intolerance to vancomycin, the increasing number of vancomycin clinical failures and the existence of vancomycin intermediate-susceptible isolates of S aureus suggest that new antibiotics are needed. This paper reports the only known case of a successful clinical outcome with long term oral linezolid and rifampin therapy in the management of recurrent and persistent methicillin-resistant S aureus bacteremia with metastatic infections despite prolonged vancomycin use. More than two years since the initiation of linezolid and rifampin, the study patient has been clinically well with no evidence of adverse drug reactions including cytopenia and hepatic toxicities. Physicians must be aware of the novel developments in antibiotic therapy to treat drug-resistant bacterial infections.
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5
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Nailor MD, Sobel JD. Antibiotics for gram-positive bacterial infection: vancomycin, teicoplanin, quinupristin/dalfopristin, oxazolidinones, daptomycin, telavancin, and ceftaroline. Med Clin North Am 2011; 95:723-42, vii. [PMID: 21679789 DOI: 10.1016/j.mcna.2011.03.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
An overview of the mechanism of action, dosing, clinical indications, and toxicities of the glycopeptide vancomycin is provided. The emerging gram-positive bacterial resistance to antimicrobials and its mechanisms are reviewed. Strategies to control this emergence of resistance are expected to be proposed. Newer antimicrobial agents that have activity against vancomycin-resistant organisms are now available and play a critical role in the treatment of life-threatening infections.
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Affiliation(s)
- Michael D Nailor
- University of Connecticut School of Pharmacy, 69 North Eagleville Road Unit 3092, Storrs, CT 06269, USA
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6
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Antibiotics for gram-positive bacterial infections: vancomycin, teicoplanin, quinupristin/dalfopristin, oxazolidinones, daptomycin, dalbavancin, and telavancin. Infect Dis Clin North Am 2010; 23:965-82, ix. [PMID: 19909893 DOI: 10.1016/j.idc.2009.06.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
An overview of the mechanism of action, dosing, clinical indications, and toxicities of the glycopeptide vancomycin is provided. The emerging gram-positive bacterial resistance to antimicrobials and its mechanisms are reviewed. Strategies to control this emergence of resistance are expected to be proposed. Newer antimicrobial agents that have activity against vancomycin-resistant organisms are now available and play a critical role in the treatment of life-threatening infections.
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7
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Oshiro T, Ikeda-Dantsuji Y, Nagayama A, Nagasawa Z, Hanaki H. The antagonistic effects of a combination of vancomycin and minocycline in Staphylococcus aureus with heterogeneous resistance to vancomycin. J Infect Chemother 2008; 14:15-22. [DOI: 10.1007/s10156-007-0569-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2007] [Accepted: 10/03/2007] [Indexed: 10/22/2022]
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8
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Cui L, Iwamoto A, Lian JQ, Neoh HM, Maruyama T, Horikawa Y, Hiramatsu K. Novel mechanism of antibiotic resistance originating in vancomycin-intermediate Staphylococcus aureus. Antimicrob Agents Chemother 2006; 50:428-38. [PMID: 16436693 PMCID: PMC1366884 DOI: 10.1128/aac.50.2.428-438.2006] [Citation(s) in RCA: 160] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
As an aggressive pathogen, Staphylococcus aureus poses a significant public health threat and is becoming increasingly resistant to currently available antibiotics, including vancomycin, the drug of last resort for gram-positive bacterial infections. S. aureus with intermediate levels of resistance to vancomycin (vancomycin-intermediate S. aureus [VISA]) was first identified in 1996. The resistance mechanism of VISA, however, has not yet been clarified. We have previously shown that cell wall thickening is a common feature of VISA, and we have proposed that a thickened cell wall is a phenotypic determinant for vancomycin resistance in VISA (L. Cui, X. Ma, K. Sato, et al., J. Clin. Microbiol. 41:5-14, 2003). Here we show the occurrence of an anomalous diffusion of vancomycin through the VISA cell wall, which is caused by clogging of the cell wall with vancomycin itself. A series of experiments demonstrates that the thickened cell wall of VISA could protect ongoing peptidoglycan biosynthesis in the cytoplasmic membrane from vancomycin inhibition, allowing the cells to continue producing nascent cell wall peptidoglycan and thus making the cells resistant to vancomycin. We conclude that the cooperative effect of the clogging and cell wall thickening enables VISA to prevent vancomycin from reaching its true target in the cytoplasmic membrane, exhibiting a new class of antibiotic resistance in gram-positive pathogens.
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Affiliation(s)
- Longzhu Cui
- Department of Bacteriology, Faculty of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-Ku, Tokyo, 113-8421, Japan.
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9
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Lundstrom TS, Sobel JD. Antibiotics for gram-positive bacterial infections: vancomycin, quinupristin-dalfopristin, linezolid, and daptomycin. Infect Dis Clin North Am 2004; 18:651-68, x. [PMID: 15308280 DOI: 10.1016/j.idc.2004.04.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
An overview of the mechanism of action, dosing, clinical indications, and toxicities of the glycopeptide vancomycin is provided. Emerging gram-positive bacterial resistance to antimicrobials and its mechanisms are reviewed. Strategies to control emergence of resistance are proposed. Newer antimicrobial agents with activity against vancomycin-resistant organisms are now available and play a critical role in the treatment of life-threatening infections.
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Affiliation(s)
- Tammy S Lundstrom
- Division of Infectious Diseases, Wayne State University-Detroit Medical Center, 4201 St. Antoine UHC 2B, Detroit, MI 48201, USA.
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10
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Fukuda M, Hanazome I, Sasaki K. The intraocular dynamics of vancomycin hydrochloride ophthalmic ointment (TN-011) in rabbits. J Infect Chemother 2003; 9:93-6. [PMID: 12673416 DOI: 10.1007/s10156-002-0219-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The intraocular dynamics of 1% vancomycin hydrochloride (VCM) ophthalmic ointment (TN-011) in rabbits was investigated. The animals used in the study were 42 pigmented rabbits with normal eyes (normal group) and 17 pigmented rabbits with Bacillus subtilis-infected eyes (BS group). The infection in the BS group was induced by a method previously established by the authors. Fifty milligrams of a 1% VCM ophthalmic ointment was administered into the cul-de-sacs of the animals' eyes unilaterally in both groups. Serum, bulbar conjunctiva (only from the normal group), cornea, iris-ciliary body, and vitreous were collected 15, 30, 60, 120, and 240 min after the drug administration as samples. Drug concentration was measured by the bioassay method. In the normal group, VCM in the bulbar conjunctiva reached a maximum concentration (98.98 +/- 46.48 microg/g) at 30 min, and decreased to a level below the detection limit at 240 min. The maximum concentration of VCM in the cornea (12.04 +/- 4.73 microg/g) was observed at 30 min. VCM was not detected in the aqueous humour, iris-ciliary body, vitreous, or serum in the normal group at any point. In the BS group, the maximum concentration of VCM was 25.60 +/- 11.01 microg/g in the cornea 15 min after drug administration, and 5.18 +/- 2.60 microg/ml in the aqueous humour at 30 min. VCM in the aqueous humor could be detected (0.37 +/- 0.19 microg/ml) even after 240 min. VCM was not detected in the iris-ciliary body, vitreous, or serum at any point. The intraocular dynamics of 1% VCM ophthalmic ointment (TN-011) revealed that VCM reached the estimated effective concentrations in the aqueous humour as well as extraocular tissues of Bacillus subtilis-infected rabbit eyes.
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Affiliation(s)
- Masamichi Fukuda
- Department of Ophthalmology, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa 920-0293, Japan.
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11
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Haraga I, Nomura S, Fukamachi S, Ohjimi H, Hanaki H, Hiramatsu K, Nagayama A. Emergence of vancomycin resistance during therapy against methicillin-resistant Staphylococcus aureus in a burn patient--importance of low-level resistance to vancomycin. Int J Infect Dis 2002; 6:302-8. [PMID: 12718825 DOI: 10.1016/s1201-9712(02)90165-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVES Staphylococcus aureus with low-level resistance to vancomycin (VLSA) which could develop into vancomycin-resistant S. aureus (VRSA) is most important. However, VLSA is difficult to detect by standard laboratory methods. We describe here improved methods to detect VLSA. METHODS Three methicillin-resistant S. aureus (MRSA) strains, designated Fu6, Fu10, and Fu18, were sequentially isolated from the burn wound site of a patient, during vancomycin therapy. The properties of these strains were compared with those of reference strains Mu3 and Mu50 (previous resistant isolates from other patients). RESULTS The isolated strains, Fu10 and Fu18, had identical phenotypes and genotypes. The vancomycin resistance of Fu10 was equivalent to that of strain Mu3, whereas Fu18 had much higher vancomycin resistance than Fu10 and Mu3, although reaching the level of Mu50. Fu18 showed similar growth to Mu50 on gradient gels and on Mu3 medium. CONCLUSIONS Our data indicate that the VLSA developed vancomycin resistance during exposure to vancomycin in vivo. The population analysis of tested VLSA and vancomycin intermediately resistant S. aureus (VISA) indicates that a penem at relatively low concentrations induced a significant increase in the number of vancomycin-resistant subpopulations. Furthermore, we confirmed that gradient gel analysis and Mu3 medium are simple and useful methods for the detection of VLSA judged as VSSA by its conventional MIC alone.
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Affiliation(s)
- Isao Haraga
- Department of Microbiology, School of Medicine, Fukuoka University, Nanakuma, Jonan-ku, Fukuoka, Japan
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12
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Burnie J, Matthews R, Jiman-Fatami A, Gottardello P, Hodgetts S, D'arcy S. Analysis of 42 cases of septicemia caused by an epidemic strain of methicillin-resistant Staphylococcus aureus: evidence of resistance to vancomycin. Clin Infect Dis 2000; 31:684-9. [PMID: 11017816 DOI: 10.1086/314035] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/1999] [Revised: 02/07/2000] [Indexed: 11/03/2022] Open
Abstract
Recent case reports of vancomycin treatment failures in the United States, Japan, and France have prompted a retrospective analysis of 42 cases of septicemia caused by epidemic methicillin-resistant Staphylococcus aureus strain 15 (EMRSA-15), which is the most prevalent epidemic strain of methicillin-resistant S. aureus in the United Kingdom; all cases occurred in a teaching hospital in Manchester, United Kingdom, between 1994 and 1998. Mortality was lowest (4%) in patients with rifampin-susceptible isolates treated with vancomycin and rifampin. It rose to 38% in patients who were treated with both antibiotics but in whom the organism became resistant to rifampin during therapy, and it reached 78% in patients who had rifampin-resistant isolates or in whom rifampin was contraindicated (P<.0001; Fisher exact test, 2-tailed). All isolates were susceptible to vancomycin by conventional laboratory testing, but susceptibility was lost by growth in vancomycin in vitro, becoming resistant at a minimum inhibitory concentration of 8 mg/L. This was associated with accumulation of cell-wall material. The deoxyribonucleic acid fingerprint remained unchanged. This study suggests that rifampin played a key role in the prevention of deaths caused by an epidemic strain of methicillin-resistant S. aureus that readily gave rise to a subpopulation with reduced susceptibility to vancomycin.
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Affiliation(s)
- J Burnie
- Infectious Diseases Research Unit, University of Manchester, Central Manchester Healthcare Trust, Manchester, United Kingdom.
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Lundstrom TS, Sobel JD. Antibiotics for gram-positive bacterial infections. Vancomycin, teicoplanin, quinupristin/dalfopristin, and linezolid. Infect Dis Clin North Am 2000; 14:463-74. [PMID: 10829266 DOI: 10.1016/s0891-5520(05)70258-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vancomycin is a safe, effective antibiotic for a variety of serious gram-positive infections. Because of emerging resistance in enterococci and staphylococci and the emerging threat of spread of vancomycin-resistant genes to other gram-positive organisms, judicious use of vancomycin should be promoted. Quinupristin/dalfopristin, a streptogramin antibiotic, and linezolid, an oxazolidinone, show promise against some strains of gram-positive bacteria that are resistant to vancomycin.
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Affiliation(s)
- T S Lundstrom
- Department of Medicine, Wayne State University School of Medicine, Detroit, Michigan, USA
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14
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Abstract
Within the past year, infections caused by methicillin-resistant Staphylococcus aureus (MRSA) strains with reduced susceptibility to vancomycin (MIC=8 microg/mL) have been reported in both Japan and the United States. The emergence of these strains poses a potentially serious threat to public health. After 2 such strains (Mu3 and Mu50) were identified at Juntendo Hospital in 1996, a screening program to identify MRSA strains with reduced susceptibility to vancomycin was initiated. Of 970 MRSA strains tested at 195 nonuniversity hospitals throughout Japan, 13 (1.3%) were found to have subpopulations with reduced vancomycin susceptibility (heterogeneous vancomycin resistance). Among 129 MRSA strains identified at 7 university hospitals, 12 (9.3%) demonstrated heterogeneity for vancomycin resistance; 1 of these strains had a vancomycin MIC of 7 microg/mL. Although resistance in these strains is not the result of the transfer of enterococcal vancomycin resistance genes (vanA or vanB), the clonal dissemination of MRSA strains with vancomycin-resistant subpopulations is obviously undesirable. Intensified testing of MRSA strains for resistance to vancomycin and appropriate measures for the prevention of the spread of such strains are recommended.
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Affiliation(s)
- K Hiramatsu
- Department of Bacteriology, Juntendo University, Tokyo, Japan
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Hiramatsu K. Vancomycin resistance in staphylococci. Drug Resist Updat 1998; 1:135-50. [PMID: 16904400 DOI: 10.1016/s1368-7646(98)80029-0] [Citation(s) in RCA: 145] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/1997] [Revised: 02/24/1998] [Accepted: 02/28/1998] [Indexed: 10/25/2022]
Abstract
Recent emergence of vancomycin resistance in methicillin-resistant Staphylococcus aureus (VRSA) has posed a new threat to hospital infection control and antibiotic chemotherapy. Relatively low-level resistance of VRSA compared to that of vancomycin-resistant enterococci (VRE), and prevalence of S. aureus clinical strains heterogeneously resistant to vancomycin (hetero-VRSA), challenge the value of routine antibiotic susceptibility tests as a tool for the prediction of clinical efficacy of vancomycin therapy. This review summarizes the history of emergence of glycopeptide resistance in staphylococci and considers the mechanism of resistance in these organisms.
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Affiliation(s)
- K Hiramatsu
- Department of Bacteriology, Juntendo University, Tokyo, Japan.
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Hiramatsu K, Aritaka N, Hanaki H, Kawasaki S, Hosoda Y, Hori S, Fukuchi Y, Kobayashi I. Dissemination in Japanese hospitals of strains of Staphylococcus aureus heterogeneously resistant to vancomycin. Lancet 1997; 350:1670-3. [PMID: 9400512 DOI: 10.1016/s0140-6736(97)07324-8] [Citation(s) in RCA: 848] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Since the discovery of the vancomycin-resistant Staphylococcus aureus (VRSA) strain Mu50 (minimum inhibitory concentration [MIC] 8 mg/L), there has been concern about the potential spread of such strains throughout Japanese hospitals. Two important questions need to be answered: (1) what is the prevalence of VRSA, and (2) by what mechanism does vancomycin resistance occur. METHODS The vancomycin susceptibilities of three methicillin-resistant S aureus (MRSA) strains (Mu50, Mu3, and H1) and the methicillin-susceptible S aureus type strain FDA209P were compared by MIC determinations and population analysis. Mu3 (MIC 3 mg/L) was isolated from the sputum of a patient with pneumonia after surgery who had failed vancomycin therapy. H1 (MIC 2 mg/L), which is a representative vancomycin-susceptible MRSA strain, was isolated from a patient with pneumonia who responded favourably to vancomycin therapy. Subclones of Mu3 with increased resistance against vancomycin were selected with serial concentrations of vancomycin and their MICs were determined. The prevalence of VRSA and Mu3-like strains in Japanese hospitals was estimated by population analysis from 1149 clinical MRSA isolates obtained from 203 hospitals throughout Japan. The genetic traits of the Mu3 and Mu50 strains were compared with clonotypes of MRSA from around the world. FINDINGS Mu3 and Mu50 had an identical pulsed-field gel electrophoresis banding pattern. When grown in a drug-free medium, Mu3 produced subpopulation of cells with varying degrees of vancomycin resistance, thus demonstrating natural heterogeneity, or variability, in susceptibility to vancomycin. In the presence of vancomycin, Mu3 produced subclones with resistance roughly proportional to the concentrations of vancomycin used. Selection of Mu3 with 8 mg/L or more of vancomycin gave rise to subclones with vancomycin resistance equal to that of Mu50 (MIC 8 mg/L) at a frequency of 1/1,000,000. During screening of Japanese MRSA strains, no strain of VRSA additional to Mu50 was found. The prevalence of MRSA isolates heterogeneously resistant to vancomycin was 20% in Juntendo University Hospital, 9.3% in the other seven university hospitals, and 1.3% in non-university hospitals or clinics. INTERPRETATION Heterogeneously resistant VRSA is a preliminary stage that allows development into VRSA upon exposure to vancomycin. Heterogeneously resistant VRSA was found in hospitals throughout Japan. This finding could explain, at least partly, the frequent therapeutic failure of MRSA infection with vancomycin in Japan.
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Affiliation(s)
- K Hiramatsu
- Department of Bacteriology, Juntendo University, Tokyo, Japan.
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19
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Abstract
Vancomycin is a narrow-spectrum glycopeptide antibiotic with potent antistaphylococcal activity. It is primarily active against gram-positive organisms. Bacterial resistance rarely develops due to its numerous modes of action. The toxic potential of vancomycin is less significant than previously thought. "Red neck syndrome" seems to be the most common side effect and appears to be caused by rapid intravenous infusion. It is characterized by erythema at the base of the neck and the upper back; hypotensive episodes may also occur. Nephrotoxicity and ototoxicity are rare. Relationships between toxicities and serum concentrations have not been established. The disposition of vancomycin after intravenous administration proceeds biphasically--rapid distribution followed by elimination. The drug is excreted primarily unchanged in the urine by glomerular filtration. Vancomycin clearance is reduced and elimination half-life is prolonged in patients with renal insufficiency. Various methods have been published to aid in dosing the drug in these patients. Vancomycin is the drug of choice in the treatment of methicillin-resistant staphylococcal infections. It is also useful in the treatment of gram-positive endocarditis and has been used as alternative therapy in the treatment of prophylaxis of gram-positive infections in penicillin-allergic patients. Oral vancomycin is the preferred therapy in antibiotic-associated colitis.
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Brown N, Ho DH, Fong KL, Bogerd L, Maksymiuk A, Bolivar R, Fainstein V, Bodey GP. Effects of hepatic function on vancomycin clinical pharmacology. Antimicrob Agents Chemother 1983; 23:603-9. [PMID: 6859839 PMCID: PMC184709 DOI: 10.1128/aac.23.4.603] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Using a recently developed radioimmunoassay, we performed 15 vancomycin pharmacology studies in cancer patients with infections. Vancomycin (500 mg) was infused intravenously for 30 min every 6 h for up to 7 days. The plasma disappearance curve was biphasic, with an initial half-life of less than 30 min. The second half-life (t1/2 beta), not dose related, varied from 1.4 to 231 h among the patients. In six studies of patients with normal hepatic functions, the t1/2 beta was 2.6 h; the rate of total clearance was 162 ml/min. In contrast, nine studies of patients with impaired liver function had a much longer t1/2 beta (37 h) and a decrease in the rate of total clearance to 48 ml/min. These factors resulted in an increase in the value of area under the concentration-time curve from 59 to 3,434 micrograms X h/ml. These results have demonstrated the importance of the effects of liver function on vancomycin disposition. The vancomycin dose and schedule should be adjusted for patients with liver impairment.
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Abstract
While vancomycin is thus not as nephrotoxic as once feared, its use by the parenteral route should be avoided if possible when other nephrotoxic drugs are being given. Used properly, vancomycin appears efficacious and can be given with safety to infants, children, and adults. Vancomycin is incompatible with many other drugs in intravenous solutions, especially chloramphenicol, adrenocorticosteroids, and methicillin.
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Fong KL, Ho DH, Bogerd L, Pan T, Brown NS, Gentry L, Bodey GP. Sensitive radioimmunoassay for vancomycin. Antimicrob Agents Chemother 1981; 19:139-43. [PMID: 7247352 PMCID: PMC181372 DOI: 10.1128/aac.19.1.139] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
A radioimmunoassay for vancomycin has been developed which uses rabbit antiserum induced by vancomycin-bovine serum albumin conjugates and vancomycin labeled with 3H or 125I. Using either isotope, the method is simple and reproducible and has a sensitivity of 4 or 0.04 ng/ml, depending on the tracer used. This is 200- to 20,000-fold improvement in sensitivity compared with the most sensitive bioassay. Drug levels in serum or urine samples from patients receiving vancomycin can be determined by this assay procedure without processing. The data obtained with 3H and 125I labels were in good agreement. Patients' plasma vancomycin concentrations determined by radioimmunoassay correlated well with those determined by bioassay when the drug was administered intravenously. However, after oral administration the drug could be detected only by radioimmunoassay. The antiserum was evaluated for cross-reactivity with a wide variety of antibiotics and cancer chemotherapeutic agents, and no significant interference was found.
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