Crystal structure of a short peptide L-Lys-D-Ala-D-Ala (bacterial cell wall precursor, in green) bound to vancomycin (blue) through hydrogen bonds. Reported by Knox and Pratt in Antimicrob. Agents. Chemother., 1990 1342-1347

Vancomycin (INN) (IPA: [ˌvæŋkoˈmaɪsən]) is a glycopeptide antibiotic used in the prophylaxis and treatment of infections caused by Gram-positive bacteria. It has traditionally been reserved as a drug of "last resort", used only after treatment with other antibiotics had failed, although the emergence of vancomycin-resistant organisms means that it is increasingly being displaced from this role by linezolid and the carbapenems. In pharmacology and toxicology, a route of administration is the path by which a drug, fluid, poison or other substance is brought into contact with the body 1. ... An intravenous drip in a hospital Intravenous therapy or IV therapy is the administration of liquid substances directly into a vein. ... Image File history File linksMetadata Size of this preview: 675 × 600 pixelsFull resolution (810 × 720 pixel, file size: 215 KB, MIME type: image/jpeg) This is a picture generated from crystal structure data reported by James R. Knox and R. F. Pratt in Antimicrobial Agents and Chemotherapy, Year 1990, Volume... Image File history File linksMetadata Size of this preview: 675 × 600 pixelsFull resolution (810 × 720 pixel, file size: 215 KB, MIME type: image/jpeg) This is a picture generated from crystal structure data reported by James R. Knox and R. F. Pratt in Antimicrobial Agents and Chemotherapy, Year 1990, Volume... An International Nonproprietary Name (INN) is the official non-proprietary or generic name given to a pharmaceutical substance, as designated by the World Health Organization. ... Articles with similar titles include the NATO phonetic alphabet, which has also informally been called the “International Phonetic Alphabet”. For information on how to read IPA transcriptions of English words, see IPA chart for English. ... This page may meet Wikipedias criteria for speedy deletion. ... Staphylococcus aureus - Antibiotics test plate. ... Prophylaxis refers to any medical or public health procedure whose purpose is to prevent, rather than treat or cure, disease. ... Gram-positive bacteria are those that are stained dark blue or violet by gram staining, in contrast to gram-negative bacteria, which are not affected by the stain. ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... Drugs of last resort are drugs with the most potent antibiotic, antiviral, or anticancer effect, and for which no (or for cancer, very few) resistant strains are known. ... Linezolid is a synthetic systemic antibiotic drug. ... Carbapenems are a class of beta-lactam antibiotics. ...

History

Vancomycin was first isolated by EC Kornfeld (working at Eli Lilly) from a soil sample collected from the interior jungles of Borneo by a missionary. The organism that produced it was eventually named Streptomyces orientalis. The original indication for vancomycin was for the treatment of penicillin-resistant Staphylococcus aureus.^[1][2] Eli Lilly and Company (NYSE: LLY) is a global pharmaceutical company and one of the worlds largest corporations. ... Borneo is the third largest island in the world. ... Penicillin nucleus Penicillin (sometimes abbreviated PCN) refers to a group of β-lactam antibiotics used in the treatment of bacterial infections caused by susceptible, usually Gram-positive, organisms. ... Binomial name Staphylococcus aureus Rosenbach 1884 Staphylococcus aureus, the most common cause of staph infections, is a spherical bacterium, frequently living on the skin or in the nose of a healthy person, that can cause a range of illnesses from minor skin infections (such as pimples, boils, and cellulitis) and...

The compound was initially labelled compound 05865, but was eventually given the generic name, vancomycin (derived from the word "vanquished"). One advantage that was quickly apparent was that staphylococci did not develop significant resistance despite serial passage in culture media containing vancomycin. The rapid development of penicillin-resistance by staphylococci led to the compound being fast-tracked for approval by the FDA in 1958. Eli Lilly first marketed vancomycin hydrochloride under the trade name Vancocin.^[1] Penicillin nucleus Penicillin (sometimes abbreviated PCN) refers to a group of β-lactam antibiotics used in the treatment of bacterial infections caused by susceptible, usually Gram-positive, organisms. ... FDA logo The Food and Drug Administration (FDA) is an agency of the United States Department of Health and Human Services and is responsible for regulating food, dietary supplements, drugs, biological medical products, blood products, medical devices, radiation-emitting devices, veterinary products, and cosmetics in the United States. ... Year 1958 (MCMLVIII) was a common year starting on Wednesday of the Gregorian calendar. ...

Vancomycin never became first line treatment for Staphylococcus aureus for several reasons:

1. The drug must be given intravenously, because it is not absorbed orally.
2. β-lactamase-resistant semi-synthetic penicillins such as methicillin (and its successors, nafcillin and cloxacillin) were subsequently developed.
3. Early trials using early impure forms of vancomycin ("Mississippi mud") which were found to be toxic to the ears and to the kidneys;^[3] these findings led to vancomycin being relegated to the position of a drug of last resort.

In 2004, Eli Lilly licensed Vancocin to ViroPharma in the U.S., Flynn Pharma in the UK and Aspen Pharmacare in Australia. The patent expired in the early 1980s and generic versions of the drug are also available under various trade names. An intravenous drip in a hospital Intravenous therapy or IV therapy is the administration of liquid substances directly into a vein. ... Methicillin (USAN) or meticillin (INN, BAN) is a narrow spectrum beta-lactam antibiotic. ... Nafcillin sodium is an beta-lactam antibiotic related to penicillin. ... Cloxacillin is a semisynthetic antibiotic in the same class as penicillin. ... Eli Lilly and Company (NYSE: LLY) is a global pharmaceutical company and one of the worlds largest corporations. ... ViroPharma Incorporated, a pharmaceutical company, develops and sells drugs that address serious diseases treated by physician specialists and in hospital settings. ... A patent is a set of exclusive rights granted by a state to a patentee (the inventor or assignee) for a fixed period of time in exchange for the regulated, public disclosure of certain details of a device, method, process or composition of matter (substance) (known as an invention) which... The 1980s refers to the years from 1980 to 1989. ...

Pharmacology and chemistry

It is a branched tricyclic glycosylated nonribosomal peptide produced by the fermentation of the Actinobacteria species Amycolatopsis orientalis (formerly designated Nocardia orientalis). Glycosylation is the process or result of addition of saccharides to proteins and lipids. ... Nonribosomal peptides (NRP) are a class of secondary metabolites, usually produced by microorganisms like bacteria and fungi. ... This article or section does not cite any references or sources. ... Subclasses Acidimicrobidae Actinobacteridae Coriobacteridae Rubrobacteridae Sphaerobacteridae The Actinobacteria or Actinomycetes are a group of Gram-positive bacteria. ... Amycolatopsis is a genus of high-GC content bacteria within the family Pseudonocardiaceae [1]. ^ NCBI Taxonomy Browser, http://www. ...

Vancomycin acts by inhibiting proper cell wall synthesis in Gram-positive bacteria. The mechanism inhibited, and various factors related to entering the outer membrane of Gram-negative organisms mean that vancomycin is not active against Gram-negative bacteria (except some non-gonococcal species of Neisseria). A cell wall is a fairly rigid layer surrounding a cell, located external to the cell membrane, that provides the cell with structural support, protection, and a filtering mechanism. ... Bacteria that are Gram-negative are not stained dark blue or violet by Gram staining, in contrast to Gram-positive bacteria. ... Neisseria is a genus of bacteria, included among the proteobacteria, a large group of gram-negative forms. ...

Specifically, vancomycin prevents incorporation of N-acetylmuramic acid (NAM)- and N-acetylglucosamine (NAG)-peptide subunits into the peptidoglycan matrix; which forms the major structural component of Gram-positive cell walls. Peptidoglycan, also known as murein, is a polymer consisting of sugars and amino acids that forms a homogeneous layer outside the plasma membrane of eubacteria. ...

The large hydrophilic molecule is able to form hydrogen bond interactions with the terminal D-alanyl-D-alanine moieties of the NAM/NAG-peptides. Normally this is a five-point interaction. This binding of vancomycin to the D-Ala-D-Ala prevents the incorporation of the NAM/NAG-peptide subunits into the peptidoglycan matrix. The adjective hydrophilic describes something that likes water (from Greek hydros = water; philos = friend). ... An example of a quadruple hydrogen bond between a self-assembled dimer complex reported by Meijer and coworkers. ...

Vancomycin exhibits atropisomerism — it has two chemically distinct rotamers owing to the rotational restriction of the chlorotyrosine residue (on the right hand side of the figure). The form present in the drug is the thermodynamically more stable conformer, and, importantly, has more potent activity. Atropisomers are stereoisomers resulting from hindered rotation about single bonds where the steric strain barrier to rotation is high enough to allow for the isolation of the conformers. ... In chemistry, a chemical conformation is the spatial arrangement of atoms in a molecule. ... Conformational isomerism is the phenomenon of molecules with the same structural formula but different conformations (conformers) of atoms about a rotating bond. ...

Clinical use

Indications

Vancomycin is indicated for the treatment of serious, life-threatening infections by Gram-positive bacteria which are unresponsive to other less toxic antibiotics. Gram-positive bacteria are those that are stained dark blue or violet by gram staining, in contrast to gram-negative bacteria, which are not affected by the stain. ...

The increasing emergence of vancomycin-resistant enterococci has resulted in the development of guidelines for use by the Centers for Disease Control (CDC) Hospital Infection Control Practices Advisory Committee. These guidelines restrict use of vancomycin to the following indications:^[4] Species E. faecalis etc. ... The Centers for Disease Control and Prevention (CDC) in Atlanta is recognized as the lead United States agency for protecting the public health and safety of people by providing credible information to enhance health decisions, and promoting health through strong partnerships with state health departments and other organizations. ...

• treatment of serious infections caused by susceptible organisms resistant to penicillins (methicillin-resistant Staphylococcus aureus and multi-resistant Staphylococcus epidermidis (MRSE)) or in individuals with serious allergy to penicillins
• pseudomembranous colitis (relapse or unresponsive to metronidazole treatment)
• For treatment of infections caused by gram-positive microorganisms in patients who have serious allergies to beta-lactam antimicrobials. (http://wonder.cdc.gov/wonder/prevguid/m0039349/m0039349.asp)
• antibacterial prophylaxis for endocarditis following certain procedures in penicillin-hypersensitive individuals at high risk
• surgical prophylaxis for major procedures involving implantation of prostheses in institutions with a high rate of MRSA or MRSE

Penicillin nucleus Penicillin (sometimes abbreviated PCN) refers to a group of β-lactam antibiotics used in the treatment of bacterial infections caused by susceptible, usually Gram-positive, organisms. ... Binomial name Staphylococcus aureus Rosenbach 1884 Methicillin-resistant Staphylococcus aureus (MRSA) is a specific strain of the Staphylococcus aureus bacterium that has developed antibiotic resistance to all penicillins, including methicillin and other narrow-spectrum β-lactamase-resistant penicillin antibiotics. ... Binomial name Staphylococcus epidermidis (Winslow & Winslow 1908) Evans 1916 Staphylococcus epidermidis is a member of the bacterial genus Staphylococcus, consisting of Gram-positive cocci arranged in clusters. ... Penicillin nucleus Penicillin (sometimes abbreviated PCN) refers to a group of β-lactam antibiotics used in the treatment of bacterial infections caused by susceptible, usually Gram-positive, organisms. ... Pseudomembranous colitis is an infection of the colon often, but not always, caused by the bacterium Clostridium difficile. ... Metronidazole (INN) (IPA: ) is a nitroimidazole antibiotic drug used in the treatment of infections caused by susceptible organisms particularly anaerobic bacteria and protozoa. ... Endocarditis is an inflammation of the inner layer of the heart, the endocardium. ... Hypersensitivity refers to undesirable (damaging, discomfort-producing and sometimes fatal) reactions produced by the normal immune system. ... A United States Army soldier plays foosball with two prosthetic arms Jon Comer, professional skateboarder with a prosthetic leg. ...

Adverse effects

Common adverse drug reactions (≥1% of patients) associated with IV vancomycin include: local pain, which may be severe and/or thrombophlebitis. An adverse drug reaction (abbreviated ADR) is a term to describe the unwanted, negative consequences sometimes associated with the use of medications. ... It has been suggested that this article or section be merged into deep vein thrombosis. ...

Damage to the kidneys and to the hearing were a side effect of the early impure versions of vancomycin, and these were prominent in the clinical trials conducted in the mid-1950s. Later trials using purer forms of vancomycin found that nephrotoxicity is an infrequent adverse effect (0.1–1% of patients), but that this is accentuated in the presence of aminoglycosides.^[5] Nephrotoxicity is a poisonous effect of some substances, both toxins and medication, on the kidney. ... Aminoglycosides are a group of antibiotics that are effective against certain types of bacteria. ...

Rare adverse effects (<0.1% of patients) include: anaphylaxis, toxic epidermal necrolysis, erythema multiforme, red man syndrome (see below), superinfection, thrombocytopenia, neutropenia, leucopenia, tinnitus, dizziness and/or ototoxicity (see below).^[4] }} In medicine, anaphylaxis is a severe and rapid multi-system allergic reaction. ... Toxic epidermal necrolysis is a life-threatening and usually drug-induced dermatological condition that occurs more often in women than in men. ... Stevens-Johnson syndrome (SJS) is a severe and potentially life-threatening (15% of cases) disease, it is a hypersensitivity complex affecting the skin and the mucous membranes, a severe expression of erythema multiforme (EM) (and so SJS is also called erythema multiforme major). ... Crystal structure of a short peptide L-Lys-D-Ala-D-Ala (bacterial cell wall precursor, in green) bound to vancomycin (blue) through hydrogen bonds. ... In virology, superinfection describes the process by which a cell that has previously been infected by one virus gets coinfected with another virus at a later point in time. ... Thrombocytopenia (or -paenia, or thrombopenia in short) is the presence of relatively few platelets in blood. ... Neutropenia (or neutropaenia, adjective neutrop(a)enic) is a hematological disorder characterized by an abnormally low number of neutrophil granulocytes (a type of white blood cell). ... Leukopenia or leukocytopenia refers to a decrease in the number of circulating white blood cells (leukocytes) in the blood. ... Tinnitus (IPA pronunciation: or ,[1] from the Latin word for ringing[2]) is the perception of sound in the human ear in the absence of corresponding external sound(s). ... Crystal structure of a short peptide L-Lys-D-Ala-D-Ala (bacterial cell wall precursor, in green) bound to vancomycin (blue) through hydrogen bonds. ...

Lately it has been emphasized that vancomycin can induce platelet-reactive antibodies in the patient, leading to severe thrombocytopenia and bleeding with florid petechial hemorrhages, ecchymoses, and wet purpura. ^[6] Thrombocytopenia (or -paenia, or thrombopenia in short) is the presence of relatively few platelets in blood. ... A bruise or contusion or ecchymoses is a kind of injury, usually caused by blunt impact, in which the capillaries are damaged, allowing blood to seep into the surrounding tissue. ...

Dosing considerations

Intravenous vs oral administration

Vancomycin needs to be given intravenously (IV) for systemic therapy since it does not cross through the intestinal lining. It is a large hydrophilic molecule which partitions poorly across the gastrointestinal mucosa. The only indication for oral vancomycin therapy is in the treatment of pseudomembranous colitis, where it must be given orally to reach the site of infection in the colon. Inhaled vancomycin has also been used (off-label), via nebulizer, for treatment of various infections of the upper and lower respiratory tract. An intravenous drip in a hospital Intravenous therapy or IV therapy is the administration of liquid substances directly into a vein. ... The mucous membranes (or mucosa) are linings of ectodermic origin, covered in epithelium, that line various body cavities and internal organs. ... Pseudomembranous colitis is an infection of the colon often, but not always, caused by the bacterium Clostridium difficile. ... The term off-label refers to the use of a drug for a medical condition other than for which it was officially approved and marketed. ... A nebulizer with an attached inhaling apparatus In medicine, a nebulizer is a device used to administer medication to people in forms of a liquid mist to the airways. ...

Red man syndrome

Vancomycin must be administered in a dilute solution slowly, over at least 60 minutes (maximum rate of 10 mg/minute for doses >500 mg).^[4] This is due to the high incidence of pain and thrombophlebitis and to avoid an infusion reaction known as the red man syndrome or red neck syndrome. This syndrome, usually appearing within 4–10 minutes after the commencement or soon after the completion of an infusion, is characterised by flushing and/or and an erythematous rash that affects the face, neck and upper torso. Less frequently, hypotension and angioedema may also occur. Symptoms may be treated with antihistamines, including diphenhydramine.^[7] Hurting redirects here. ... It has been suggested that this article or section be merged into deep vein thrombosis. ... Erythema is an abnormal redness of the skin caused by capillary congestion. ... In physiology and medicine, hypotension refers to an abnormally low blood pressure. ... Angioedema (BE: angiooedema), also known by its eponym Quinckes edema, is the rapid swelling (edema) of the skin, mucosa and submucosal tissues. ... An antihistamine is a drug which serves to reduce or eliminate effects mediated by histamine, an endogenous chemical mediator released during allergic reactions, through action at the histamine receptor. ... Diphenhydramine hydrochloride (trade name Benadryl, as produced by Pfizer, or Dimedrol outside the U.S.) is an over-the-counter (OTC) antihistamine and sedative. ...

Therapeutic drug monitoring

Vancomycin activity is considered to be time-dependent – that is, antimicrobial activity depends on the duration that the drug level exceeds the minimum inhibitory concentration (MIC) of the target organism. Thus, peak levels have not been shown to correlate with efficacy or toxicity – indeed concentration monitoring is unnecessary in most cases. Circumstances where therapeutic drug monitoring (TDM) is warranted include: patients receiving concomitant aminoglycoside therapy, patients with (potentially) altered pharmacokinetic parameters, patients on haemodialysis, during high dose or prolonged treatment, and patients with impaired renal function. In such cases, trough concentrations are measured.^{[4][8][9][10]} Minimum inhibitory concentration (MIC), in microbiology, is the lowest concentration of an antimicrobial that will inhibit the visible growth of a microorganism after overnight incubation. ... Therapeutic drug monitoring is a branch of clinical chemistry that specialises in the measurement of medication levels in blood. ... Pharmacokinetics (in Greek: pharmacon meaning drug, and kinetikos meaning putting in motion) is a branch of pharmacology dedicated to the determination of the fate of substances administered externally to a living organism. ... It has been suggested that Artificial kidney be merged into this article or section. ...

Toxicity

Vancomycin has traditionally been considered a nephrotoxic and ototoxic drug, based on observations by early investigators of elevated serum levels in renally impaired patients who had experienced ototoxicity, and subsequently through case reports in the medical literature. However, as the use of vancomycin increased with the spread of MRSA beginning in the seventies, it was recognised that the previously reported rates of toxicity were not being observed. This was attributed to the removal of the impurities present in the earlier formulation of the drug, although those impurities were not specifically tested for toxicity.^[2] Nephrotoxicity is a poisonous effect of some substances, both toxins and medication, on the kidney. ... Ototoxicity is damage of the ear (oto), specifically the cochlea or auditory nerve and sometimes the vestibulum, by a toxin (often medication). ... MRSA, or methicillin-resistant Staphylococcus aureus, is a bacterium that has developed antibiotic resistance, first to penicillin in 1947, and later to methicillin. ...

Nephrotoxicity

Subsequent reviews of accumulated case reports of vancomycin-related nephrotoxicity found that many of the patients had also received other known nephrotoxins, particularly aminoglycosides. Most of the rest had other confounding factors, or insufficient data regarding the possibility of such, that prohibited the clear association of vancomycin with the observed renal dysfunction. Aminoglycosides are a group of antibiotics that are effective against certain types of bacteria. ...

In 1994, Cantu and colleagues found that the use of vancomycin monotherapy was clearly documented in only three of 82 available cases in the literature.^[8] Prospective and retrospective studies attempting to evaluate the incidence of vancomycin-related nephrotoxicity have largely been methodologically flawed and have produced variable results. The most methodologically sound investigations indicate that the actual incidence of vancomycin-induced nephrotoxicity is around 5–7%. To put this into context, similar rates of renal dysfunction have been reported for cefamandole and benzylpenicillin, two reputedly non-nephrotoxic antibiotics. Penicillin nucleus Penicillin refers to a group of β-lactam antibiotics used in the treatment of bacterial infections caused by susceptible, usually Gram-positive, organisms. ...

Additionally, evidence to relate nephrotoxicity to vancomycin serum levels is inconsistent. Some studies have indicated an increased rate of nephrotoxicity when trough levels exceed 10 µg/mL, but others have not reproduced these results. Nephrotoxicity has also been observed with concentrations within the "therapeutic" range as well. Essentially, the reputation of vancomycin as a nephrotoxin is over-stated, and it has not been demonstrated that maintaining vancomycin serum levels within certain ranges will prevent its nephrotoxic effects, when they do occur.

Ototoxicity

Attempts to establish rates of vancomycin-induced ototoxicity are even more difficult due to the scarcity of quality evidence. The current consensus is that clearly related cases of vancomycin ototoxicity are rare. The association between vancomycin serum levels and ototoxicity is also uncertain. While cases of ototoxicity have been reported in patients whose vancomycin serum level exceeded 80 µg/mL, cases have been reported in patients with therapeutic levels as well. Thus, it also remains unproven that therapeutic drug monitoring of vancomycin for the purpose of maintaining "therapeutic" levels will prevent ototoxicity. Therapeutic drug monitoring is a branch of clinical chemistry that specialises in the measurement of medication levels in blood. ...

Interactions with other nephrotoxins

Another area of controversy and uncertainty concerns the question of whether, and if so, to what extent, vancomycin increases the toxicity of other nephrotoxins. Clinical studies have yielded variable results, but animal models indicate that there probably is some increased nephrotoxic effect when vancomycin is added to nephrotoxins such as aminoglycosides. However, a dose- or serum level-effect relationship has not been established.

Antibiotic resistance

Intrinsic resistance

There are a few gram-positive bacteria that are intrinsically resistant to vancomycin: these are Leuconostoc and Pediococcus species, but these organisms are rare causes of disease in humans.^[11] Most Lactobacillus species are also intrinsically resistant to vancomycin^[11] (the exception is L. acidophilus^[12]). Gram-positive bacteria are those that are stained dark blue or violet by gram staining, in contrast to gram-negative bacteria, which are not affected by the stain. ... Leuconostoc is a kind of bacteria, often found in butter. ... Pediococcus is a genus of bacteria. ... Species L. acidophilus L. brevis L. delbrueckii subsp. ... Binomial name Lactobacillus acidophilus (Moro 1900) Hansen & Mocquot 1970 Lactobacillus acidophilus is one of several bacteria in the genus Lactobacillus. ...

Most gram-negative bacteria are intrinsically resistant to vancomycin because of their outer membrane is impermeable to large glycopeptide molecules^[13] (with the exception of some non-gonococcal Neisseria species).^[14] Bacteria that are Gram-negative are not stained dark blue or violet by Gram staining, in contrast to Gram-positive bacteria. ... Neisseria is a genus of bacteria, included among the proteobacteria, a large group of gram-negative forms. ...

Acquired resistance

Acquired microbial resistance to vancomycin is a growing problem, particularly within health care facilities such as hospitals. With vancomycin being the last-line antibiotic for serious Gram-positive infections there is the growing prospect that resistance will result in a return to the days when fatal bacterial infections were common. Vancomycin-resistant enterococci (VRE) emerged in 1987. Vancomycin resistance emerged in more common pathogenic organisms during the 1990s and 2000s, including vancomycin-intermediate Staphylococcus aureus (VISA), vancomycin-resistant Staphylococcus aureus (VRSA), and vancomycin-resistant Clostridium difficile.^[15][16] There is some suspicion that agricultural use of avoparcin, another similar glycopeptide antibiotic, has contributed to the emergence of vancomycin-resistant organisms. Antibiotic resistance is the ability of a micro-organism to withstand the effects of an antibiotic. ... Gram-positive bacteria are those that are stained dark blue or violet by gram staining, in contrast to gram-negative bacteria, which are not affected by the stain. ... 1987 (MCMLXXXVII) was a common year starting on Thursday of the Gregorian calendar. ... For the band, see 1990s (band). ... The 2000s are the current decade, spanning from 2000 to 2009. ... Vancomycin-resistant Staphylococcus aureus (VRSA) is a strain of Staphylococcus aureus that has become resistant to the glycopeptide antibiotic vancomycin. ... Vancomycin-resistant Staphylococcus aureus (VRSA) is a strain of Staphylococcus aureus that has become resistant to the glycopeptide antibiotic vancomycin. ... Binomial name Clostridium difficile Hall & OToole, 1935 Clostridium difficile or CDF/cdf (Template:Audo, alternatively ) (also referred to as C. diff or C-diff) is a species of bacteria of the genus Clostridium which are gram-positive, anaerobic, spore-forming rods (bacillus). ...

One mechanism of resistance to vancomycin appears to be alteration to the terminal amino acid residues of the NAM/NAG-peptide subunits, normally D-alanyl-D-alanine, which vancomycin binds to. Variations such as D-alanyl-D-lactate and D-alanyl-D-serine result in only a 4-point hydrogen bonding interaction being possible between vancomycin and the peptide. This loss of just one point of interaction results in a 1000-fold decrease in affinity. Phenylalanine is one of the standard amino acids. ...

In Enterococci this modification appears to be due to the expression of an enzyme which alters the terminal residue. Three main resistance variants have been characterised to date among resistant Enterococcus faecium and E. faecalis populations.

• VanA - resistance to vancomycin and teicoplanin, inducible on exposure to these agents
• VanB - lower level resistance, inducible by vancomycin but strains may remain susceptible to teicoplanin
• VanC - least clinically important, resistance only to vancomycin, constitutive resistance

The development and use of novel antibiotics such as linezolid and daptomycin is expected to delay, but not halt, the emergence of bacteria resistant to all available antibiotics. Teicoplanin is an antibiotic used in the prophylaxis and treatment of serious infections caused by Gram-positive bacteria. ... Linezolid is a synthetic systemic antibiotic drug. ... Daptomycin is a novel lipopeptide antibiotic used in the treatment of certain infections caused by Gram-positive organisms. ...

References

The Australian Medicines Handbook or AMH is a medical reference text commonly used in practice by health professionals (particularly general practitioners and pharmacists) in Australia. ... The New England Journal of Medicine (NEJM) is a peer-reviewed medical journal published by the Massachusetts Medical Society with the highest impact factor for a general medical journal. ...

See also

• Antibiotic resistance
• Methicillin-resistant Staphylococcus aureus
• Vancomycin-resistant Staphylococcus aureus

Antibiotic resistance is the ability of a micro-organism to withstand the effects of an antibiotic. ... Binomial name Staphylococcus aureus Rosenbach 1884 Methicillin-resistant Staphylococcus aureus (MRSA) is a specific strain of the Staphylococcus aureus bacterium that has developed antibiotic resistance to all penicillins, including methicillin and other narrow-spectrum β-lactamase-resistant penicillin antibiotics. ... Vancomycin-resistant Staphylococcus aureus (VRSA) is a strain of Staphylococcus aureus that has become resistant to the glycopeptide antibiotic vancomycin. ...

External links

• Vancomycin information – created by Princeton University students
• Vancomycin information site and forum