Basic Review – Vancomycin
GlobalRPh Student writer
Vancomycin is a drug that is beneficial in the case of life-threatening bacterial infections and should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. Common administration routes: intravenously, orally or by inhalation. The bactericidal action results primarily from inhibition of cell-wall biosynthesis. In addition, vancomycin alters bacterial-cell-membrane permeability and RNA synthesis.
Edmund Kornfeld was the first person to isolate Vancomycin in the year 1953 from the soil sample of Borneo. It is made using the soil bacterium Amycolatopsisorientalis. The initial name under which Vancomycin Hydrochloride was marketed by Eli Lilly was Vancocin. It came into the market in the year 1954. The World Health Organization has categorized it as the health system’s most effective and safe medicines.
Therapeutic monitoring:
Vancomycin has biexponential distribution and moderate hydrophilicity. Nephrotoxicity and ototoxicity: Monitor renal function in all patients, especially patients with underlying renal impairment, patients with co-morbidities that predispose to renal impairment, and patients receiving concomitant therapy with a drug known to be nephrotoxic. This necessitates plasma level monitoring. It is applicable in the case of patients on hemodialysis, those with altered pharmacokinetic parameters, reduced renal function.
Uses of Vancomycin:
Vancomycin has the following medical uses:
1. Treatment of serious infections in the skin.
2. Endocarditis treatment in case of the patients who are hypersensitive to penicillin
3. Infections in the bone and joints
4. For treating Methicillin-resistant Staphylococcus Aureus(MSRA) induced meningitis.
5. Infections in the bloodstream
6. Treatment of Clostridium Difficile induced Colitis through the oral dosage when Metronidazole treatment doesn’t work.
7. To a certain extent, Vancomycin stops the progression of primary sclerosing cholangitis as well as prevents its symptoms. But the complete cure is not possible with it.
8. For prevention of endophthalmitis through intravitreal injection for gram-positive bacteria coverage. This is known to have certain side effects.
9. Treatment of persons who are allergic to beta-lactam antimicrobials, suffering from Gram-positive microorganism- induced infections.
Vancomycin is the only treatment in the case of sepsis and infection in the lower respiratory tract occurring because of the same bacteria.
Side effects of this drug:
Here are the common side effects of this antibiotic:
1.Pain in the injected area along with allergic reactions and thrombophlebitis.
2. Hearing loss.
3. Hypotension
4. Bone marrow suppression
Other side effects include:
1. Possible nephrotoxicity (several factors can impact the probability).
2. Anaphylaxis
3. Toxic epidermal necrolysis
4. Erythema multiforme
5. Redman syndrome
6. Superinfection
7. The occurrence of bleeding with florid petechial hemorrhages
8. Neutropenia
9. Leukopenia
10. Tinnitus
11. Dizziness
12. Ototoxicity
13. DRESS syndrome
14. Chances of platelet-reactive antibodies formation that causes severe thrombocytopenia
15.Ecchymoses
16. Wet Purpura
Resistance to the antibiotic:
There are certain cases of intrinsic resistance to this antibiotic, which are as follows:
1. Leuconostoc and Pediococcus species are the gram-positive bacteria which have intrinsic resistance towards this drug but they rarely cause diseases in humans.
2. Most of the Lactobacillus species except L. acidophilus and L. Delbruekii.
3. Other gram-positive bacteria which are resistant to it are Erysipelothrixrhusiopathiae, Weissellaconfusa, and Clostridium Innocuum
4. Most of the Gram-negative bacteria are intrinsically resistant to it since their outer membranes do not allow the large glycopeptide molecules
Acquired resistance:
In the hospitals, we can find increasing cases of the microbial resistance to this antibiotic. Linezolid and Daptomycin are new alternatives to this drug. But since Vancomycin has widely prevalent uses it becomes a concern when resistance to it develops. This is quite worrisome for those patients when the identification of resistant infections is not possible soon because of which the unproductive treatment continues.
In the year 1987, the emergence of Vancomycin-resistant Enterococcus occurred. Then its resistance emerged in the common pathogenic organisms such as Vancomycin-intermediate S. aureus (VISA) and Vancomycin-resistant S. aureus (VRSA), during the 1990s and 2000s. Another important cause of vancomycin-resistant organisms’ evolution is the agricultural use of Avoparcin or similar glycopeptide antibiotics.
Among the Enterococcus Faecium and E. Faecalis which are resistant to Vancomycin, there are 3 kinds of resistant variants, namely:
1. Van A – Enterococcal resistance occurs when exposed to Vancomycin and Teicoplanin.
2. Van B – Vancomycin induces a low-level enterococcal resistance, though the strains are susceptive to Teicoplanin.
3. Van C – It is only resistant to Vancomycin and constitutive resistance.
Reasons for not using Vancomycin as the first-line treatment for S.Aureus:
1. Its oral bioavailability is low as its intravenous injections are available for treating infections.
2. The development of methicillin, which is β-Lactamase-resistant semisynthetic penicillin, was found to be more effective against non-MRSA Staphylococci.
