Methicillin vancomycin

Staphylococcus epidennidis and S aureus are common pathogens associated with infection originating from intravenous lines. Most strains of these organisms responsible for hospital-acquired infections are resistant to methicillin. Vancomycin remains the drug of choice for both MRSA and MRSE. Quinupristin-dalfopristin is usually effective in the case of staphylococci resistant to vancomycin. 

As recently as 1970, only about 30 naturally occurring organohalogen compounds were known. It was simply assumed that chloroform, halogenated phenols, chlorinated aromatic compounds called PCBs, and other such substances found in the environment were industrial pollutants. Now, only a third of a century later, the situation js quite different. More than 5000 organohalogen compounds have been found to occur naturally, and tens of thousands more surely exist. From a simple compound like chloromethane to an extremely complex one like vancomycin, a remarkably diverse range of organohalogen compounds exists in plants, bacteria, and animals. Many even have valuable physiological activity. Vancomycin, for instance, is a powerful antibiotic produced by the bacterium Amycolatopsis orientalis and used clinically to treat methicillin-resistant Staphylococcus aureus (MRSA). 

Problems of recent years involving listeriosis, salmonellosis, giardiasis and Legionnaire s disease have received attention, as have the re-emergence of tuberculosis and the importance of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). 

Gaspar-Marques,C. Rijo,P. Sim5es, M. F. Duarte,M. A. Rodriguez, B. Abietanesfrom Plectranthus grandidentatus and P. hereroensis against methicillin- and vancomycin-resistant bacteria. Phytomedicine 2006, 13, 267-271. 

Inpatient treatment of methicillin-resistant S. aureus can consist of IV vancomycin or oral agents as described above, depending on the severity of infection and concomitant organisms. IV vancomycin may also be converted to oral step-down therapy upon discharge. 

Infections acquired from an external source are referred to as exogenous infections. These infections may occur as a result of human-to-human transmission, contact with exogenous bacterial populations in the environment, and animal contact. Resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus spp. 

It is important to determine (1) whether the isolate is methicillin-susceptible or methicillin-resistant and (2) whether the patient has a prosthetic valve. For patients with no prosthetic material, methicillin-susceptible staphylococci treatment should consist of a penicillinase-resistant penicillin (e.g., nafcillin or oxacillin) with or without gentamicin, and for methicillin-resistant strains, therapy should consist of vancomycin (see Table 71-4). Combination therapy with aminoglycosides, when used in these patients, typically is given only during the first 3 to 5 days of therapy. In the absence of prosthetic material, some treatment guidelines do not recommend combination therapy against MRSA. However, many clinicians may combine either gentamicin or rifampin with vancomycin if the patient is unresponsive to monotherapy. 

Methicillin-resistant Staphylococcus aureus (MRSA) is a common hospital-acquired pathogen and is also increasing in the community. MRSA has presented a problem in the past because it required treatment with vancomycin. Community-acquired MRSA presents a major therapeutic challenge. MRSA can cause pneumonia, cellulitis, and other infections. Clinicians should be aware of the rate of hospital and community MRSA in your geographic area. New treatment options are available for MRSA. They include linezolid, tigecycline, and daptomycin. Prospective clinical trials have not demonstrated benefits of these agents over vancomycin.36-37... 

Enterococcus spp. 50% resistance to methicillin Resistance to vancomycin greater... 

FCC,b c trimethoprim-sulfamethoxazole, clindamycin ampidllin-sulbadam, or amoxidllinresistant Vancomycin (gentamicin or rifampin)... 

Vancomycin should be added whenever the risk of methicillin-resistant... 

Vancomycin, linezolid, and daptomycin should be used to treat serious infections caused by methicillin-resistantS. aureus. 

In penicillin-allergic patients, oral or parenteral clindamycin may be used. Alternatively, a first-generation cephalosporin such as cefazolin (1 to 2 g IV every 6 to 8 hours) may be used cautiously for patients who have not experienced immediate or anaphylactic penicillin reactions and are penicillin skin test negative. In severe cases in which cephalosporins cannot be used because of documented methicillin resistance or severe allergic reactions to /1-lactam antibiotics, IV vancomycin should be administered. 

For methicillin-resistant staphylococci, use vancomycin 0.5-1 g every 6-12 hours (pediatric dosing 40 mg/kg/day in divided doses) with dosage adjustments made for renal dysfunction. 

Joint replacement S. aureus, S. epidermidis Cefazolin 1 gx 1 preoperatively, then every 8 hours x 2 more doses Vancomycin reserved for penicillin-allergic patients or where institutional prevalence of methicillin-resistant Staphylococcus aureus warrants use IA... 

Linezohd (Zyvox) is an oxazolidinone, a tive-membered heterocychc ring that forms the core of the hnezohd structure. The approval of hnezohd by the FDA in 2000 marked the first new structural class of antibacterial introduced into medical practice in the United States in 40 years. It is notable for its activity against methicillin-resistant Staph aureus, MRSA, and vancomycin-resistant Enterococcus faecium, VRE. It is bacteriostatic rather than bactericidal but finds significant use in patients with an intact immune system. Like several other classes of antibacterials, linezolid is an inhibitor of protein synthesis. It interacts specifically with the RNA component of a bacterial ribosome subunit to prevent initiation of protein synthesis. 

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