Methicillin-resistant Staph, aureus

Early cephalosporins were spelt with ph, more recently with T. t Methicillin-resistant Staph, aureus (MRSA) strains are resistant to cephalosporins. t Enterococci are resistant to cephalosporins. 

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. 

Mupirocin (Fig. 10.16C) is the main fermentation product obtained from Ps. fluorescens. Other pseudomonic acids (B, C and D) are also produced. Mupirocin is active predominantly against staphylococci and most streptococci, but Enterococcus faecalis and Gram-negative bacilli are resistant. There is also evidence of plasmid-mediated mupirocin resistance in some clinical isolates of Staph, aureus. Mupirocin is employed topically in eradicating nasal and skin carriage of staphylococci, including methicillin-resistant Staph, aureus (MRSA) colonization. 

Currently the most important hospital-acquired pathogen is methicillin-resistant Staph, aureus, which is responsible for a range of serious infections such as pneumonia, postoperative wound infection and skin infections which may in turn be complicated by bloodstream spread. The use of vancomycin and teicoplanin has escalated as a consequence, and in turn has been linked to the emergence of vancomycin-resistant enterococci. 

Bacteria are present on everyone s hands and skin. In the simplest terms, some are good bacteria (skin flora may prevent pathogenic organisms from colonizing the skin surface), while other bacteria are dangerous and can induce infection such as Methicillin-resistant Staphylococcus aureus (MRSA) infection, which is caused by a strain of staph bacteria that has become resistant to antibiotics generally used to treat ordinary staph infections. 

It is a glycopeptide antibiotic and primarily active against gram positive bacteria, strains of Staph, aureus which are resistant to methicillin are inhibited by vancomycin. It is also effective against Strep, viridans, enterococcus, Clostridium dijficile and diphtheroids. 

Tea Tree oil was as effective as benzoyl peroxide in reducing the number of scars, but that it had a lower irritant effect on skin. Tea Tree oil has also been shown to have in vitro activity against 60 methicillin-resistant strains of Staph, aureus (MRSA) and was clinically effective in vaginitis and in chronic infections due to Trichophyton species. 

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