Staphylococcus aureus infections vancomycin-resistant

Dhawan B, Gadepalli R, Kapil A. (2009) In vitro activity of daptomycin against Staphylococcus Aureus and vancomycin-resistant Enterococcus Faecium isolates associated with skin and soft tissue infections First results from India. Diagn Microbiol Infect Dis 65 196-198. 

It is often reserved as the drug of last resort . Vancomycin has increasingly become a first-line therapy in resistant Staphylococcus aureus infections. Vancomycin prevents NAM acid and NAG-peptide subunits from being incorporated into the peptidoglycan matrix the large hydrophilic molecule forms hydrogen-bond interactions with the terminal D-alanyl-D-alanine moieties of the NAM/NAG-peptides (Figure 20.8). 

Some of the most clinical significant bacteria involved in drug-resistant infections include (Table 6.1) Acinetobacter baumannii, P aeruginosa, Escherichia coli and Klebsiella pneumoniae resistant to j lactamases, along with methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Staphylococcus aureus (VRSA), and Mycobacterium tuberculosis. (Alekshun and Levy 2(X)7 Lee et al. 2008 Ojha et al. 2008 Weigel et al. 2007). Resistance mechanisms allow bacteria... 

Hotta, K., Saito, N., Okami, Y. Studies on a new aminoglycoside antibiotic, istamycins, from an actinomycete isolated from a marine environment. JAntibiot. 1980, 33,1502-1509. Hsueh, P. R., Chen, W. H., Teng, L. J., Luh, K. T. Nosocomial infections due to methiciUin-resistant Staphylococcus aureus and vancomycin-resistant enterococci at a University Hospital in Taiwan from 1991 to 2003 resistance trends, antibiotic usage and in vitro activities of newer antimicrobial agents. Int J Antimicrob Ag. 2005,26(1), 43 9. Kharat, K., Kharat, A., Hardikar, B. P. Antimicrobial and cytotoxic activity oiStreptomyces sp. from Lonar Lake. Afr JBiotechnol. 2009, 8(23), 6645-6648. 

Most appropriate use is when vancomycin-resistant Enterococcus faecium infection is documented or strongly suspected, or for oral therapy of methicillin-resistant Staphylococcus aureus infection... 

Stevens DL, Herr D, Lampiris H, et al, and the Linezolid MRSA Study 44. Group. Linezolid versus vancomycin for the treatment of methicillin-resistant Staphylococcus aureus infections. Clin Infect Dis 2002 34 45. 

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. 

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... 

Vancomycin and teicoplanin display excellent activity against staphylococci and streptococci, but because of the wide availability of equally effective and less toxic drugs, they are second-line drugs in the treatment of most infections. As antistaphylococcal agents they are less effective than 3-lactam cephalosporin antibiotics, such as nafciUin and cefazoUn. They have attained much wider use in recent years as a consequence of the emergence of methicUlin-resistant S. aureus (MRSA) infections, in particular the growing importance of Staphylococcus epidermidis infections associated with the use of intravascular catheters and in patients with peritonitis who are on continuous ambulatory peritoneal dialysis. 

S. A. Roberts, J. Robson, K. Read, N. Bak, J. Hurley, P.D.R. Johnson, A.J. Morris, B.C. Mayall, and M.L. Grayson (2004). Treatment outcomes for serious infections caused by methicillin-resistant Staphylococcus aureus with reduced vancomycin susceptibility. Clinical Infectious Diseases 38 521-528. 

Hiramatsu K. Vancomycin-resistant Staphylococcus aureus A new model of antibiotic resistance. Lancet Infect Dis 2001 1 147. [PMID 11871491]... 

Antistaphylococcal penicillins Methicillin [meth i SILL in], naf-cillin [naf SILL in], oxacillin [ox a SILL in], cloxacillin [klox a SILL in], and dicloxacillin [dye klox a SILL in] are penicillinase-resistant penicillins. Their use is restricted to the treatment of infections caused by penicillinase-producing staphylococci. Because of its toxicity, methicillin is rarely used. Methicillin-resistarft strains of Staphylococcus aureus (MRSA), currently a serious source of nosocomial (hospital-acquired) infections, are usually susceptible to vancomycin, and rarely to ciprofloxacin or rifampin. 

Answer Yes. Vancomycin is the drug of choice (in fact, the only effective drug currently available) for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. It is bactericidal and thus important for treatment of a leukopenic individual. 

Methicillin-resistant strains of Staphylococcus aureus and S. epidermidis and penicillin-resistant Streptococcus pneumoniae have been isolated from ocular infections. Therefore treatment of ocular infections caused by these organisms might require use of vancomycin for resolution. Vancomycin is also recommended for empiric intra-vitreal and topical therapy in bacterial endophthalmitis and for parenteral therapy in moderate to severe preseptal cellulitis (see Table 11-1). 

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