Methacillin-resistant staphylococcus aureus

In companion animals, the bacterial infections most frequently requiring treatment involve the skin, wounds, ears, respiratory tract, and urinary tract. Prevalence of resistant bacteria is difficult to assess in pets. Since empirical treatment is common, there is limited information on trends in resistance, and almost no data are available on the magnitude of antimicrobial use in these species. Increasing resistance among E. coli and Staphylococcus isolates from pets has been reported from studies in a number of countries. Methacillin-resistant Staphylococcus aureus (MRSA) have been isolated from dogs and horses, although animal outbreaks have generally been traced to infected humans. ... 

St. John s wort has been used topically for wound healing for hundreds of years. Antibacterial properties have been reported as early as 1959, with hyperforin found to be the active component. Using multiple concentrations, it was discovered that no hyperforin dilutions had antimicrobial effects on Gram-negative bacteria or Candida albicans. There was, however, growth inhibition for all of the Gram-positive bacteria tested, some with the lowest dilution concentration of 0.1 pg/mL. Hyperforin was also shown to be effective at inhibiting methacillin-resistant Staphylococcus aureus (25). 

An unusual use of additives with potential application in hospitals and other environments where cleanliness is paramount, is use of Microban antimicrobial technology. This is capable of killing various harmful bacteria including those responsible for methacillin resistant Staphylococcus aureus (MRSA) and Escherichia coli 0157 with independent tests showing a kill rate of 99% for these two... 

It may seem a far cry from these broad-spectrum penicillins to the methacillin family which are specialized to deal only with Staphylococcus aureus, and (of this species) only members that are resistant because of the )8-lactamase that they carry. The need for these specialized penicillins arose when this resistant organism had established itself in most of the larger hospitals as a highly contagious source of nosocomial infection. Methicillin [6-(2,6-dimethoxy-benzamido)penicillanic acid], the foundation member of this family, was susceptible to gastric acid hydrolysis and was soon replaced by the oxacillins 13.10) all of which are active orally. Of these, dicloxacillin 13.10c) is considered the most powerful and is certainly very effective yet even this drug is not the equal of the original penicillin G for non-resistant staphylococci. Nafcillin, another member of the methicillin family, is now little used because of poor oral availability. 

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