Staphylococci aminoglycoside antibiotics

However, the newer fluoroquinolone derivatives show superior activity against Enterobacteriaceae and Ps. aeruginosa, and their spectrum also includes staphylococci but not streptococci. Extensive studies with norfloxacin have demonstrated that its broad spectrum, high urine concentration and oral administration make it a useful drug in the treatment of urinary infections. Ciprofloxacin may be used in the treatment of organisms resistant to other antibiotics it can also be used in conjunction with a p-lactam or aminoglycoside antibiotic, e.g. when severe neutropenia is present. 

Aminoglycoside antibiotics, such as gentamicin, kanamycin, streptomycin, and neomycin, inhibit protein synthesis by binding to the 30S ribosomal subunit. Aminoglycosides have been used widely to treat staphylococcal infections and are still often useful, in combination with other antistaphylococcal agents. However, resistance to aminoglycosides among staphylococci is well documented. 

As this category of penicillins was used for treatment, S. aureus and S. epidermidis became resistant to them through the production of altered penicillin-binding proteins. These strains of staphylococci are called methicillin resistant, which denotes resistance not only to all penicillinase-resistant penicillins but to all penicillin drugs. Methicillin-resistant staphylococci have become a major problem in treatment because they are also resistant to the cephalosporins, aminoglycosides, and macrolides. For this reason vancomycin, a more toxic antibiotic, is the drug of choice for these organisms. 

Produced by Screpiomyces orienmJis bacteriocidal antibiotic oral and intravenous formulations Eli Lilly product, Vancocin, is considered current last line of defense against p-lactam- and aminoglycoside-resistant enterococci and methi-cillin-resistant staphylococci, among other uses use is limited by renal toxicity problems at least partly caused by difficulties with purity. 

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