Gram-negative organisms aminoglycosides

Intra-abdominal operations necessitate broad-spectrum coverage of gram-negative organisms and anaerobes. Anti-anaerobic cephalosporins, cefoxitin and cefotetan, are useful but suffer from limited availability. Fluoroquinolones or aminoglycosides, paired with clindamycin or metronidazole, should provide adequate coverage for intra-abdominal operations. 

Aztreonam may be used as a substitute for an aminoglycoside in the treatment of infections caused by susceptible gram-negative organisms. Most of the adverse effects of aztreonam are local reactions at the site of injection. Interestingly, aztreonam rarely causes allergic reactions in patients with a history of type I hypersensitivity to other (3-lactam antibiotics. 

Streptomycin (29) have a relatively narrow spectrum of activity which includes both Grampositive and Gram-negative organisms. They are used to control mastitis and enteric disease, and, in the case of streptomycin, calf pneumonia. They are sometimes employed in combination with jS-lactams, to broaden spectrum. The aminoglycosides are quite seriously toxic. Neomycin (27) can cause kidney toxicity, whilst streptomycin (29) has neurotoxicity which can lead to deafness. This toxicity is reflected in the low recommended doses 2-10 mg kg, 10-40 mg kg for streptomycin (29). Resistance to these agents can rapidly be developed. 

Tobramycetin tobramycin, tobramycin [ban, inn, jan, usan] (nebramycin VI Tobramycetin etc.) is an (aminoglycoside) ANTIBIOTIC. Clinically, it has ANTIBACTERIAL properties, and is mainly used against Gram-negative organisms by systemic administration (it is not absorbed orally). tobuterol terbutaline. 

Bone infections in patients with a history of intravenous drug abuse require coverage for gram-negative organisms therefore, empirical treatment with ceftazidime 2 g intravenously every 8 hours plus an aminoglycoside is indicated. If compliance can be ensured, these patients are excellent candidates to receive oral ciprofloxacin 750 mg twice daily. Antibiotic therapy in these patients should be continued for at least 4 to 6 weeks. 

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