Cefoxitin activity

Against which class of organisms is cefoxitin active ... 

Parenterally administered cephalosporins that are metabolically stable and that are resistant to many types of jS-lactamases include eefuroxime, cefamandole, cefotaxime and cefoxitin, which has a 7a-methoxy group at R. Injectable cephalosporins with anti-pseudomonal activity include cefsulodin and cefoperazone. 

Serious infections requiring intravenous antimicrobial therapy can be treated with a /S-lactam//S-lactamase inhibitor combination or second-generation cephalosporin with activity against anaerobes (cefoxitin). 

Treatment options for patients requiring intravenous therapy include /J-lactam-/3-lactamase inhibitors (ampicillin-sulbactam or piperacillin-tazobactam), second-generation cephalosporins with antianaerobic activity (cefoxitin), and carbapenems. 

A cephalosporin with antianaerobic activity such as cefoxitin or cefotetan is currently recommended as a first-line agent. Cefotetan may be superior for longer operations because of its longer duration of action. 

Second-generation cephalosporins (cefuroxime, cefamandole, cefoxitin, cefotetan, cefaclor, and others) are characterized by high activity with respect to Gram-positive microorganisms that are resistant to beta-lactamase action. They do not have a noticible effect on enterococci. 

Urinary excretion is the major elimination path for most cephalosporins. When prescribing cephalosporins to patients with renal failure, practitioners must consider dose reduction or dose interval extension (Table 45.2). Renal tubular secretion contributes to the elimination of some cephalosporins, and an increase in cephalosporin plasma concentrations may occur when probenecid blocks renal tubular secretion of cephalosporins. Biliary elimination is important for some cephalosporins. Cefmetazole, cefoperazone (Cefobid), cefoxitin, and ceftriaxone achieve biliary concentrations greater than those in plasma. After parenteral administration of cefoperazone, 70% of the dose appears in the bile within 24 hours. Practitioners should decrease the dose of cefoperazone when prescribing for patients with hepatic failure or biliary obstruction. Metabolism is not a major elimination path for most cephalosporins. Cefotaxime is one of the few cephalosporins having an active metabolite, desacetyl cefotaxime. 

Penicillins (bactericidal inhibit cell wall crosslinking) e.g., benzylpenicillin, phenoyxmethylpenicillin, ampicillin, amoxicillin, flu-cloxacillin, methicillin, piperacillin Cephalosporins (bactericidal inhibit cell wall crosslinking) e.g., cefaclor, cefalexin, cefradine, cefuroxime, cefazolin, cefotaxime, ceftriaxone, cefoxitin, cefsulodin, ceftazidime, ceftizoxime Monobactams (bactericidal, P-lactam-like activity) e.g., aztreonam... 

Cefotetan, cefoxitin Intravenous, second-generation drugs, activity versus Bacteroides fragilis allows for use in abdominal/pelvic infections... 

Sutton, S.C., E.L. LeCluyse, L. Cammack, and J.A. Fix. 1992. Enhanced bioavailability of cefoxitin using palmitoyl L-carnitine. I. Enhancer activity in different intestinal regions. Pharm Res 9 191. 

Moxalactam is active against most commonly encountered anaerobic bacteria (6,10,14,23-25,29,30,35-37) and is more active against certain strains than cefotaxime, cefoperazone, and cefoxitin. For many isolates, the concentration of moxalactam required for bactericidal activity is the same as or twofold greater than the MIC (23,27,28). For most bacterial strains, increasing the inoculum size has little or no effect on the MIC of moxalactam (6,9,10,13,16,21). 

Correct choice = E. Unlike the penicillins, cephalosporins are less sensitive to p-lactamase activity. Inflammation does increase penetration of penicillin into the CSF. All penicillin derivatives, including penicillin V, can potentially trigger an allergic reaction in patients sensitive to penicillin G. Cefoxitin can often be used in these patients. However, caution should be exercised, since there is about 5 to 15% crossreactivity. 

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