Cefepime activity

Approximately 30% to 40% of H. influenzae are ampicillin resistant. For this reason, many clinicians use a third-generation cephalosporin (cefotaxime or ceftriaxone) for initial antimicrobial therapy. Once bacterial susceptibilities are available, ampicillin may be used if the isolate proves ampicillin sensitive. Cefepime and fluoroquinolones are suitable alternatives regardless of /1-lactamase activity. 

Third-generation cephalosporin ceftriaxone, cefotaxime, cefepime. Note that cephalosporins are not active against Listeria. cCarbapenem imipenem-cilastatin, meropenem. 

Fourth-generation cephalosporins (cefepime and cefpirome) are active with respect to a broad spectrum of Gram-positive and Gram-negative aerobes. They have an unusually low affinity with beta-lactamase and the ability to quickly pass through the periplasmatic space. 

Fourth-generation cephalosporins were developed such as cefpirome and cefepime with additional activity against gram negative pathogens and greater stability against beta-lactamases. 

Cefepime Intravenous, fourth-generation drug, broad activity with improved stability to chromosomal (3 lactamase... 

The mechanism of hydrolysis of cefepime by the class A TEMpuci9 /3-lactamase has been investigated <1996JA7441>. Models for the active-site binding of this antibiotic indicate severe steric interactions between the... 

H. parainfluenzae (MIC, 0.03-0.25 mg I. ) [150], M. catarrhalis (MIC90 0.03-0.125 mg L"1) [149,151,182] and K. pneumoniae [33,182,187,188], although its activity against specific bacteria is less powerful than that of ciprofloxacin [188]. When moxifloxacin was used in combination with cefepime or piperacilhn/tazobactam against clinical isolates of K. pneumoniae, Enterobacter cloacae and Acinetobacter baumannii, an increase in bactericidal activity was obtained compared to that of the individual compounds this was due to synergistic effects between the different compounds [189]. 

Jung R, et al. Synergistic activities of moxifloxacin combined with piperacil-lin-tazobactam or cefepime against Klebsiella pneumoniae, Enterobacter cloacae, and Acinetobacter baumannii clinical isolates. Antimicrob. Agents Chemother., 2004, 48, 1055-1057. 

Fourth-Generation Cephalosporins. The fourth-generation cephalosporin, cefepime, has an extended spectrum of activity against both gram-positive (e.g., methicillin-sensitive S. aureus) and gram-negative organisms (e.g.. Pseudomonas). 

Kalman, D. Barriere, S.L. Johnson, B.L., Jr. Pharmacokinetic disposition and bactericidal activities of cefepime, ceftazidime, and cefoperazone in serum and blister fluid. Antimicrob.Agents Chemother., 1992, 36, 453-457... 

Cejpodoxime proxetil is an orally administered third-generation agent that is very similar in activity to the fourth-generation agent cefepime (see below) except that it is not more active against Enterobacter or Pseudomonas spp. 

It is, however, pertinent to state here that cefepime definitely exhibits an improved antibacterial profile against Streptococcus pneumoniae and Staphylococcus aureus in comparison to the third-generation cephalosporins. Interestingly, its specific activity against P. aeruginosa is found to be variable just like other antibiotics and the profile of activity resides between that of ceftazidime and ceftoxime. 

No activity observed, E. coli isolates (resist to trimethoprim-sulfamethoxazole, cefepime, tazobactam), P. aeruginosa isolates (resist to Trimethoprim-Sulfamethoxazole, tazobactam), P.mirabilis isolates (resist to trimethoprim-sulfamethoxazole, cefepime, tazobactam), K. pneumoniae isolates (resist to trimethoprim-sulfamethoxazole, amoxicillin clavulonate, ceftriaxone, cefepime, aztreonam)... 

Johnson CC, Livornese L, Gold MJ, Pitsakis PG, Taylor S, Levison ME. Activity of cefepime against ceftazidime-resistant gram-negative bacilli using low and high inocula. J Antimicrob Chemother 1995 35 765-773. 

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