Cefepime is a fourth generation cephalosporin antibiotic.
TOKU-E offers two forms of cefepime: cefepime (C008), and cefepime HCl (C009). In aqueous solution, cefepime is slightly soluble (17.3 mg/mL) compared to the more soluble cefepime HCL (40 mg/mL). Both forms have similar potencies and are suitable for microbiology use; however, cefepime HCl is easier to work with in aqueous solution because of its higher solubility.
Like β-lactams, cephalosporins interfere with PBP (penicillin binding protein) activity involved in the final phase of peptidoglycan synthesis. PBP’s are enzymes which catalyze a pentaglycine crosslink between alanine and lysine residues providing additional strength to the cell wall. Without a pentaglycine crosslink, the integrity of the cell wall is severely compromised and ultimately leads to cell lysis and death. Resistance to cephalosporins is commonly due to cells containing plasmid encoded β-lactamases. Interestingly, cefepime is resistant to various β-lactamases encoded by otherwise resistant β-lactam bacteria strains.
Cefepime is a broad spectrum antibiotic targeting a wide variety of naturally antibiotic resistant gram positive and gram negative bacteria. Some of these naturally resistant bacteria include Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pneumoniae.
Cefepime is commonly used in clinical in vitro microbiological antimicrobial susceptibility tests (panels, discs, and MIC strips) against gram positive and gram negative microbial isolates. Medical microbiologists use AST results to recommend antibiotic treatment options for infected patients. Representative MIC values include:
- Pseudomonas aeruginosa 32 µg/mL – 256 µg/mL
- Staphylococcus aureus 2 µg/mL – 16 µg/mL
- For a more complete list of cefepime MIC values, click here.
Georgopapadakou, N. H. "Mechanisms of Action of Cephalosporin 3'-quinolone Esters, Carbamates, and Tertiary Amines in Escherichia Coli." American Society for Microbiology 37.3 (1992): 559-65. Antimicrobial Agents and Chemotherapy. Web. 21 Aug. 2012.