Comparative in vitro activity of cefepime against nosocomial isolates

Cefepime, a new parenteral cephalosporin, was evaluated for its in vitro antibacterial activity in comparison with other broad-spectrum antibiotics against a total of 445 recently isolated microorganisms of nosocomial origin. Cefepime was highly active against all species of Enterobacteriaceae with minimum inhibitory concentrations (MIC90S) ranging from 0.25-8 micrograms/ml. Cefepime showed moderate activity against Acinetobacter spp (MIC50 and MIC90, 16 micrograms/ml) but its activity was superior to that of any drug tested, except imipenem. Against Pseudomonas aeruginosa its activity was comparable to that of ceftazidime and was greater than that of cefotaxime, aztreonam, ciprofloxacin and aminoglycosides. Of all the agents tested, imipenem was the most active compound. Cefepime was active against Staphylococcus aureus and coagulase-negative methicillin-susceptible staphylococci but it had no activity against methicillin-resistant staphylococci and enterococci.