In-vitro antibacterial activity of cefepime: a multicentre study

Abstract

The antimicrobial activity of cefepime, a new broad-spectrum parenteral cephalosporin, was evaluated in vitro against 1757 recent clinical Gram-positive and Gram-negative isolates. Cefepime was active at low concentrations (MIC50 values < or = 0.06 mg/L and MIC90 values < or = 0.12 mg/L) against non-cephalosporinase-producing Enterobacteriaceae (Escherichia coli, Proteus mirabilis, Salmonella spp. and Shigella spp.). For Klebsiella pneumoniae, MICs were between 0.016 and 16 mg/L; the highest MIC values were observed for extended-spectrum beta-lactamase-producing strains. Against Enterobacteriaceae, such as cephalosporinase producing Enterobacter cloacae, MICs were < or = 0.5 mg/L, but MICs against cephalosporinase hyperproducing strains were generally higher. Ticarcillin-sensitive strains of Pseudomonas aeruginosa were inhibited by cefepime concentrations of 0.5-16 mg/L, while cefepime MICs were 8-64 mg/L for strains resistant to ticarcillin. The cefepime MIC50 value for Haemophilus spp. including many resistant to amoxycillin, was 0.03 mg/L. Against methicillin-sensitive strains of Staphylococcus aureus, cefepime MICs were 0.5-16 mg/L; MICs against methicillin-resistant staphylococci were 16- > 128 mg/L). Against methicillin-sensitive coagulase-negative staphylococci, cefepime MIC values were 0.03-16 mg/L; corresponding values for methicillin-resistant strains were 2-128 mg/L. Streptococci (Groups A, C and G) were sensitive to cefepime with MICs ranging from < or = 0.008-2 mg/L (MIC50, 0.03 mg/L; MIC90, 0.25 mg/L). The activity of cefepime against Group B streptococci and pneumococci were comparable, with MIC50 values of 0.12 and 0.25 mg/L, respectively, and MIC90 values of 0.03 and 0.25 mg/L, respectively. Most enterococci and all Listeria monocytogenes strains had MICs > or = 32 mg/L.(ABSTRACT TRUNCATED AT 250 WORDS)

In vitro Susceptibility of <i>Listeria monocytogenes</i>: Comparison of the E Test with the Agar Dilution Test

“…Like Hof [19], Espaze and Reynoud [20], Marklein [21] and Kayser et al [22], we also found some isolates susceptible to cefotaxime [19][20][21][22], We cannot confirm the general efficacy of this antibiotic against L. monocytogenes as described by Ahonkhai et al [23], Larrson et al [24] reported that all of their L. monocyto genes strains were resistant to cefotaxime. All L. monocytogenes strains tested were resistant against ceftriaxone [18,24], The activity of Chemotherapy 1997;43:303-310the fourth generation cephalosporins against L. monocytogenes is also unsatisfactory [25], We found a wide range of MICs of cefpirome; the MIC50 values were in the resistance range. As previously described by others, the cephamycin cefoxitin showed no activity against Listeria in vitro [24], Marklein [21 ] found 1 of 44 L. monocytogenes isolates to be cefoxitin susceptible.…”

Comparative Activity of Several Antimicrobial Agents against Nosocomial Gram‐Negative Rods Isolated across Canada

“…These dif fer ences en hance the spec trum of bac te ri cidal ac tivity of ce fepime rela tive to all avail able cepha lo sporins (13). Other stud ies have dem on strated that Gram-negative isolates that are re sis tant to one or more third-generation cephalo sporins are sus cep ti ble to ce f epime (14,15). In a re cent Ca na dian sur vey, it was de ter mined that 23% of iso lates of En tero bac ter cloa cae were cef tazidime re sis tant (16).…”

Is there a rationale for the continuous infusion of cefepime? A multidisciplinary approach

“…Therefore, the goal of therapy is to maintain serum drug concentrations above the minimum inhibitory concentration (T > MIC) for the relevant pathogen over most of the dosing interval [1,2]. When aminoglycosides and fluoroquinolones are considered as concentration-dependent antibiotics, b-lactam antibiotics exhibit time-dependent bactericidal activity.…”

“…When aminoglycosides and fluoroquinolones are considered as concentration-dependent antibiotics, b-lactam antibiotics exhibit time-dependent bactericidal activity. Therefore, the goal of therapy is to maintain serum drug concentrations above the minimum inhibitory concentration (T > MIC) for the relevant pathogen over most of the dosing interval [1,2]. Consequently, for therapeutic purposes, it seems justified to update the data in favor of continuous infusion with b-lactam antibiotics, in particular with cefepime, considering its activity mechanism and spectrum.…”