In vitro susceptibility tests with cefoperazone compared with cefotaxime, cefoxitin, cefuroxime, cephaloridine and gentamicin.

Minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs) and sensitivity disc tests of cefoperazone, cefotaxime, cefoxitin, cefuroxime, cephaloridine and gentamicin were determined from 300 Gram-positive and -negative isolates from kidney transplant recipients. Cefoperazone inhibited 50% of Pseudomonas aeruginosa strains at a concentration of 6.25 micrograms/ml. Only gentamicin had similar activity but if we consider the sources of our strains and the nephrotoxicity of the compound, its use is not suitable. Moreover, cefoperazone was able to inhibit from 50% to 90% of the other strains at variable concentrations between 0.39 micrograms/ml and 3.12 micrograms/ml.