[Evaluation of the so-called basic cephalosporins using the serum bactericidal test].

The serum bactericidal activity (SBA) was studied one hour and four hours after intravenous administration of 1 g and 2 g cefotiam, 1.5 g cefuroxime and 2 g cefazolin to six volunteers. The 136 clinical isolates tested included Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and Haemophilus influenzae. One hour after administration no significant differences in the activity against staphylococci were noted in the antibiotics tested. Four hours after administration of cefazolin 96% of the Staphylococcus aureus strains were killed at a serum dilution of 1:8, whereas only one strain was killed by cefuroxime and none by cefotiam under the same conditions. The highest SBA-titers against Haemophilus influenzae were achieved with cefotiam at a dosage of 2 g. SBA-titers against Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis were higher after administration of 1 g cefotiam than after administration of 1.5 g cefuroxime and 2 g cefazolin, respectively.