[In vitro testing of newer cephalosporins (author's transl)].

The spectrum of activity of the newer cephalosporins is considerably wider and includes a number of gram-negative bacteria. Test results using cephalothin as 'class disc' of a class of antibiotics is therefore no longer valid for the newer members. Like cefazoline, all of the above-mentioned antibiotics are more effective against Escherichia coli. Cefuroxin and cefoxitin also display increased effectiveness against Klebsiella, as do cefoxitin against Serratia and indolpositive Proteus species, and cefamandole and cefuroxime against Enterobacter. Cefotaxim is superior to all other agents, as was also demonstrated in our own inhibition zone tests; in addition cefotaxim is effective against Pseudomonas aeruginosa. Since the various pathogens do not exhibit a uniform pattern of resistance to these antibiotics, the four new agents should for the time being be tested independently of cephalothin and cefazoline.