An evaluation of recently developed antibiotics.

A number of newer antibiotics, broad-spectrum penicillins and cephalosporins, have been evaluated against Gram-negative rods. The organisms were selected for multi-resistance and transferable resistance factors. None of the broad-spectrum penicillins was much use against most of the organisms. Ceftriaxone, cefotaxime, latamoxef (moxalactam) and N-formimidoyl thienamycin were all highly effective against most multi-resistant Gram-negative bacilli; cefoperazone being inferior to them. Enterobacter and Serratia strains were relatively resistant to all the agents mentioned and against Acinetobacter only N-formimidoyl thienamycin showed much activity. Thus, use of these drugs may increase the proportion of infections due to organisms such as Serratia or Acinetobacter.