In vitro activity of cefonicid compared to other antibiotics against clinical bacterial isolates.

The in vitro activity of cefonicid compared to that of other antibiotics has been evaluated against 401 Enterobacteriaceae, 20 H. influenzae, 17 Branhamella catarrhalis and 71 staphylococci. Cefonicid was always more active than cefazolin, and usually more active than cefamandole and cefuroxime against susceptible gram-negative organisms (E. coli, P. mirabilis, Klebsiella, Shigella, Salmonella, H. influenzae). Cefonicid was ineffective against most strains of Enterobacter, Citrobacter, S. marcescens and M. morganii. Staphylococci were 6 to 8 times less susceptible to cefonicid than to the other cephalosporins.