Gram positive: N. asteroides, Staphylococcus (excluding many strains which are methicillin resistant), Streptococcus.

Gram negative: Acinetobacter, Citrobacter, Enterobacter, E. coli, H. influenzae, H. parainfluenzae, Klebsiella, M. morganii, Proteus (indole positive and indole negative strains), Providencia, P. aeruginosa, S. marcescens.

Anaerobes: Clostridium (excluding C. difficile), Peptococcus, Peptostreptococcus, B. fragilis, Bacteroides (non fragilis).