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)