Gram positive

• Most Streptococci

• Enterococcus faecalis

• Staph aureus (MSSA)

Gram negative

• Many Enterobacteriaceae

• Neisseria spp.

• Haemophilus

• Moraxella

• Pasteurella

Anaerobes

• Bacteroides fragilis

• Prevotella

• non-difficile Clostridia

• Peptostreptococci

• Actinomyces