- G(-) rod, facultative anaerobe (can survive in anaerobic environment if necessary)
- Inherently resistant to aminopenicillins (ampicillin, amoxicillin), cefazolin, and cefoxitin
- Resistance due to production of "AmpC", a beta-lactamase which the organism can increase production of during therapy when exposed to certain beta lactams.
- Assume AmpC is being produced!
- Use cefepime, a carbapenem, or a non beta-lactam even if cultures show sensitivity to other beta-lactams (and especially if patient has received doses of other beta lactams during their stay), otherwise may lead to resistance development during therapy and treatment failure.
- Once sensitivities are available, de-escalation to a non-beta-lactam is possible if sensitive
- 4th most common cause of VAP (after S. aureus, Pseudomonas, Klebsiella)
- 4th most common G(-) rod
- 8th most common hospital-acquired organism