AmpC microorganisms: Enterobacter & Citrobacter
Gram negative microorganisms, may have an inducible chromosomal beta-lactamase that causes resistance to many beta-lactams (except carbapenems) with prolonged antibiotic exposure.
Most AmpC organisms are nosocomially encountered, are GI flora and are part of the Enterobacteriaceae family.
Nosocomial infections due to
Urinary tract infections
Hospital-acquired or ventilator-associated pneumonia
Prosthetic device infections and line infections
May require contact precautions if highly resistant.
ESBLs vs. AmpC: Most ESBLs are plasmid-encoded, whereas AmpCs are usually inducible and chromosomal.
SPICEM stands for Serratia, Providencia, (Indole positive) Proteus vulgaris, Citrobacter, Enterobacter, and Morganella.
Locally, Citrobacter and Enterobacter are most likely microorganisms to carry AmpC so are the main AmpC microorganisms of concern.