Organisms that carry a genetic element for carbapenem resistance also have resistance to multiple other antibiotic classes including Penicillins, Cephalosporins, Carbapenems, Fluoroquinolones, and Aminoglycosides.
There are only a few antibiotics that can treat infections of gram-negative organisms that have acquired a Carbapenemase-resistance, and resistance to those antibiotics can also develop.
The genetic element providing Carbapenum-resistance is mobile. It can jump from one bacteria to another and has been documented doing so in several case studies of hospital outbreaks. If we ever encounter a gram negative organism that is resistant to Carbapenem antibiotics we will likely want to consider further susceptibility testing.
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