Final answer:
Empiric therapy with gram-negative PCN antibiotics involves the use of broad-spectrum antibiotics to treat infections before the exact cause is identified. These antibiotics are effective against a range of gram-negative bacteria and are stable for oral administration, but the rise of resistant gram-negative pathogens can complicate treatment.
Step-by-step explanation:
Gram-negative PCN (penicillin) antibiotics are considered 'empiric therapy' because they are broad-spectrum antibiotics used when the specific bacteria causing an infection have not been identified. Empiric therapy is a form of treatment initiated before a definitive diagnosis is made, based on the clinical presentation and likely causative agents. In the context of gram-negative bacteria, PCN antibiotics like ampicillin and amoxicillin are designed to combat a wider range of bacteria, including Escherichia coli (a common gram-negative bacterium), and are stable in the acidic environment of the stomach for effective oral administration.
The ability of gram-negative bacteria to develop resistance through efflux pumps or mechanisms that limit antibiotic uptake like porin channel alterations underlines the challenge in treating such infections. This has led to the rise of Extended-Spectrum β-Lactamase-Producing (ESBL) Gram-Negative Pathogens and Carbapenem-Resistant Gram-Negative Bacteria (CRGNB). Consequently, empiric antibiotic therapy often must employ more potent antibiotics with broader effects to ensure effectiveness against these multi-drug resistant organisms, while awaiting more specific microbiological data.