Cephalosporins
Mnemonic
Cephalosporins are LAME: 1st–4th generation cephalosporins do not act against
- Listeria
- Atypical organisms (e.g., Chlamydia, Mycoplasma)
- No cell wall
- MRSA
- Enterococci (with the exception of ceftaroline, which does act against MRSA).
Mechanisms of drug resistance
| Type of resistance | Example mechanisms | Example antibiotics affected |
|---|---|---|
| Increased drug efflux pump | • New membrane transport system | • Tetracyclines, fluoroquinolones |
| Drug-inactivating enzyme | • Beta-lactamase • Acetyltransferase | • Penicillins, cephalosporins • Aminoglycosides |
| Decreased drug uptake | • Mutated porin protein | • Penicillins, fluoroquinolones |
| Modified drug target | • Altered penicillin-binding protein • Altered ribosomal protein • Altered DNA gyrase | • Penicillins • Aminoglycosides, macrolides • Fluoroquinolones |