Serratia marcescens
General Susceptibility

General Susceptibility

Carbapenem until susceptibility known, then step down to aminoglycoside or fluoroquinolone if susceptible.

These organisms usually produce inducible beta-lactamase which cause failure of 3rd generation beta-lactam therapy, despite in vitro susceptibility

Inherent resistance to:

  • Penicillins
  • Macrolides
  • 1st gen cephalosporins

Common producer of AmpC beta-lactamases