Morganellaceae

• A family of Gram-negative bacilli that cause infections (commonly UTIs) in humans
• Includes the following genera:
  • Morganella
  • Proteus
  • Providencia
• Notably, members of this family are intrinsically resistant to:
  • Colistin
  • Tetracyclines (including tigecycline)
    • Except Morganella morganii, which retains susceptibility to doxycycline but not tigecycline
  • Nitrofurantoin
• Intrinsic reduced susceptibility to imipenem
• Often have β-lactamases (including AmpC)