Morganella is a topic covered in the Johns Hopkins Antibiotic (ABX) Guide.

To view the entire topic, please or purchase a subscription.

Johns Hopkins Guides provide diagnosis, management, and treatment guidance for infectious diseases, diabetes, and psychiatric conditions. Explore these free sample topics:

Johns Hopkins Guides

~~ The first section of this topic is shown below ~~


  • Facultative anaerobic Gram negative rod.
    • Non-lactose fermenter in the same family as Proteus.
    • Environmentally ubiquitous, part of normal colonic flora.
    • "Urea splitter," but stones seen less frequently than Proteus due to less effective urease enzyme.
  • Morganella only has single member in its genus M. morganii, and two subspecies: M. morganii and M. sibonii, which differ only in trehalose fermentation.
  • Antimicrobial susceptibility:
    • Naturally resistant to penicillin, 1st-2nd generation cephalosporins, macrolides, sulfamethoxazole .
    • Beta-lactamase is inducible, chromosomal AmpC type. May confer resistance to imipenem in some isolates.
    • Tigecycline not reliably effective due to ArcAB efflux pump, although may show synergy in vitro with other antimicrobials [6].
    • Extended spectrum beta-lactamases, inducible beta-lactamases, carbapenemases including New Delhi metallo-β-lactamase 1 (NDM-1) and fluoroquinolone resistance reported.

~~ To view the remaining sections of this topic, please
or purchase a subscription ~~

Last updated: December 4, 2014