Microbiology
Aerobic gram-negative rod. S. liquifaciens, S. marcescens, S. odorifera, S. rubidaea, and others.
Epidemiologic Risks
Often invades by way of the respiratory tract. Found in the environment.
Here in the Great Pacific NW, a remarkable number of people are on untreated well water and I have seen a smattering of Serratia infections as a result.
Syndromes
Hospital-acquired infections of all kinds.
Treatment
Often resistant to multiple antibiotics, check your local susceptibility. Quinolones OR ceftazidime OR amikacin OR carbapenems are empiric possibilities.
Notes
It makes a red pigment that allowed the military to use it in the '50s to see how bacteria move in urban environments. For example, the US government sprayed aerosolized Serratia in San Francisco because they could track the organism by using drop plates and seeing how it spread in urban environments. People died. So much for it being a non-pathogen (PubMed).
Its red pigment has also been credited as the cause of bleeding paintings and food in the middle ages. See PubMed.
Curious Cases
Relevant links to my Medscape blog
Last Update: 04/30/18.