**5.8. CAUTI with** *Serratia marcescens*

It is facultative anaerobic bacilli gram-negative rod of Enterobacteriaceae family considered opportunistic human pathogen but not a component of human facial flora. It is capable of producing a pigment called prodigiosin, which ranges in color from dark red to pale pink. It is ubiquitously spent in nature and has preference for damp conditions. Though previously known as nonpathogenic, but since 1970s it is associated with multi drug resistant infection due to presence of R factor—a plasmid. A study in Japan showed 6.8% incidence of UTI with this organism [80]. It also causes bacteraemia rarely. Diagnosis is confirmed by culture of the urine specimen or catheter biofilm. Automated bacterial identification systems and Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) is the other modality for diagnosis of serratia as well as other enterobacteriaceae [81].
