Serratia marcescens- a rare opportunistic nosocomial pathogen and measures to limit its spread in hospitalized patients

Background: In November 2011, 6 patients who were in the ICU of the Sri Guru Ram Dass Institute of Medical Sciences and Research acquired an infection which was caused by Serratia marcescens. We investigated the cause of the increase in frequency of the isolation of Serratia marcesens from hospitalized patients.

Methods: Various samples from patients and environmental sources, which were collected from the ICU of Sri Guru Ram Das Institute of Medical Sciences and Research during the 6 month period from November 2011 to April 2011, were included in the study. The isolates from the patients and the surrounding environmental sources were examined by using standard techniques. Further, the isolates of Serratia marcescens were identified, depending upon their biochemical and morphological characteristics.

Results: Seven isolates of Serratia marcescens were identified (six from the patients in the ICU and one from the soap dispenser in the ICU) among a total of 327 isolates from the clinical samples and 84 isolates were identified from the environmental sources in the ICU.

Discussion and conclusion: An outbreak of the Serratia marcescens infection in the ICU was traced to the extrinsic contamination of the soap dispenser in the ICU, as after the removal of the dispenser, no further case occurred.