Colonization of the central venous catheter by Stenotrophomonas maltophilia in an ICU setting: An impending outbreak managed in time

Abstract

Background: Stenotrophomonas maltophiliacauses opportunistic infections in immunocompromised and patients in intensive care units (ICUs). An outbreak of S. maltophilia in ICU is described which highlights the importance of the risk of infection from contaminated medical devices and suction fluids in ventilated patients.

Methods: The investigation of the outbreak was carried out. Environmental sampling was done. This was followed by MALDI-TOF MS typing and recA gene-based-phylogeny.

Results: In February, S. maltophilia was reported from the central line blood of six patients from ICU within a span of two weeks. The peripheral line blood cultures were sterile in all patients. Relevant environmental sampling of the high-touch surface and fluids revealed S. maltophilia strains in normal saline used for suction and in the inspiratory circuit of two patients. The isolated strains from patients and environment (inspiratory fluid) showed a minimum of 95.41% recA gene sequence identity between each other. Strict cleaning and disinfection procedures were followed. Continuous surveillance was done and no further case of S. maltophilia was detected. Timely diagnosis and removal of central line prevented development of central-line associated blood stream infection.

Conclusion: This outbreak report illustrates that environmental sources like suction fluid and normal saline could be the source of S. maltophilia in ICU patients.

Keywords: Central line colonization; Intensive care unit; MALDI-TOF typing; Stenotrophomonas maltophilia; recA molecular typing.