DS 39 - Sink Drain Survey of Carbapenemase-producing Organisms at a Kentucky Academic Medical Center

Background: Carbapenemase-producing organisms (CPOs) are known to colonize hospital sink drains. Our facility has experienced low levels of CPO transmission with concerns that sinks may act as CPO reservoirs. In this study we describe the level of sink drain colonization and characterize CPOs that sink drains harbor.

Methods: Our facility is a 945 bed tertiary care academic medical center in Kentucky. Sink drains and/or p-traps in specific trauma intensive care unit (ICU), acute care, and progressive care rooms were tested for CPOs between January and November 2018. Beginning June 2018, all sink drains were disinfected weekly. A subset of CPOs isolated from sink drains were further analyzed with whole-genome sequencing.

Results: A total of 209 samples were collected from sink drains and p-traps. Nearly 9% of all samples and 34% of all rooms (n=32) were positive for CPOs in sink drains or associated p-traps. Approximately 18% (n=13) of the samples were positive in the trauma ICU compared to only 7% (n=4) in the acute care unit (p=0.04). The most common organisms isolated were Raoutella ornithinolytica (detected in 5 rooms) and Citrobacter freundii (detected in 4 rooms). Carbapenemase enzymes identified in sink drains included Klebsiella pneumoniae carbapenemase (KPC) and Verona integron-encoded metallo-β-lactamase (VIM). Whole-genome sequencing of 14 isolates further identified KPC and VIM carbapenemases as KPC-2, KPC-3, KPC-15, VIM-1 and VIM-18.

Conclusions: Sink drains are considered reservoirs of CPOs at our facility and harbor variants of KPC and VIM carbapenemases. Despite weekly disinfection, some sink drains were intermittently and persistently positive for CPOs. These data suggest that disinfects used in this study are not a reliable long term solution for removal of CPOs. Efforts to reduce CPO colonization of sink drains and CPO transmission should also include sink hygiene interventions (e.g., splash guards, education, appropriate waste disposal, etc).