Concurrent transmission of multiple carbapenemases in a long-term acute-care hospital
Danielle A. Rankin, Maroya Spalding Walters, Luz Dary Caicedo, Paige Gable, Heather Moulton-Meissner, Allison Chan, A. Wesley Burks, Kendra Edwards, Gillian McAllister, Alyssa G. Kent, Alison Laufer Halpin, Christina Moore, Tracy McLemore, Linda Thomas, Nychie Dotson, Alvina Chu
Abstract
Abstract Objective: We investigated concurrent outbreaks of Pseudomonas aeruginosa carrying bla VIM (VIM-CRPA) and Enterobacterales carrying bla KPC (KPC-CRE) at a long-term acute-care hospital (LTACH A). Methods: We defined an incident case as the first detection of bla KPC or bla VIM from a patient’s clinical cultures or colonization screening test. We reviewed medical records and performed infection control assessments, colonization screening, environmental sampling, and molecular characterization of carbapenemase-producing organisms from clinical and environmental sources by pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing. Results: From July 2017 to December 2018, 76 incident cases were identified from 69 case patients: 51 had bla KPC, 11 had bla VIM, and 7 had bla VIM and bla KPC . Also, bla KPC were identified from 7 Enterobacterales, and all bla VIM were P. aeruginosa . We observed gaps in hand hygiene, and we recovered KPC-CRE and VIM-CRPA from drains and toilets. We identified 4 KPC alleles and 2 VIM alleles; 2 KPC alleles were located on plasmids that were identified across multiple Enterobacterales and in both clinical and environmental isolates. Conclusions: Our response to a single patient colonized with VIM-CRPA and KPC-CRE identified concurrent CPO outbreaks at LTACH A. Epidemiologic and genomic investigations indicated that the observed diversity was due to a combination of multiple introductions of VIM-CRPA and KPC-CRE and to the transfer of carbapenemase genes across different bacteria species and strains. Improved infection control, including interventions that minimized potential spread from wastewater premise plumbing, stopped transmission.