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Whole Genome Sequencing of Candida glabrata for Detection of Markers of Antifungal Drug Resistance
Published on: December 28, 2017
Use of Whole Genome Sequencing to Investigate the Risk for Transmission of Clostridioides difficile From Prior Room
Sarah N Redmond1, Maria M Torres-Teran2, Jennifer L Cadnum2
1Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA.
Background:
Admission to a room previously occupied by a patient with Clostridioides difficile infection (CDI) has been identified as a risk factor for CDI. However, previous studies have not included molecular typing to definitively link healthcare-associated CDI (HA-CDI) cases to prior room occupants.
Methods:
In a hospital and affiliated long-term care facility, we conducted a 1-year cohort study to determine if exposure to a room previously occupied by a CDI patient and/or with environmental contamination after cleaning and disinfection in the past 3 months was associated with an increased risk of HA-CDI. Multivariable logistic regression was used to assess risk factors for HA-CDI. Whole genome sequencing was used to determine the relatedness of HA-CDI isolates and isolates from prior CDI cases or environmental surfaces.
Results:
Of 5,746 admitted patients, 55 were diagnosed with HA-CDI. Exposure to a room previously occupied by a CDI patient and/or with a positive post-discharge culture was not associated with an increased risk of HA-CDI (adjusted odds ratio 1.15, 95% confidence interval 0.65-1.98; P=0.62). None of the 21 HA-CDI patients with prior room-level exposures were infected with isolates genomically related to isolates from prior room occupants with CDI or from room surfaces. Five HA-CDI cases were linked to prior CDI patients or environmental isolates on the same ward or without ward-level exposure.
Conclusion:
Despite frequent exposure to rooms previously occupied by CDI patients or contaminated with C. difficile, no HA-CDI cases were linked to prior room exposures in a facility using sporicidal disinfectants in CDI rooms.

