Fecal Microbiome Among Nursing Home Residents with Advanced Dementia and Clostridium difficile
Patients colonized with toxinogenic strains of Clostridium difficile have an increased risk of subsequent infection. Given the potential role of the gut microbiome in increasing the risk of C. difficile colonization, we assessed the diversity and composition of the gut microbiota among long-term care facility (LTCF) residents with advanced dementia colonized with C. difficile.
Retrospective analysis of rectal samples collected during a prospective observational study.
Thirty-five nursing homes in Boston, Massachusetts.
Eighty-seven LTCF residents with advanced dementia.
Operational taxonomic units were identified using 16S rRNA sequencing. Samples positive for C. difficile were matched to negative controls in a 1:3 ratio and assessed for differences in alpha diversity, beta diversity, and differentially abundant features.
Clostridium difficile sequence variants were identified among 7/87 (8.04%) residents. No patient had evidence of C. difficile infection. Demographic characteristics and antimicrobial exposure were similar between the seven cases and 21 controls. The overall biodiversity among cases and controls was reduced with a median Shannon index of 3.2 (interquartile range 2.7–3.9), with no statistically significant differences between groups. The bacterial community structure was significantly different among residents with C. difficile colonization versus those without and included a predominance of Akkermansia spp., Dermabacter spp., Romboutsia spp., Meiothermus spp., Peptoclostridium spp., and Ruminococcaceae UGC 009.
LTCF residents with advanced dementia have substantial dysbiosis of their gut microbiome. Specific taxa characterized C. difficile colonization status.
KeywordsMicrobiome Advanced dementia Colonization Clostridium difficile
Dr. D’Agata and Araos contributed to the study concept and design, acquisition of subjects, and collection of the relevant data. Dr. Araos, Ugalde, and D’Agata performed the data analysis. All authors contributed to data interpretation and collaborated on the drafting and revision of the manuscript. Dr. Araos is the guarantor and takes responsibility for the integrity of the data and the accuracy of the data analysis.
This work has been supported by the National Institute of Allergy and Infectious Diseases (K24 AI119158 [EMCD]), the Centers for Disease Control and Prevention’s investments to combat antibiotic resistance under Award Number 200-2016-91939 (EMCD and RA), NIH-NIA R01 AG032982 (SM, EMCD), and NIH-NIA K24AG033640 (SM).
Compliance with ethical standards
Conflict of interest
Juan Ugalde is an employee of uBiome Inc and has received stock options as well as other compensation.
- 1.Clostridium difficile infection in 2015. Centers for Disease Control and Prevention (CDC). Available at: https://www.cdc.gov/media/releases/2015/p0225-clostridium-difficile.html. Accessed July 3, 2017.
- 2.Antimicrobial resistance. Centers for Disease Control and Prevention (CDC). Available at: https://www.cdc.gov/drugresistance/biggest_threats.html. Accessed July 3, 2017.