Risk factors and Intestinal Microbiota: Clostridioides difficile Infection in Patients Receiving Enteral Nutrition at Intensive Care Unit

Abstract

Background: Clostridioides difficile infection (CDI) is a leading cause of nosocomial diarrhea. Patients receiving enteral nutrition (EN) in the intensive care unit (ICU) are potentially at high risk of CDI. Presently, we assessed the risk factors and intestinal microbiome of these patients to better understand the occurrence and development of CDI. Methods: Patients were screened for C. difficile every week after EN started and their clinical records were collected for risk factor identification. Feces were analyzed for 16S rRNA sequencing to evaluate the intestinal microbiota. Results : Overall incidence of CDI was 10.7% (18/168 patients). History of cerebral infarction was associated with CDI occurrence (OR, 9.759; 95% CI, 2.140-44.498) and treatment with metronidazole could be protective (OR, 0.287; 95% CI, 0.091-0.902). Patients with EN had lower microbial richness and diversity, accompanied by reduced abundance of Bacteroides , Prevotella_9, Ruminococcaceae and Lachnospiraceae. Of these patients, acquisition of C. difficile resulted in a transient increase in microbial diversity, along with consistent alterations in the proportion of some bacterial taxa, especially Ruminococcaceae and Lachnospiraceae. At the initiation of EN, patients who were positive for C. difficile later had enhanced abundance of Bacteroides , which was negatively correlated with C. difficile load when CDI developed. Conclusion : ICU patients receiving EN had a high prevalence of CDI, and a fragile intestinal microbial environment. Alteration of microbiota composition could be vital in the process of CDI development, bringing new insights in the interaction between C. difficile and host microbiome.