Characterization of Specific Signatures of the Oral Cavity, Sputum, and Ileum Microbiota in Patients With Crohn’s Disease

Abstract

BackgroundCrohn’s disease (CD) is a chronic nonspecific inflammatory bowel disease (IBD) with an increasing incidence worldwide. The etiology of CD is still obscure, but microbial dysbiosis has been recognized as an essential factor contributing to CD. However, few studies have revealed the microbiome’s signatures and reciprocal correlations between multiple sites in patients with CD over different disease stages. This study investigated the specific microbial architectures of the oral cavity, sputum, and ileum in patients with CD in the active and remission stages.MethodsMicrobial samples from the oral cavity, sputum, and ileum were collected from patients with CD in the active and remission stages and healthy controls. The microbial composition was assessed by 16S ribosomal RNA (rRNA) gene sequencing. In addition, bioinformatics methods were used to demonstrate the microbial signatures, functional changes, and correlations between microbiota and clinical data in CD.ResultsCompared with healthy controls, a distinct microbiota dysbiosis in the oral cavity, sputum, and ileum of patients with CD was identified, characterized by alterations in microbiota biodiversity and composition. The oral cavity and sputum microbiota showed significantly lower microbial diversity in patients with CD than in healthy controls. In terms of microbiota composition, the microbiota changes in the oral cavity of patients with CD were similar to those in the sputum, while they were different from those in the ileum. In the oral cavity and sputum of patients with CD, a lower relative abundance of Firmicutes and Actinobacteria was observed compared to healthy controls, which was most prominent in the active stage. In contrast, an increased relative abundance of Fusobacteria, Porphyromonas, and Haemophilus was observed in patients with CD. The predicted metabolic pathways involved in the oral cavity, sputum, and ileum were similar, predominantly involving metabolism, environmental information processing, and genetic information processing.ConclusionThe results revealed the alterations of microbiota architecture in the oral cavity, sputum, and ileum of patients with CD, which varied across disease stages. Studying microbiota dysbiosis may bring new insights into the etiology of CD and lead to novel treatments.

Alterations and correlations of ileum microbiota and serum metabolites in Crohn's disease

“…While the present study results offer a detailed insight into the alterations of ileum microbiota and serum metabolites in the active and remission stages of CD, some limitations still need to be addressed. Issues about antibiotic exposure in the group of active stage have been discussed previously 20 . Brie y, in an earlier study, microbial samples from the ileal stoma were collected from CD patients in the active stage during surgery.…”

“…The details of DNA extraction, PCR ampli cation, and 16S rRNA gene sequencing have been depicted previously 20 . Brie y, microbial DNA was extracted using an E.Z.N.A.® soil DNA Kit (Omega Bio-Tek, Norcross, GA, U.S.).…”

“…The 16S rRNA gene sequence data sets have been deposited in NCBI Sequence Read Archive under the study accession number PRJNA773617 20 .…”

“…A total of 38 CD patients (19 patients in the active stage and 19 patients in the remission stage) were nally enrolled in the present study (Table 1), as noted previously 20 . The indexes, including age, gender, body mass index, lesion location, duration of disease, and history of life (diet, smoking, and alcohol use), were similar in these individuals (all P > 0.05).…”

Timing of individualized surgical intervention in Crohn’s disease

“…Malnutrition is one of the prominent clinical manifestations of CD. Our team recently published a study indicating that CD patients were at higher nutritional risk than healthy people[ 54 ]. It can hinder wound healing and increase the risk of incision infection, hernia, and anastomotic leak[ 55 ].…”