Alteration of the Fecal but Not Salivary Microbiome in Patients with Behçet’s Disease According to Disease Activity Shift

Abstract

The human microbiome plays an important role in various diseases, including Behçet’s disease (BD). However, the effects of disease activity and covariates influencing the microbial composition have not yet been investigated. Therefore, we investigated the fecal and salivary microbiomes of BD patients compared to those of recurrent aphthous ulcer (RAU) patients, as well as dietary habit-matched healthy controls (HCs) selected from immediate family members using 16S rRNA gene sequencing. The fecal microbiome alpha diversity of BD patients was not different from that of their matched HCs, although it was higher than that of unrelated HCs and decreased in BD patients with disease activity. A tendency toward clustering in the beta diversity of the fecal microbiome was observed between the active BD patients and their matched HCs. Active BD patients had a significantly higher abundance of fecal Bacteroides uniformis than their matched HCs and patients with the disease in an inactive state (p = 0.038). The abundance of salivary Rothia mucilaginosa group was higher in BD patients than in RAUs patients. BD patients with uveitis had different abundances of various taxa, compared to those without uveitis. Our results showed an association of fecal microbiome composition with BD disease activity and symptoms, suggesting the possible role of the gut microbiome in BD pathogenesis.

Metformin Contributes to the Therapeutic Effects of Acne Vulgaris by Modifying the Gut Microbiome

“…After performing 16s rDNA sequencing of fecal samples, we observed signifcantly decreased microbial diversity in individuals with acne vulgaris, which then increased to health levels after three months of the metformin therapy. A decreased diversity in gut microbiota in patients with acne and other infammatory skin diseases, such as Behçet's disease and psoriasis, was also reported in previous studies [25,26]. It has been reported that individuals who have low bacterial richness have a more pronounced infammatory phenotype [27].…”

Microbiome and immune-mediated dry eye: a review

“…In 22 individuals with Behcet’s, a significant depletion in the genera Roseburia and Subdoligranulum , two Clostridium clusters, was found when compared with 16 healthy controls 7. Yet in another study involving nine individuals with Behcet’s, the abundance of Bacteroides uniformis was significantly higher than in 9 healthy controls, but the significant bacterial differences found in the first study were not demonstrated 33. Finally, in a study involving 35 individuals who underwent allogeneic haematopoietic stem cell transplantation, patients microbiomes were sampled at the time of acute (aGVHD) onset and compared with 35 post-transplant individuals without GVHD.…”

“… 7 Yet in another study involving nine individuals with Behcet’s, the abundance of Bacteroides uniformis was significantly higher than in 9 healthy controls, but the significant bacterial differences found in the first study were not demonstrated. 33 Finally, in a study involving 35 individuals who underwent allogeneic haematopoietic stem cell transplantation, patients microbiomes were sampled at the time of acute (aGVHD) onset and compared with 35 post-transplant individuals without GVHD. Interestingly, specific microbiome signatures were associated with gastrointestinal aGVHD severity.…”

“… 34 Overall, many factors may explain the noted inconsistencies between studies including differences in the studied populations (eg, genetics, diet, geography, control comparison group) and methodologic variability in profiling microbiome composition. For example, the two Behcet’s studies were conducted in different geographic locations, that is, Italy 7 and Japan, 33 making comparisons between studies challenging due to the potential for confounding variables.…”

Findings on the Relationship Between Intestinal Microbiome and Vasculitis

“…Some cross-sectional studies have reported that gut bacterial abundance changes in BD patients compared with healthy controls ( Table 3 ) ( Consolandi et al., 2015 ; Shimizu et al., 2016 ; Ye et al., 2018 ; Oezguen et al., 2019 ; Shimizu et al., 2019 ; Bilge et al., 2020 ; Tecer et al., 2020 ; van der Houwen et al., 2020 ; Kim et al., 2021 ). These results showed that the gut microbiota in BD patients was enriched with lactic acid-producing bacteria, sulfate-reducing bacteria, and some opportunistic pathogens but lacked butyric acid-producing bacteria and methanogenic bacteria.…”