Microbiome analysis reveals that Ralstonia is responsible for decreased renal function in patients with ulcerative colitis

Abstract

Microbiome analysis reveals that Ralstonia is responsible for decreased renal function in patients with ulcerative colitis Dear Editor, The causal link between inflammatory bowel disease (IBD) and chronic kidney disease (CKD) is not clear; therefore , we aimed to investigate the role of gut microbiota in decreasing renal function in patients with IBD. IBD is characterized by the disruption of host-microbe relationships , and dysbiosis and the metabolites produced by the dysbiotic intestinal microbiome may negatively influence the renal function. 1 Indeed, epidemiological studies have shown that the prevalence of CKD is higher in individuals with ulcerative colitis (UC) compared to those without UC. 2,3 To reveal the connection between UC and CKD, we performed 16S ribosomal DNA sequencing using ileoce-cal mucosal samples from nine patients with both UC and CKD, 29 UC patients with normal renal function, and 12 healthy individuals who had normal colonoscopy results (Table S1; Figure S1). The patients with CKD showed estimated glomerular filtration rate (eGFR) values less than 60 mL/min/1.73 m 2 for a minimum of 3 months. The bacterial operational taxonomic units of patients in the UC + CKD group were decreased but were not significantly different from those of the UC or control group (Fig-ure S2A>). Community richness, such as the Chao1 index and abundance-based coverage estimator (ACE), was not different among the three groups (Figure S2B and C). However , the Shannon diversity index and the inverse Simp-son diversity index were significantly decreased in the UC+CKD group compared to that in the control or UC group (Figure S2D and E), suggesting that the bacterial diversity was lower in the UC + CKD group. Additionally, eGFR was significantly positively correlated with the Shan-non index and the inverse Simpson index (Table S2). The principal component analysis showed an overlap to some extent among the three groups, indicating similar bacterial community structures (Figure S2F). Among six bacterial phyla which accounted for over 97% of taxonomy in the gut microbiota of the study population, Actinobacteria exhibited the highest relative abundance in This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.