Intestinal microbiota profile and inflammation in patients undergoing hemodialysis: a comparison between the Southern and Southeastern regions of Brazil

Exogenous lifestyle factors, such as different cultures, diets, and geo-graphic location, can alter the microbiota in patients with chronic kidney disease (CKD), which is closely related to inflammation. However, few studies have examined how these factors influence the composition of the microbiota. Thus, the objective of this study was to characterize and compare the intestinal microbiota profile and inflammation in CKD patients undergoing hemodialysis (HD) in the Southern and Southeastern regions of Brazil.

Blood and stool samples were obtained from two groups of HD patients: one from the city of Blumenau (Southern region) and the other from the city of Rio de Janeiro (Southeastern region). Fecal DNA was extracted, and the V4 region of the bacterial 16S ribosomal RNA gene was sequenced. The fecal microbiome was analyzed using bioinformatic tools. Plasma concentrations of IL-6 and TNF-α were evaluated by ELISA.

Thirty patients were included in the study, with 14 individuals residing in the Southern region (group S) [50% male, 58 (13.5) years of age] and 16 individuals residing in the Southeastern region (group SE) [47.1% male, 57 (19) years of age]. The α- and β-diversity indices of the intestinal microbiota did not differ significantly between the groups. However, patients from the Southern region had higher plasma TNF-α (p = 0.008) and IL-6 (p = 0.003) levels than those from the Southeastern region.

Although HD patients with CKD residing in the Southern and Southeastern regions present similar intestinal microbial patterns, patients from the Southern region had higher concentrations of inflammatory markers.