Intestinal permeability in patients with IgA nephropathy and other glomerular diseases: an observational study

J Nephrol. 2023 Mar;36(2):463-474. doi: 10.1007/s40620-022-01454-2. Epub 2022 Sep 15.

Abstract

Background: A dysregulated 'gut-kidney axis' may contribute to immunoglobulin A nephropathy (IgAN). We studied whether IgAN patients have disturbed intestinal permeability.

Methods: In a prospective, cross sectional, pilot study we assessed intestinal permeability in 35 IgAN patients, 18 patients with non-IgAN glomerulonephritides (GNs) and 19 healthy controls. After an overnight fast, trial participants ingested a multi-sugar solution and samples were obtained from 0 to 2, 2 to 5- and 5 to 24-h urine portions. Urinary sugar concentrations were quantified using isocratic ion-exchange high performance liquid chromatography. Indices of small intestinal permeability (0-2-h lactulose/L-rhamnose (L/R) ratio), distal small intestinal and proximal colonic permeability (2-5-h sucralose/erythritol (S/E) ratio) and colonic permeability (5-24-h sucralose/erythritol (S/E) ratio) were evaluated. Associations between groups and indices of intestinal permeability were investigated by a linear mixed model.

Results: Small intestinal permeability (0-2 h L/R-ratio) was significantly increased in patients with glomerular diseases versus healthy controls. More precisely, increased small intestinal permeability was exclusively noted in non-IgAN GN patients, whereas IgAN patients exhibited a trend towards elevated small intestinal permeability. In total, 54% of patients with IgAN and 67% of non-IgAN GN patients had increased small intestinal permeability. Neither distal small intestinal and proximal colonic permeability nor colonic gut permeability indices (i.e., 2-5 h and 5-24 h S/E ratios) were significantly different between controls and any of the GN patient groups.

Conclusion: The present single center pilot study suggests that disturbed intestinal permeability is common in patients with glomerular diseases and is not specific for IgAN.

Trial registration number: German Clinical Trials Register DRKS00021533, Date: 24.04.2020.

Keywords: Gut-kidney axis; IgA nephropathy; Intestinal permeability; Multi sugar test.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cross-Sectional Studies
  • Erythritol
  • Glomerulonephritis, IGA*
  • Humans
  • Permeability
  • Pilot Projects
  • Prospective Studies
  • Rhamnose

Substances

  • Rhamnose
  • Erythritol

Associated data

  • DRKS/DRKS00021533