title: Reduced protein bound uraemic toxins in vegetarian kidney failure patients treated by haemodiafiltration.
abstract: Introduction Indoxyl sulfate (IS) and p cresyl sulfate (PCS) are protein bound toxins which accumulate with chronic kidney disease. Haemodiafiltration (HDF) increases middle molecule clearances and has been suggested to increase IS and PCS clearance. We therefore wished to establish whether higher convective clearances with HDF would reduce IS and PCS concentrations. Methods We measured total plasma IS and PCS in a cohort of 138 CKD5d patients treated by On-line HDF (Ol-HDF), by high pressure liquid chromatography. Findings Mean patient age was 64.6 ± 16.5 years, 60.1% male, 57.3% diabetic, median dialysis vintage 25.9 months (12.4-62.0). The mean ICS concentration was 79.8 ± 56.4 umol/L and PCS 140.3 ± 101.8 umol/L. On multivariate analysis, IS was associated with serum albumin (β 4.31,P < 0.001), and negatively with residual renal function (β-4.1,P = 0.02) and vegetarian diet(β-28.3, P = 0.048) and PCS negatively with log C reactive protein (β-75.8, P < 0.001) and vegetarian diet (β-109, P = 0.001). Vegetarian patients had lower IS and PCS levels (median 41.5 (24.2-71.9) vs. 78.1 (49.5-107.5) and PCS (41.6 (14.2-178.3) vs. 127.3 (77.4-205.6) µmol/L, respectively, P < 0.05. Vegetarian patients had lower preOl-HDF serum urea, and phosphate (13.8 ±3.8 vs. 18.4 ± 5.2 mmol/L, and 1.33 ± 0.21 vs. 1.58 ± 0.45 mmol/L), and estimated urea nitrogen intake (1.25 ± 0.28 vs. 1.62 ± 0.5 g/kg/day), respectively, all P < 0.05. Discussion Plasma IS and PCS concentrations were not lower with Ol-HDF compared to previous studies in haemodialysis patients. However those eating a vegetarian diet had reduced IS and PCS concentrations. Although this could be due to differences in dietary protein intake, a vegetarian diet may also potentially reduce IS and PCS production by the intestinal microbiome.
authors.affiliation: UCL Centre for Nephrology, Royal Free Hospital, University College London Medical School, London, UK.
authors.forename: Sakina
authors.initials: S
authors.lastname: Kandouz
authors.affiliation: ISN/UKRA fellow, UCL Centre for Nephrology, Royal Free Hospital, University College London Medical School, London, UK.|Zagazig University, Markaz El-Zakazik, Ash Sharqia Governorate, 44516, Egypt.
authors.forename: Ali Shendi
authors.initials: AS
authors.lastname: Mohamed
authors.affiliation: Department of Pharmacy & Biomolecular Sciences, Brighton University, Brighton, UK.
authors.forename: Yishan
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Department of Pharmacy & Biomolecular Sciences, Brighton University, Brighton, UK.
authors.forename: Susan
authors.initials: S
authors.lastname: Sandeman
authors.affiliation: UCL Centre for Nephrology, Royal Free Hospital, University College London Medical School, London, UK. andrewdavenport@nhs.net.
authors.forename: Andrew
authors.initials: A
authors.lastname: Davenport
mesh_terms: D005260:Female; D017583:Hemodiafiltration / Q000379:methods*; D006801:Humans; D007200:Indican / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis / Q000379:methods*; D051436:Renal Insufficiency, Chronic / Q000628:therapy*; D014508:Urea / Q000097:blood*; D000066988:Vegetarians
chemical_list: D014508:Urea; D007200:Indican
keywords: Indoxyl sulfate; haemodiafiltration; p cresyl sulfate; residual renal function; vegetarian