Abstract: SA-PO161

Effect of Fructooligosaccharide on Microbiota-Derived Uremic Toxins in Predialysis Patients: A Randomized Controlled Trial

Session Information

Category: Nutrition, Inflammation, and Metabolism

  • 1401 Nutrition, Inflammation, Metabolism


  • Ramos, Christiane Ishikawa, Federal University of Sao Paulo, Sao Paulo, Brazil
  • Armani, Rachel Gatti, Federal University of Sao Paulo, Sao Paulo, Brazil
  • Nakao, Lia S., Federal University of Parana, Curitiba, Brazil
  • Canziani, Maria Eugenia F., Federal University of Sao Paulo, Sao Paulo, Brazil
  • Campbell, Katrina L., Princess Alexandra Hospital, Brisbane, New South Wales, Australia
  • Cuppari, Lilian, Federal University of Sao Paulo, Sao Paulo, Brazil

Microbiota-derived uremic toxins, p-cresyl sulfate (PCS) and indoxyl sulfate (IS), have been associated with poor outcomes in chronic kidney disease (CKD). This has encouraged the investigation of alternative approaches to modulate gut environment and to attenuate toxin production. The present trial aimed to evaluate the effect of the prebiotic fructooligosaccharide (FOS) on changes in PCS, IS, indole 3-acetic acid (IAA), kidney damage (eGFR and proteinuria) and insulin resistance in predialysis patients (stages 3b, 4 and 5).


The 3-month double-blind randomized controlled trial included 46 non-diabetic CKD patients [52% men; 57.6±14.4 years; eGFR: 21.3±7.3 mL/min/1.73m2]. Intervention and placebo consisted in 12g/day of FOS or maltodextrin, respectively. PCS, IS and IAA were determined by high performance liquid chromatography. Dietary intake was assessed by 3-day food records; supplement adherence (sachet count) and gastrointestinal events by the Gastrointestinal Symptom Rating Scale.


Aside for the intervention group being older (53.4±16.0 vs 61.9±11.4 years, p=0.04) the groups were homogeneous. Overall sachet adherence was excellent (mean consumption: 93.1±8.1%). No changes in the ratio of dietary protein/fibre intake or gastrointestinal symptoms were observed during the follow-up. Changes in the outcomes are depicted in the table.


FOS was well tolerated and resulted in a trend for reduced PCS. No effect of FOS on IS, IAA, kidney damage or insulin resistance was observed.

Treatment effect
Mean [95% CI]
PCS (mg/L)1.3±24.6-12.3±25.1-13.5[-29.2–2.3]*0.09*
IS (mg/L)-0.2(-1.5–1.8)-0.2(-0.9–1.0)-0.1[-1.6–1.4]0.90
IAA (µM/L)-0.7(1.8–1.0)0.1(-1.7–1.6)1.8[-4.4–8.1]0.44
eGFR (ml/min/1.73m2)0.2±2.80.2±3.40.6[-3.7–5.0]1.00
Proteinuria (mg/24hr)70.0(-130.0–620.0)80.0(-130.0–620.0)1.2[-0.6–3.0]0.78

Mean±sd or median (interquartile range). CI: confidence interval. *Adjusted by baseline PCS, dietary protein/fibre ratio and age.


  • Government Support - Non-U.S.