Does Indoxyl Sulfate Have a Role in Uremic Pruritus? A Laboratory and Interventional Study

Abstract

Background: Pruritus is a common complaint in patients with end-stage renal disease. Indoxyl sulfate (IS) is a tryptophan end metabolite extremely renal excreted. Activated charcoal can interfere with IS intestinal absorption. Objectives: To evaluate the serum level of IS and the effect of activated charcoal on uremic pruritus. Materials and Methods: In all, 135 participants were divided into 2 main groups. In total, 45 normal and healthy individuals as a control group and 90 patients on regular hemodialysis; 45 of these patients had uremic pruritus and the other 45 were not complaining of uremic pruritus. Serum IS was measured. Activated charcoal was used by patients with uremic pruritus. The severity of pruritus and Dermatology Life Quality Index (DLQI) were assessed. Results: The serum IS was significantly elevated in uremic patients than in control subjects ( P < .001) and significantly elevated in uremic patients without pruritus ( P < .001). Furthermore, there were positive significant correlations between the serum IS and both severity of pruritus ( P < .001) and DLQI ( P < .001). After activated charcoal usage, there was a significant decrease in IS level with the improvement of pruritus and quality of life of patients. Conclusions: IS may play a role in uremic pruritus. Activated charcoal could be considered a treatment for uremic pruritus.