Serum Total p -Cresol and Indoxyl Sulfate Correlated With Stage of Chronic Kidney Disease in Renal Transplant Recipients

Abstract Background Uremic toxins are considered cardiovascular and mortality risk factors in chronic kidney disease (CKD) patients. Both p -cresol and indoxyl sulfate have been shown to induce oxidative stress in vitro and subsequent endothelial dysfunction in uremic patients. Our study evaluated the levels of p -cresol and indoxyl sulfate, and whether they contribute to the progression of CKD in transplant recipients. Methods We retrospectively evaluated 95 patients who had received a transplant from February 1987 to June 2010 in our center; the recipients had a mean transplant duration of 5.3 ± 4.9 years and a mean age of 47.8 ± 14.1 years. Among them, 56.8% (54/95) were male. Patients with glomerular filtration rate (GFR) ≥ 60 mL/min/1.73 m2 were selected for group 1 (n = 35), and those with GFR < 60 mL/min/1.73 m2 were selected for group 2 (n = 60). Demographic and clinical data were compared between groups. Serum and urine levels of p -cresol and indoxyl sulfate were also obtained. Results Baseline serum p -cresol and indoxyl sulfate levels were significantly higher in advanced CKD stages ( P = .001 and