[Serum indoxyl sulfate is a useful predictor for progression of chronic kidney disease].
BACKGROUND
Indoxyl sulfate, an endogenous metabolite of tryptophan is normally excreted into urine. In patients with chronic kidney disease (CKD), however, the reduced indoxyl sulfate renal clearance leads to elevated indoxyl sulfate serum level. In this study we determined whether the serum levels of indoxyl sulfate are related to the progression rate of CKD stage in CKD patient.


METHODS
The association between indoxyl sulfate and progression of CKD stage was studied in 47 CKD patients (19 male, 28 female). Serum levels of IS were measured by using high performance liquid chromatography and the measured values of the study cohort were divided into quintiles.


RESULTS
The mean serum amount indoxyl sulfate in the healthy subject was 0.06 +/- 0.04 mg/dL (mean +/- SD). Those with indoxyl sulfate serum levels of > or = 0.3 mg/dL had a significantly progression of CKD than with <0.3 mg/dL. Especially, those patients with indoxyl sulfate serum levels of 0.47 mg/dL had the highest CKD progression.


CONCLUSIONS
High serum levels of indoxyl sulfate are related with a progression of CKD stage in CKD patients. Thus, serum indoxyl sulfate is one of the clinical factors that affect CKD progression.
Namba
Shunji
S
Department of Clinical Laboratory, Toho University Omori Medical Center, Ota-ku, Tokyo 143-8541, Japan. namba@med.toho-u.ac.jp
Okuda
Yuko
Y
Morimoto
Akiko
A
Kojima
Tetsumi
T
Morita
Toshisuke
T
D000368:Aged; D015415:Biomarkers / Q000097:blood; D002908:Chronic Disease; D018450:Disease Progression; D005260:Female; D006801:Humans; D007200:Indican / Q000097:blood*; D007674:Kidney Diseases / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests
D015415:Biomarkers; D007200:Indican