Relationship between plasma Cystatin C and creatinine in chronic renal diseases and Tx-transplant patients.
OBJECTIVE
Glomerular filtration rate (GFR) is the best overall index of renal function in health and disease. Recently, Cystatin C (Cyst C), a low molecular weight protein freely filtered through the glomerulus, and almost completely reabsorbed and catabolized by tubular cells, has been proposed as a new and very sensitive serum marker of change in GFR. This study investigated the relationship between Cyst C and creatinine (CR) in renal disease patients.


METHODS
Serum Cyst C was determined by particle-enhanced immunoturbidimetry using the Cyst C PET-kit. The results could be obtained within 1 h. Cuvettes were washed before the Cyst C assay as recommended. Serum CR, BUN and albumin were determined by auto-analyzer.


RESULTS
A strong correlation was observed between Cyst C and CR (P = 0.001, r = 0.764 and P = 0.0001, r = 0.888, respectively) in prehemodialysis (pre-HD) and kidney transplantation (Tx-kidney), whereas there was a weak correlation in continuous ambulatory peritoneal dialysis (CAPD) (P = 0.05, r = 0.535).


CONCLUSIONS
These findings suggest that serum Cyst C may be considered as a sensitive predictive parameter for reduced GFR. It is of value for the laboratory diagnosis of chronic renal failure and should be preferentially used for CR clearance.
Gökkuşu
Cahide Anil
CA
Department of Biochemistry, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey. cahgok@istanbul.edu.tr
Ozden
Tülin Ayse
TA
Gül
Hülya
H
Yildiz
Alattin
A
D000328:Adult; D015415:Biomarkers; D003404:Creatinine / Q000097:blood*; D055316:Cystatin C; D015891:Cystatins / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000628:therapy; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D010531:Peritoneal Dialysis, Continuous Ambulatory; D006435:Renal Dialysis
D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C; D015891:Cystatins; D003404:Creatinine