title: Relationship between plasma Cystatin C and creatinine in chronic renal diseases and Tx-transplant patients.
abstract: 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.
authors.affiliation: Department of Biochemistry, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey. cahgok@istanbul.edu.tr
authors.forename: Cahide Anil
authors.initials: CA
authors.lastname: Gökkuşu
authors.forename: Tülin Ayse
authors.initials: TA
authors.lastname: Ozden
authors.forename: Hülya
authors.initials: H
authors.lastname: Gül
authors.forename: Alattin
authors.initials: A
authors.lastname: Yildiz
mesh_terms: 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
chemical_list: D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C; D015891:Cystatins; D003404:Creatinine