Is serum Cystatin-C a suitable marker of renal function in children?
Cystatin C (Cys-C) is a low-molecular weight (13 kDa) protein that is a member of the cysteine protease family and is produced by all nucleated cells. In normal conditions, serum Cys-C is almost completely filtered by the renal glomerulus and largely catabolized by proximal tubular cells. Since serum Cys-C levels are closely correlated with the glomerular filtration rate (GFR), serum Cys-C assay has been introduced as a marker of renal function in patients with kidney diseases. In this review, we focus on studies reported during the past decade in which serum Cys-C levels have been compared to serum creatinine levels as a marker of GFR in pediatric populations. All but one of these studies showed diagnostic superiority or equivalence of serum Cys-C levels vs serum creatinine levels in children. The recent evidence from clinical trials generally supports the use of serum Cys-C assays as a renal function test in pediatric patients. However, clinicians should be cognizant of extrarenal conditions and pharmacological factors that can influence the results of serum Cys-C assays.
Zaffanello
Marco
M
Department of Mother-Child and Biology-Genetics, University of Verona, Piazzale L Scuro 10, Verona, Italy. marco.zaffanello@univr.it
Franchini
Massimo
M
Fanos
Vassilios
V
D000293:Adolescent; D015415:Biomarkers / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D055316:Cystatin C; D015891:Cystatins / Q000097:blood*; D006801:Humans; D007223:Infant; D007674:Kidney Diseases / Q000097:blood*; D007677:Kidney Function Tests / Q000379:methods*; D010372:Pediatrics / Q000379:methods; D011480:Protease Inhibitors / Q000097:blood*
D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C; D015891:Cystatins; D011480:Protease Inhibitors