OBJECTIVE: To examine whether (1) levels of urinary kidney injury molecule-1 (KIM-1), a transmembrane protein and biomarker for renal tubular damage, increase in children with of vesicoureteral reflux (VUR), and (2) if KIM-1 predicts the grade of renal scarring in children with VUR.
METHODS: The study included 59 VUR patients with renal scarring, 5 VUR patients without renal scarring and 25 healthy controls aged 1 to 17 years. Dimercaptosuccinic acid scans were performed for determination of scarring and graded by 3 independent, blinded pediatric urologists for renal scarring according to the Randomized Intervention for Children with VUR study criteria. Spot urine samples were obtained. Urinary KIM-1 and creatinine levels were measured and the KIM-1/creatinine ratio was calculated.
RESULTS: Urine geometric mean KIM-1 levels (ng/mg creatinine) were significantly higher in VUR patients than in healthy controls (P=.018). Although the correlation between VUR grade and geometric mean KIM-1 levels was not significant, a positive correlation was found for scarring grade and geometric mean KIM-1 levels (r=.30, P=.02). When the patients were divided by subgroups according to scarring grade (group I, grade 1; group II, grades 2 and 3; group III, grade 4), the log KIM-1 in group III was significantly higher than in group I (P=.004).
CONCLUSION: Urinary KIM-1 levels might be used as a noninvasive marker, particularly in showing severe scarring in children with VUR.
Written by:
Toker A, Ziypak T, Orsal E, Laloglu E, Bedir F, Aksoy Y. Are you the author?
Department of Biochemistry, Meram Medical Faculty, Necmettin Erbakan University, Konya, Turkey.
Reference: Urology. 2013 Jan;81(1):168-72.
doi: 10.1016/j.urology.2012.09.004
PubMed Abstract
PMID: 23200959
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