J Wang1, R Konda, H Sato, K Sakai, S Ito, S Orikasa. 1. Department of Urology and Second Department of Internal Medicine, Tohoku University School of Medicine, Sendai, Japan.
Abstract
PURPOSE: We determined urinary interleukin-6 (IL-6) in children with reflux nephropathy to evaluate the clinical significance of this cytokine in the progression of renal injury. MATERIALS AND METHODS: Enrolled in this study were 34 boys and 32 girls in whom 99mtechnetium dimercapto-succinic acid renal scan showed renal scarring. Vesicoureteral reflux had been corrected surgically at least 3 years before study entry. Urinary IL-6 was determined by enzyme-linked immunosorbent assay using spot urine samples. Simultaneously we measured serum creatinine, beta2-microglobulin, alpha1-microglobulin, urinary alpha1-microglobulin and albumin. In addition, IL-6 expression was assessed by immunohistochemical study in the scarred kidneys of 3 boys and 1 girl who underwent nephrectomy due to severe reflux nephropathy with little function on renal scan. RESULTS: Urinary IL-6 was significantly higher in children with severe bilateral renal scarring than in those with mild scarring and normal controls. Urinary IL-6 correlated significantly with serum alpha1-microglobulin (Spearman test p <0. 03), beta2-microglobulin (p <0.003), creatinine (p <0.02) and urinary albumin (p <0.0001). Histological evaluation revealed that IL-6 was predominantly expressed in the tubules in and adjacent to fibrotic areas. CONCLUSIONS: Our observations indicate that tubular IL-6 may be involved in the pathogenesis of tubulointerstitial injury in reflux nephropathy and urinary IL-6 may be a useful tool for monitoring the progression of reflux nephropathy.
PURPOSE: We determined urinary interleukin-6 (IL-6) in children with reflux nephropathy to evaluate the clinical significance of this cytokine in the progression of renal injury. MATERIALS AND METHODS: Enrolled in this study were 34 boys and 32 girls in whom 99mtechnetium dimercapto-succinic acid renal scan showed renal scarring. Vesicoureteral reflux had been corrected surgically at least 3 years before study entry. Urinary IL-6 was determined by enzyme-linked immunosorbent assay using spot urine samples. Simultaneously we measured serum creatinine, beta2-microglobulin, alpha1-microglobulin, urinary alpha1-microglobulin and albumin. In addition, IL-6 expression was assessed by immunohistochemical study in the scarred kidneys of 3 boys and 1 girl who underwent nephrectomy due to severe reflux nephropathy with little function on renal scan. RESULTS: Urinary IL-6 was significantly higher in children with severe bilateral renal scarring than in those with mild scarring and normal controls. Urinary IL-6 correlated significantly with serum alpha1-microglobulin (Spearman test p <0. 03), beta2-microglobulin (p <0.003), creatinine (p <0.02) and urinary albumin (p <0.0001). Histological evaluation revealed that IL-6 was predominantly expressed in the tubules in and adjacent to fibrotic areas. CONCLUSIONS: Our observations indicate that tubular IL-6 may be involved in the pathogenesis of tubulointerstitial injury in reflux nephropathy and urinary IL-6 may be a useful tool for monitoring the progression of reflux nephropathy.
Authors: Mariana A Vasconcelos; Maria Candida F Bouzada; Katia D Silveira; Leticia R Moura; Fabiana F Santos; Juliana M Oliveira; Flavia F Carvalho; Mauro M Teixeira; Ana Cristina Simões E Silva; Eduardo A Oliveira Journal: Pediatr Nephrol Date: 2011-02-18 Impact factor: 3.714