Urinary transforming growth factor-β1 in children with obstructive uropathy

Aim: Obstructive uropathies (OU) in childhood constitute one of the major causes of chronic renal insufficiency. Transforming growth factor-beta 1 (TGF-beta 1) is considered to be the major fibrogenic growth factor. The aim of the present study was to investigate urinary TGF-beta 1 levels in children with obstructive and non-obstructive uropathies (NOU). Methods: This study involved 19 children with OU, 11 children with non-obstructive hydronephrosis and 21 healthy children. Urinary TGF-beta 1, proteinuria, microalbuminuria and urinary alpha 1-microglobulin were measured, and renal function was assesed. The results were statistically analyzed. Results: Mean urinary TGF-beta 1 concentrations in patients with OU were significantly higher than those with NOU (4.14 +/- 0.67 creatinine vs 1.80 +/- 1 0.24 pg/mmol creatinine, P < 0.05) and healthy controls (1.66 +/- 0.28 pg/mmol creatinine, P < 0.05). Positive correlations of urinary TGF-beta 1 concentrations with proteinuria (r = 0.87, P < 0.0001) and urinary alpha 1-microglobulin (r = 0.82, P = 0.0002) were found in patients with OU. Conclusion: Children with OU have higher urinary TGF-beta 1 than children with NOU. Urinary TGF-beta 1 may be a useful non-invasive tool for the differential diagnosis between OU and NOU in children. A positive correlation of TGF-beta 1 with markers of renal tissue damage in patients with OU was found.