Urinary levels of TGF β-1 and of cytokines in patients with prenatally detected nephrouropathies

Abstract

This study aimed to identify noninvasive biomarkers of clinically significant nephrouropathies in patients with antenatal renal and/or urinary tract alterations. Spot-urine levels of interleukin-6 (IL-6), transforming growth factor-β1 (TGF-β1) and tumor necrosis factor-α (TNF-α) were measured in 100 patients with antenatal detected nephrouropathies. Patients were divided in idiopathic hydronephrosis (n = 47), urinary tract malformations (n = 35), and dysplastic kidneys (n = 18). Urinary concentrations of TGF-β1, IL-6, and TNF-α were compared between groups according to clinical and image findings. Receiver-operating characteristic (ROC) curves were analyzed for the overall diagnostic accuracy of TGF-β1, IL-6, and TNF-α levels in discriminating infants with nephrouropathies. No significant differences in urinary TGF- β1, IL-6, and TNF-α levels were found in the comparison between the groups. TGF-β1 levels tended to be higher in patients with renal hypodysplasia compared to idiopathic hydronephrosis (p = 0.07). Twenty-nine patients had reduced DMSA uptake. In these cases, absolute urinary concentration of TGF-β1 and levels standardized for creatinine were significantly higher than in patients with normal DMSA uptake, while IL6 and TNF-α did not differ between groups. Urinary cytokine measurements were not useful as a screening test for clinically significant nephrouropathies. Conversely, increased concentrations of TGF-β1 pointed out to renal damage as indicated by reduced DMSA uptake.