Urinary DKK3 as a predictor of CKD stages in reflux nephropathy in children.

BACKGROUND/AIM: Reflux nephropathy is an important cause of chronic kidney disease (CKD) in children. The search for new biomarkers continues, as early intervention is important to slow the progression of CKD. Urinary Dickkopf-3 (uDKK3), a potential marker of tubulointerstitial fibrosis, has been studied in adults but not extensively in children with CKD. This study was conducted to determine the role of uDKK3 levels in predicting the CKD stage in children with reflux nephropathy.

MATERIALS AND

METHODS

This cross-sectional study included 113 children with CKD stages 1-4 with reflux nephropathy and 28 healthy controls. uDKK3 concentrations were measured using enzyme-linked immunosorbent assay. The association between uDKK3, the estimated glomerular filtration rate (eGFR), and albuminuria was investigated. Receiver operating characteristic (ROC) curves were used to assess diagnostic performance.

RESULTS

uDKK3 levels were significantly higher in CKD stages 3 and 4 compared to stages 1 and 2 and the control group. A strong negative correlation was observed between uDKK3 and the eGFR, while a positive correlation was noted with albuminuria. ROC analysis revealed an area under the curve (AUC) of 0.77 for the uDKK3 to urinary Cr (uCr) ratio (uDKK3/uCr), with a sensitivity of 71.1% and a specificity of 71.4% at a cutoff value of 1675.48 pg/mg.

CONCLUSION

The correlation between the uDKK3/uCr and CKD severity suggests that uDKK3 may serve as a potential noninvasive biomarker for assessing disease severity. However, its utility for identifying early-stage CKD could not be clearly demonstrated in this cohort. uDKK3 appears to be particularly associated with advanced CKD stages, and further large-scale prospective studies are needed to clarify its clinical applicability and prognostic value in pediatric CKD.