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The following is a summary of “Development of a multiple urinary biomarker model to predict the tubulointerstitial fibrosis area in patients with primary IgA Nephropathy,” published in the March 2025 issue of BMC Nephrology by Rodríguez et al. 

Previous studies showed that urinary biomarkers help predict interstitial fibrosis in IgA Nephropathy. The most accurate biomarker or combination remains unclear. 

Researchers conducted a retrospective study measuring seven urinary tubular injury biomarkers in patients with primary IgA Nephropathy to assess their utility as non-invasive estimators of interstitial fibrosis area on kidney biopsy. 

They included 247 adults with primary IgA Nephropathy and 50 healthy controls, measuring urinary EGF, MCP-1, NGAL, KIM-1, L-FABP, β2-microglobulin, and DKK-3 from biopsy-day urine samples. The estimated glomerular filtration rate was calculated using the CKD-EPI formula, while interstitial fibrosis area was quantified morphometrically, graded per Oxford Classification, and analyzed using predictive multivariate models. 

The results showed that patients with primary IgA Nephropathy had higher urinary DKK-3, L-FABP, and β2-microglobulin and lower EGF than healthy controls. Interstitial fibrosis was negatively correlated with urinary EGF and positively with age, proteinuria, eGFR, DKK-3, L-FABP, and β2-microglobulin. The best model predicted >60% of fibrosis variability and included age, eGFR, proteinuria, DKK-3, EGF, L-FABP, and β2-microglobulin. 

Investigators developed a model to estimate interstitial fibrosis in IgA Nephropathy, which was useful for monitoring chronic kidney injury progression. 

Source: bmcnephrol.biomedcentral.com/articles/10.1186/s12882-025-04049-8