Urinary excretion of podocyte dysfunction markers in patients with chronic glomerulonephritis

Background. Recent studies have highlighted that podocyte (Pdc) injury leads to proteinuria (PU) and glomerulosclerosis. Urinary detection of Pdc injury markers is widely discussed as more sensitive indicators of chronic glomerulonephritis (СGN) activity and prognosis than PU. The aim of our study was to define nephrinuria (NU) and vascular endothelial growth factor (VEGF) excretion for an assessment of CGN activity and therapy efficiency. Methods. 74 CGN pts were studied: 18 – inactive CGN (I group), 18 – with PU 1-3 g/d (II), 38 – with nephrotic syndrome (NS) (III). 12 healthy subjects were studied as control. NU and urinary VEGF were measured by ELISA. Results: We revealed significantly increased NU and VEGF in active CGN (II, III group) compared to I group and control. These levels were greatly higher in NS than in pts with lower PU. NU depended on NS duration. Positive correlations were revealed between NU and PU value (r=0,27 p<0,05) and mean blood pressure (r=0,3 p=0,032). Urinary VEGF level was the highest in NS without renal failure. In pts with NS and impaired renal function we revealed significantly decreased urinary VEGF. 9 from 11 (82%) pts with low NU (<17ng/ml) had NS remission during 6 month of immunosuppressive therapy. On the other hand, 8 from 12 (67%) pts with high NU (>17ng/ml) had the immunosuppression resistance (9 month to 2 years). Conclusion: We suggest that estimation of NU and VEGF urinary levels may be useful for glomerular damage monitoring, CGN risk progression assessment and treatment efficiency prognosis.

хронический гломерулонефрит, протеинурия, повреждение подоцитов, нефринурия, экскреция с мочой VEGF, подоцитопения, гломерулосклероз, chronic glomerulonephritis, proteinuria, podocytes damage, nephrinuria, urinary excretion of VEGF, podocytopenia, glomerulosclerosis

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