PS-C13-7: THE ROLE OF WATER HAMMER PRESSURE IN THE GLOMERULAR PODOCYTE SHEDDING AND RENAL PROGNOSIS

Objective: Urinary podocyte excretion is related to a reduction in glomerular podocyte numbers, glomerulosclerosis, and urinary protein selectivity. To elucidate the factors of urinary podocyte shedding and renal prognosis, we examined urinary podocytes in 120 renal biopsy patients. Design and method: Podocytes were identified in urinary sediments stained with fluorescent-labelled anti-podocalyxin antibodies in ten high power fields. The amounts of protein bands, separated by SDS-polyacrylamide gel electrophoresis, were calculated using an image software program. The renal prognosis, including induction of hemodialysis or 30% reduction in eGFR, was investigated. Results: Urinary podocyte excretion showed a higher positive correlation with albumin excretion compared to IgG, prealbumin, and transferrin, but not with low molecular weight proteins, including beta2-microglobulin and alpha1-microglobulin. The hemodynamic pressure on the glomerular capillary wall, including products of pulse pressure and pulse rate (water hammer pressure), was positively correlated with urinary podocyte excretion. Urinary podocyte excretion and Tamm-Horsfall protein were independent risk factors for renal prognosis. Conclusions: Urinary podocytes shed from glomerular capillaries by water hammer and were involved in albuminuria and renal prognosis of renal biopsy patients.