Excretion Patterns of Urinary Sediment and Supernatant Podocyte Biomarkers in Patients with CKD

BACKGROUND: Podocyte depletion causes glomerulosclerosis, and persistent podocyte loss drives progression to ESKD. Urinary sediment podocin (u-sed Pod) mRNA excretion and urinary supernatant podocalyxin (u-sup PCX) protein have been used to monitor disease activity in glomerular diseases. However, the differences in these markers among pathologies have not been investigated. We examined the roles of these markers in kidney diseases. METHODS: From January 2013 to March 2016, early morning urine samples were collected from 12 healthy controls and 172 patients with kidney disease (n=15 patients with minor glomerular abnormality with mild proteinuria and/or microscopic hematuria, n=15 with minimal change nephrotic syndrome [MCNS], n=15 with membranous nephropathy [MN], n=60 with IgA nephropathy [IgAN], n=19 with crescentic GN [Cres GN], n=10 with lupus nephritis [LN], and n=38 with other kidney diseases). We examined u-sed Pod mRNA excretion, u-sup PCX protein, and the urinary protein-creatinine ratio (u-PCR). RESULTS: u-sed Pod mRNA excretion was significantly correlated with u-sup PCX protein (r=0.37, P