Renal Bx congenital NS of the Finnish type - tubular changes

Renal biopsy from an infant with congenital nephrotic syndrome (NS) of the Finnish type due to mutations in the NPHS1 gene that encodes nephrin, a transmembrane protein located at the slit diaphragm of the glomerular podocytes. The most striking histologic finding is the irregular microcystic dilatation of proximal tubule.