The most common NPHS1 gene mutations, Fin-major and Fin-minor, both lead to an absence of nephrin and podocyte slit diaphragms, as well as a clinically severe form of NPHS1, the Finnish type of congenital nephrotic syndrome.

No abstract

Nephrin is a cell adhesion protein located at the slit diaphragm area of glomerular podocytes. Mutations in nephrin-coding gene (NPHS1) cause congenital nephrotic syndrome (NPHS1). We studied the developmental expression of nephrin, ZO-1 and P-cadherin in normal fetal kidneys and in NPHS1 kidneys. We used in situ hybridization and immunohistochemistry at light and electron microscopic levels. Nephrin and zonula occludens-1 (ZO-1) were first expressed in late S-shaped bodies. During capillary loop stage, nephrin and ZO-1 localized at the basal margin and in the cell-cell adhesion sites between developing podocytes, especially in junctions with ladder-like structures. In mature glomeruli, nephrin and ZO-1 concentrated at the slit diaphragm area. P-cadherin was first detected in ureteric buds, tubules, and vesicle stage glomeruli. Later, P-cadherin was seen at the basal margin of developing podocytes. Fetal NPHS1 kidneys with Fin-major/Fin-major genotype did not express nephrin, whereas the expression of ZO-1 and P-cadherin was comparable to that of control kidneys. Although early junctional complexes proved structurally normal, junctions with ladder-like structures and slit diaphragms were completely missing. The results indicate that nephrin is dispensable for early development of podocyte junctional complexes. However, nephrin appears to be essential for formation of junctions with ladder-like structures and slit diaphragms.

Extraintestinal CDIs occur mainly in hospitalized patients with significant comorbidities. Extraintestinal CDIs in the abdominal area may result from either intestinal perforation after infection or after intestinal surgery. Wound infections may result from colonization by feces. Clostridium difficile may reach distant sites via bacteremia. Mortality in extraintestinal CDIs is associated with the severity of underlying diseases.

CPE strains are increasingly found in Finland, but still at a very low prevalence.