[Congenital nephrotic syndrome]

Only one case of congenital nephrotic syndrome was recorded in a series of 2,500 bioptic examinations of the kidney performed over a period of 20 years. In necroptic material examined over the same period of time congenital nephrotic syndrome was recorded three times. At the first bioptic examination of the kidneys only minimal changes of glomeruli were diagnosed. Rebiopsy exhibited proliferation of mesangial cells, focal segmental glomerular sclerosis, cystically dilated tubules in the juxtamedular region of the cortex, and focal tubulointerstitial reactive changes, which in accordance with the clinical findings were assessed as congenital nephrotic syndrome of the Finnish type. Comparison of the findings observed at the first biopsy and at rebiopsy demonstrates the importance of proper collection of a representative sample for renal biopsy.