NEPHRONOPHTHISIS (MEDULLARY CYSTIC-DISEASE OF THE KIDNEY) - A STUDY USING ELECTRON-MICROSCOPY, IMMUNOFLUORESCENCE, AND A REVIEW OF THE MORPHOLOGICAL FINDINGS

Abstract

Light microscopic, EM and immunofluorescent findings in kidney biopsies of 9 patients suffering from nephronophthisis are reported. The light microscopic picture is unspecific except for the cysts at the cortico-medullary junction which are present in 70% of cases. The immunofluorescent findings are either negative or unspecifically positive. On EM, the tubular basement membranes exhibit characteristic but not specific changes, i.e., homogeneous thickening, splitting, reticulation, thinning, complete loss, granular disintegration and collapse. Apparently, the structural weakness of the nephron, especially of the tubular basement membrane, may be the primary lesion in nephronophthisis.