The nail-patella syndrome-pathogenesis of the kidney lesion.

The nail-patella syndrome is an inheritable disorder of connective tissue in which multiple osseous abnormalities are frequently associated with renal dysfunction and proteinuria. This paper describes a unique abnormality of glomerular basement membranes (GBM) in eight patients. The abnormality consists of fibrils and bundles of cross-striated collagen within the GBM of each patient, including children with minimal proteinuria. This ultrastructural lesion may provide increased understanding of the pathogenesis of the basic defect underlying both the osseous and renal lesion.