Renal artery dysplasia in a patient with membranoproliferative glomerulonephritis.

A 27 year old man with nephrotic syndrome due to membranoproliferative glomerulonephritis had multifocal stenoses of the renal and intestinal arteries. The arterial lesions demonstrated by angiograhy closely resembled those of medial fibromuscular dysplasia. The dysplasia progressed over a five year period to involve both renal arteries from their extrarenal segments through their interlobar branches. Low serum levels of complement components C3 and C4, focal reduplication of the glomerular basement membrane on light microscopy, and the patterns of glomerular localization of IgG and C3 by immunofluorescence were characteristic of type I membranoproliferative glomerulonephritis. The development of the arterial dysplasia in a patient with chronic glomerulonephritis suggests a common immunologic pathogenesis of both disorders.