GLOMERULOPATHY ASSOCIATED WITH PREDOMINANT FIBRONECTIN DEPOSITS - A NEWLY RECOGNIZED HEREDITARY-DISEASE

A newly recognized type of familial glomerulopathy observed in patient s of both sexes in six families is reported. Proteinuria, often within the nephrotic range, microscopic hematuria, hypertension and a slowly decreasing renal function over several years were common. No underlyi ng systemic diseases were identified. Generally, light microscopy show ed enlarged glomeruli with minimal hypercellularity and with extensive deposits in the mesangium and subendothelial space. By electron micro scopy, granular deposits with some admixture of fibrils were most comm on. In one family, the deposits were predominantly fibrillary. Immunog lobulins and complement factors were inconstant or lacking. A main fin ding was a strong immune reactivity to fibronectin, corresponding to t he distribution of the deposits. In one patient, the deposits recurred in a renal transplant. There was no indication of systemic deposition . Abnormalities in the metabolism of circulating fibronectin may play a pathogenetic role in this disease of probably autosomal dominant inh eritance.