Ultrastructure in glomerulonephritis associated with cryoglobulinemia. A report of six cases and review of the literature.

Renal tissue from 6 patients with glomerulonephritis associated with cryoglobulinemia was studied by light microscopy, immunofluorescence microscopy, and electron microscopy. Fibrillar deposits in glomerular capillaries were observed in electron micrographs in 4 of 6 patients. The ultrastructure of these deposits is compared with those in 6 previously reported cases, with the ultrastructure of the serum cryoprecipitates, and with fibrillar glomerular deposits in other glomerulonephritides. It is concluded that serum cryoprecipitates are structurally similar to glomerular deposits and that these fibrillar deposits are a frequent and possibly distinguishing morphologic feature of glomerulonephritis associated with cryoglobulinemia.