A case of idiopathic nodular glomerulosclerosis mimicking diabetic glomerulosclerosis (Kimmelstiel-Wilson type).

A case of idiopathic nodular glomerulosclerosis mimicking diabetic Kimmelstiel-Wilson glomerulopathy is reported. The patient was a 45-year-old man suffering from nephrotic syndrome. Light and electron microscopy revealed diffuse and nodular glomerulosclerosis indistinguishable from diabetic nodular glomerulosclerosis. Diabetes mellitus, however, had been excluded both by extensive clinical and by laboratory investigation. The differential diagnosis also included amyloidotic and non-amyloidotic fibrillary glomerulopathy, light chain glomerulopathy, collagen type III disease, immunotactoid glomerulopathy, and the sclerosing variant of membranoproliferative glomerulonephritis. Immunohistochemistry and ultrastructural investigations, however, excluded these entities, and the diagnosis of idiopathic nodular glomerulosclerosis was made. This variant has to be included in the differential diagnosis of nodular glomerulopathy associated with nephrotic syndrome.