Idiopathic nodular glomerulosclerosis is an unusual entity with light micro
scopic and ultrastructural features similar to those of nodular diabetic gl
omerulosclerosis but without evidence of abnormal glucose metabolism. We re
port 2 patients whose renal biopsies showed nodular glomerulosclerosis with
afferent and efferent arteriolosclerosis, glomerular basement membrane thi
ckening, focal mesangiolysis and capillary microaneurysm formation, and who
had no evidence of abnormal glucose metabolism or other features of diabet
es mellitus. Review of the literature shows that, of the 27 reported cases
of idiopathic nodular glomerulosclerosis (not including the 2 cases reporte
d herein), 11 showed evidence of abnormal glucose metabolism or were frankl
y diabetic. Of the remaining 16 cases with normal serum blood glucose measu
rements, 3 had diabetic retinopathy and 1 had a delayed insulin response cu
rve. The cause and pathogenesis of the glomerular nodules are discussed, an
d it is suggested that arteriolar stenosis and glomerular ischemia may be i
nvolved in the development these lesions. (C) 1999 by the National Kidney F
oundation, Inc.