Nodular glomerulosclerosis mimicking diabetic nephropathy without overt diabetes mellitus

The duration of diabetes mellitus and presence of hyperglycemia appear to be important in the development of diabetic nephropathy. Here, we present three patients with edema, heavy proteinuria, chronic renal failure, in whom no past or present symptomatic glucose intolerance or diabetic retinopathy were found. The kidney biopsy of these patients showed diffuse glomerular basement membrane thickening and nodular glomerulosclerosis, which resembled diabetic nephropathy. The renal function of these patients deteriorated rapidly and renal replacement therapy started later in the average of 11 months since the first visiting. These cases were diagnosed as diabetic nodular glomerulosclerosis, although there was no obvious evidence for diabetes. The absence of overt diabetes and diabetic retinopathy at presentation of nodular glomerulosclerosis in these cases does not refute the hypothesis that metabolic consequence of hyperglycemia is a prerequisite for the pathogenesis of diabetic microangiopathy, but some factors other than hyperglycemia may be responsible for renal damage in our patients. The modifiable risk factors in such a condition are postulated and discussed.