"Diabetic nephropathy" in a non-diabetic patient

Kimmelstiel and Wilson originally described nodular glomerulosclerosis as the pathognomonic lesion of diabetic nephropathy. Nevertheless, nodular glomerulosclerosis pattern can rarely occur in non-diabetic patients. In such cases, the differential diagnosis includes membranoproliferative glomerulonephritis, light or heavy chain deposition disease, amyloidosis, fibrillary and immunotactoid glomerulonephritis and chronic hypoxic or ischemic conditions. In cases that the above entities cannot be proven, the term idiopathic nodular glomerulosclerosis is given. Here, we report a case of a male patient with renal failure stage IV and non-nephrotic range proteinuria. He had a history of heavy smoking and hypertension. The kidney biopsy revealed diabetic-like lesions. However, there was no evidence of glucose impairment despite the thorough work-up at the biopsy time and thereafter. The laboratory data and the electron microscopy of the specimen could not prove any other cause of nodular glomerulosclerosis, and the final diagnosis was idiopathic nodular glomerulosclerosis. Moreover, we focus on the pathological differential diagnosis and work-up.