Impaired glucose metabolism - A potential risk factor for idiopathic nodular glomerulosclerosis: A single center study

Nodular glomerulosclerosis is a characteristic histological finding of diabetic nephropathy (DN) with thickened glomerular basement membrane and hyalinized arterioles. Idiopathic nodular glomerulosclerosis (ING), a distinct clinicopathologic entity, is the term used to denote classic DN confirmed by light microscopy, immunofluorescence, and electron microscopy but in the absence of diabetes mellitus (DM). ING has been linked to heavy tobacco smoking, chronic hypertension, and obesity. We report the result of a retrospective study identifying seventeen subjects from Thomas Jefferson University (1999-2014) with biopsy-proven nodular glomerulosclerosis but no pre-existing history of DM. The main indications for percutaneous kidney biopsy (PKB) were either reduced renal function or the presence of proteinuria. The subjects' mean (+/- SD) age was 60.2 (14.4) years, their highest documented random glucose level was 104.4 (23.5) mg/dL, serum creatinine measured 2.35 (1.03) mg/dL, and body mass index calculated 29.4 (6.2) kg/m(2). None of the patients fulfilled criteria for diabetes at the time of PKB. However, review of medical records revealed history of intermittently elevated blood glucose or borderline-high HgbAlc levels. The role of impaired glucose metabolism or insulin resistance, as a possible etiology for ING is potentially underestimated and needs additional studies.