Diabetic Renal Disease

Diabetes is a multidisciplinary disease, as many systems may need medical care. Optimal control of blood glucose level is essential to prevent diabetic complications like neuropathy, diabetic renal disease (diabetic nephropathy) and diabetic disease of eyes (diabetic retinopathy). There may also vascular and cardiac complications associated with diabetes in some patients. Diabetes may be insulin dependent (type-I) or non-insulin dependent diabetes mellitus (NIDDM or type-II diabetes). Diabetic patients develop progressive thickening of glomerular basement membrane (GBM) of glomerular capillaries along with widening of mesangium in majority of glomeruli of their kidneys. The unusual thickening of GBM and widening of mesangial area of the bundles of glomerular capillaries lead to narrowing down of functional lumen of these capillaries, there by causing pathophysiological change in the glomerular function affecting the glomerular filtration rate (GFR). Ultrastructural features of glomerulus affected by diabetes have been illustrated in Figure-1b below in comparison to normal features depicted in Figure-1a at the same magnification.

Figure-1a: Electron micrograph of a portion of the tuft of a normal glomerulus depicting normal GBM: glomerular basement membrane, Mes: mesangial area, EpC: epithelial cells or podocytes, CL: capillary lumen and US: urinary space.

Figure-1b: Electron micrograph of a portion of the tuft of a glomerulus affected by diabetes, depicting thickened GBM: glomerular basement membrane, Mes: mesangial area (widened), EpC: epithelial cell or podocyte, CL: capillary lumen (narrowed down) and US: urinary space. Note: Just compare the feature with the electron micrograph shown in figure-1a.

Uncontrolled diabetes may lead to global sclerosis of glomeruli resulting in 'end stage renal disease' (ESRD) or renal failure. Retinopathy, neuropathy and vascular and/or cardiac disease accompanying ESRD may complicate the management of prospective patients. So, diabetic patients are advised to comply sincerely with the advice of general physician or diabetologist to avoid diabetes associated complications, otherwise they may require the consultation of a nephrologist, ophthalmologist and cardiologist to manage the complications. The treatment of diabetes associated renal disease should ideally be introduced when 'traces of albumin in urine' (microalbuminuria) and polyuria (increased urine output) are detected in diabetic patients. Optimal control of diabetes by insulin and/or diet and exercise is must to avoid complications. Once massive proteinuria (excretion of >3.5 g protein per 24 hours) is developed in diabetic patients, the cost of reversal of complications may be many times higher. Just be health conscious and stay healthy & live-long.