Diabetes can cause many complications and diabetic nephropathy is a common cause of diabetic foot swelling. Kidney lesions cause a large amount of protein to be excreted from the urine and the plasma osmotic pressure to decrease, causing water to collect in the body. Chronic hyperglycaemia in diabetic patients increases the viscosity of the blood and predisposes to vascular inflammation causing vascular occlusion, therefore diabetic patients can experience swollen feet.