Stage three of diabetic nephropathy refers to patients who have persistent microalbuminuria, indicating a relatively mild state of the disease at this time. In fact, diabetic nephropathy is divided into five stages. During the first and second stages, patients generally do not exhibit specific symptoms clinically and may even test negative for proteinuria; however, an increase in kidney size and glomerular filtration rate may occur. By the third stage, patients begin to exhibit small or micro amounts of urinary albumin. The pathological damage to the kidneys at this stage is not considered particularly severe. Patients may experience hyalinization of small arteries and nodular lesions in the glomeruli. Within the staging of diabetic nephropathy, this does not constitute a particularly severe phase; however, the condition of the patients may continue to progress, leading to significant proteinuria and even renal failure.