Patients with diabetic nephropathy who experience facial swelling should not use this symptom as a basis for judging the severity of their condition. Diabetic nephropathy is divided into five stages. The condition is relatively mild during the first three stages. By the fourth stage, patients begin to exhibit significant proteinuria, and by the fifth stage, they experience severe renal failure. Conditions in these last two stages are quite severe. However, patients might also experience facial swelling during the first three stages, and while the likelihood of facial swelling increases during the fourth and fifth stages, some patients in these stages might not show obvious edema. Therefore, it is difficult to determine the severity of the condition based solely on swelling. Patients need to undergo 24-hour urinary protein quantification and blood tests to assess kidney function in order to judge the severity of their condition.