The danger of elevated urea nitrogen: 1, elevated urea nitrogen is the most common renal diseases, such as glomerulonephritis caused by chronic renal failure or acute renal failure, etc., will lead to elevated urea nitrogen, once the renal failure, the patient will have a decline in the ability to detoxify, water and sodium retention, and ultimately may be a series of hazards of the body’s systems, such as cardiovascular system will have heart failure, Digestive system may appear peptic ulcer and digestive bleeding, increase the risk of cardiovascular and cerebrovascular accidents, as well as serious internal environmental disorders, and ultimately even lead to uremia, life-threatening; 2, elevated urea nitrogen is also seen in a large amount of peritoneal effusion, gastrointestinal bleeding, infections and other such cases, once the above mentioned situation, the serious life-threatening and even lead to death.