What does urea nitrogen mean?

The human body contains a lot of chemical elements, which are necessary substances for the human body to carry out various metabolisms. A certain amount of chemical elements must be present in the body, otherwise it will affect health. For example, urea nitrogen is a very common substance that has a great effect on the kidneys. Once liver and kidney functional problems occur, it may lead to urea nitrogen imbalance. Let’s take a look at what urea nitrogen means?

It refers to "blood urea nitrogen", a nitrogen-containing compound in plasma other than protein, which is filtered through the glomerulus and excreted from the body. In cases of renal insufficiency and decompensation, BUN will increase. Therefore, it is used clinically as an indicator to judge glomerular filtration function.

Urea nitrogen is the main end product of protein metabolism in the human body. Amino acid deamination produces NH3 and CO2, both of which are synthesized into urea in the liver, with 0.3g of urea produced per gram of protein metabolism. The nitrogen content in urea is 28/60, almost half. Usually the kidneys are the main organ for excreting urea. After being filtered through the glomerulus, urea can be reabsorbed in each segment of the tubule. However, the faster the urine flow rate in the renal tubule, the less reabsorption occurs, which means that the maximum clearance rate has been reached. Like blood creatinine, blood urea nitrogen may be within the normal range in the early stages of renal impairment. When the glomerular filtration rate drops below 50% of normal, the blood urea nitrogen concentration increases rapidly. Under normal circumstances, the ratio of blood urea nitrogen to creatinine (BUN/Scr) is about 10.1. A high-protein diet, high catabolic state, dehydration, renal ischemia, insufficient blood volume and certain acute glomerulonephritis can increase the ratio, even up to 20-30. A low-protein diet and liver disease often lower the ratio, which is called hypoazotemia.

Low cause

1. Renal dysfunction. Low urea nitrogen may be related to eating too little protein, pregnancy, or liver failure.

2. Liver failure. The liver is an important metabolic organ in the human body. Liver failure can cause nutrients to not be absorbed normally. Another reason is that the patient does not take in enough protein, coupled with excessive consumption due to abnormal liver function.

There are many reasons for low urea nitrogen. Therefore, if a patient has low urea nitrogen, he or she must go to a regular hospital for examination. He or she should not simply interpret the low urea nitrogen as renal dysfunction, which would cause excessive panic. Therefore, in order to prevent unnecessary shock, it is best to do a liver function test first, confirm the cause of the disease, and then prescribe the right medicine to avoid blind treatment, which will delay treatment time.