Organic renal impairment, prerenal oliguria, and excessive protein catabolism or intake are most often considered causes of high urea nitrogen.
Blood urea nitrogen belongs to the end product of protein metabolism, when the renal parenchyma is damaged, the glomerular filtration rate decreases, resulting in an increase in blood urea concentration, so blood urea nitrogen can be a rough observation of glomerular filtration function. The normal range of blood urea nitrogen is 3.2~7.1mmol/L in adults and 1.8~6.5mmol/L in children.
1.Organic renal impairment: chronic renal failure caused by various reasons, such as primary glomerulonephritis, pyelonephritis, interstitial nephritis, etc. In addition, when glomerular filtration rate decreases in acute renal failure, the blood urea nitrogen can also be elevated.
2. Pre-renal oliguria: blood volume insufficiency or reduced renal blood flow caused by various reasons, such as severe dehydration, large amount of peritoneal fluid, hepatorenal syndrome, etc., blood urea nitrogen can be decreased on its own after active volume expansion treatment.
3. Protein catabolism or excessive intake: such as acute infectious diseases, extensive burns, severe trauma or after a high protein diet, but the blood creatinine is generally not elevated, after removing the cause, the blood urea nitrogen can be decreased.
High urea nitrogen may also have other reasons, when the patient has elevated urea nitrogen, it is recommended to go to the regular hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.