Urea

Urea (ure) is the end product of mammalian protein catabolism. It is synthesized in the liver by ornithine and is mainly excreted by the kidneys. Because urea has a small molecular weight and is easy to dissolve, and the diffusion force is extremely large, the concentrations of urea in cerebrospinal fluid, serosal effusion, saliva, and sweat are basically the same. Blood urea concentration is mainly affected by renal function and protein intake and catabolism. At present, the most commonly used methods for determining urea in clinical laboratory are diacetyl-hydrazine method, enzyme-coupled ultraviolet spectrophotometry and o-phthalaldehyde method. Basic Information Specialist classification: urinary examination classification: urine / kidney function test Applicable gender: whether men and women apply fasting: not fasting Analysis results: Below normal: Less common in clinical practice. Mainly due to damage to the liver parenchyma, reduced production. Such as acute yellow liver atrophy, cirrhosis, toxic hepatitis, severe anemia. Normal value: Urea: 2.0-7.1mmol/L Above normal: 1 Kidney diseases such as acute renal failure, chronic nephritis, renal arteriosclerosis, chronic pyelonephritis, renal tuberculosis, advanced renal tumors, etc., when renal function is slightly impaired, BUN may be unchanged. BUN increased when 60% to 70% of the effective nephron was damaged. Therefore, BUN measurement can not be used as an indicator of early impaired renal function, but it has special value for the diagnosis of renal failure, especially uremia, and can judge the condition and estimate the prognosis. The degree of renal failure can be judged based on the BUN measurement results. A. Renal failure compensated Ccr decreased, blood Cr was normal, BUN was normal or slightly elevated (9mmol / L). C. Ccr 445 μmol/L in uremic phase, BUN>20 mmol/L. 2 pre-renal or post-renal factors cause significant reduction in urine output or urinary closure, such as severe vomiting, diarrhea caused by dehydration, edema, ascites, circulatory failure, and urinary tract stones, prostatic hypertrophy, tumors and other urinary tract obstruction . 3 excessive protein decomposition in the body, such as large area burns, major surgery, upper gastrointestinal bleeding, hyperthyroidism and acute infectious diseases. At this time, BUN increased, while other renal function tests were generally normal. negative: Positive: Tips: Do not exercise vigorously, maintain a good diet and work. The middle part of the urine is taken for inspection. Women in the menstrual period are not suitable for this examination. Normal value 2.0 to 7.1 mmol/L. Clinical significance Abnormal result 1. Increase: (1) Kidney diseases such as acute renal failure, chronic nephritis, renal arteriosclerosis, chronic pyelonephritis, renal tuberculosis, advanced renal tumors, etc., when renal function is slightly impaired, BUN may be unchanged. BUN increased when 60% to 70% of the effective nephron was damaged. Therefore, BUN measurement can not be used as an indicator of early impaired renal function, but it has special value for the diagnosis of renal failure, especially uremia, and can judge the condition and estimate the prognosis. The degree of renal failure can be judged based on the BUN measurement results. A. Renal failure compensated Ccr decreased, blood Cr was normal, BUN was normal or slightly elevated (<9mmol/L). B. Decompensation of renal failure (nitrogenemia or uremia) Ccr decreased significantly (<0.83ml/s), blood Cr increased (>90mmol/L), BUN moderately increased >9mmol/L ). C. Ccr<0.33ml/s in uremic phase, blood Cr>445μmol/L, BUN>20mmol/L. (2) Pre-renal or post-renal factors cause significant reduction in urine output or urinary closure, such as severe vomiting, dehydration caused by diarrhea, edema, ascites, circulatory failure, and urinary calculi, prostatic hypertrophy, tumors, etc. Road obstruction. (3) Excessive protein decomposition in the body, such as large area burns, major surgery, upper gastrointestinal bleeding, hyperthyroidism and acute infectious diseases. At this time, BUN increased, while other renal function tests were generally normal. 2, lower: clinically less common. Mainly due to damage to the liver parenchyma, reduced production. Such as acute yellow liver atrophy, cirrhosis, toxic hepatitis, severe anemia. People who need to be tested have severe vomiting, diarrhea, extensive burns, and abnormal kidney function. Low results may be diseases: high results of chronic nephritis may be diseases: cirrhosis precautions Before the test: prohibiting strenuous exercise, maintaining a good diet and work schedule, plasma (clear) urea content is closely related to the protein content of the food. In high-protein diets, the amount of urea in plasma (clear) can be significantly increased, while in low-protein diets, the content is significantly reduced. At the time of examination: a part of the urine is discharged first to wash away the bacteria remaining in the urethra and the anterior urethra, and then the middle part of the urine is taken for inspection. Inspection process The urine of the subject was collected and detected by chemical methods. Not suitable for the crowd Women in the menstrual period, cold patients. Adverse reactions and risks no.