endogenous creatinine clearance

Endogenous creatinine is produced by the metabolism of creatinine in the body. The daily production is relatively stable. The creatinine is not absorbed by the renal tubules through the blood through the glomerular filtration, and is excreted with the urine. Under controlled conditions, urinary creatinine excretion is fairly constant. The condition that the kidneys remove all endogenous creatinine in a few milliliters of blood per unit time can be used for judging the degree of renal damage. 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: The endogenous creatinine clearance rate in most acute glomerulonephritis is as low as 80% of the normal value. Normal value: Endogenous creatinine clearance (male): 85-125ml/min Endogenous creatinine clearance (female): 75-115ml/min Above normal: In the nephropathy type, due to the increased permeability of the renal tubule basement membrane, endogenous creatinine can be excreted from the renal tubule, and the Ccr result is correspondingly high. negative: Positive: Tips: Eat a low-protein diet for 3 days, the daily protein should be less than 40g, and fasting meat (no creatinine diet) to avoid strenuous exercise. Normal value The male clearance rate was 105 ± 20 ml / min; the female was 95 ± 20 ml / min. Clearance rates decrease with age. Clinical significance Abnormal result 1. Sensitive indicators for judging glomerular filtration function: Most acute glomerulonephritis has an endogenous creatinine clearance rate as low as 80% of the normal value, but serum urea nitrogen and creatinine are still in the normal range, so it is earlier. Reflects glomerular filtration. 2, preliminary assessment of the degree of damage to renal function: mild damage Ccr in 70 ~ 51ml / min; moderate damage in 50 ~ 31ml / min; less than 3ml / min for severe damage, chronic renal failure patients if the clearance rate 20 ~ 11ml /min is early renal failure; 10 ~ 61ml / min for advanced renal failure; less than 5ml / min for end-stage renal failure. 3, guiding treatment: endogenous creatinine clearance rate of less than 30 ~ 40ml / min, should limit protein intake; less than 30ml / min thiazide diuretic treatment is often ineffective; less than 10ml / min should be combined with clinical dialysis treatment, diuretics The response (such as furosemide, sodium diureate) has been extremely poor. In addition, in renal failure, any drug that is metabolized by the kidney or excreted by the kidney can also adjust the time of administration and the time of administration according to the degree of Ccr reduction. 4, the reference of clinical classification of chronic nephritis: such as chronic nephritis common Ccr often reduced. In the nephropathy type, due to the increased permeability of the renal tubule basement membrane, endogenous creatinine can be excreted from the renal tubule, and the Ccr result is correspondingly high. Need to check the crowd Suspected patients with abnormal renal function. Low results may be diseases: chronic renal failure in the elderly, nephritis after acute infection in the elderly, acute renal failure in children, diabetic nephropathy in children, chronic renal failure in children, chronic glomerulonephritis, uremia, immune-mediated kidney Disease, elderly chronic pyelonephritis, pregnancy with acute glomerulonephritis precautions Preparation before inspection: Continuously eat low-protein diet for 3 days, daily protein should be less than 40g, and fasted meat (no creatinine diet) to avoid strenuous exercise. When checking: Pay attention to the maintenance of urine to avoid contamination. Inspection process The urine was drained at 8 am, then 24 hours of urine was collected, and 4-5 ml of toluene was added to prevent corrosion. In 4 days (anytime), take anticoagulation 2-3ml, and check with 24h urine. Urine and plasma creatinine concentrations were measured and 24 h urine volume was measured. Endogenous creatinine clearance was calculated for 24 h using the following formula: 24 h endogenous creatinine clearance = (urinary creatinine concentration (umol/L) x 24 h urine volume (L)) / (plasma creatinine concentration (umol/L)). Not suitable for the crowd no. Adverse reactions and risks no.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.