24-hour urine creatinine clearance calculator, formula (GFR-test procedure)

A 24-hour urine creatinine clearance calculator uses to calculate the creatinine filtration.

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24-hour urine creatinine clearance formula

GFRt or C.Clearance = U * V / P * 24 * 60

• U: Creatinine concentration in Urin
• V: Rate of urine formation
• P: Creatinine amount in plasma

What is the Glomerular Filtration Rate test mean?

The glomerular Filtration Rate test or GFRt is a short form of the glomerular filtration rate test. It is a specific test to check renal function. GFRt range tends to decrease with the increase of renal damage. GFR becomes zero at renal failure.

Glomerular filtration rate test (GFR test) or eGFR is an important test for checking the filtration percentage of kidneys. Each kidney consists of 1 million nephrons (The functional unit of the kidney).

Glomerular filtration occurs at the glomerular capillaries, which surround the nephrons. Filtration of substances occurs due to high osmotic pressure at the capillaries site the substance is filtered by the bowman capsule at the range of 125 ml/minutes.

Due to small pores, cells and large proteins are unable to pass through the semipermeable membrane of the Bowman capsule.

Principle of glomerular filtration rate test

A creatinine clearance test is used to check the glomerular filtration rate of kidneys. Therefore this test is also called as glomerular filtration rate test (GFRt).

“The amount of plasma creatinine cleared by the glomeruli in unit time is called glomerular filtration rate (GFR).

The procedure of Glomerular filtration rate test estimation

The following steps are performed while estimating the glomerular filtration rate.

1. Asked the patient to collect the 24 hours urine in a clean bottle.
   1. Note: The first specimen should be discarded. Urine volume is measured in meli litter.
2. A blood sample (Measuring the s.creatinine) can be collected at any time during these 24 hours.
3. Measure the creatinine on both serum and 24 h collected urine.

NOTE: Creatinine in the urine is high and calculated as mmol/l but creatinine concentration in serum is small and measured in micromol/litter. Therefore before calculation, the urine creatinine unit converts into micromol /litter by multiplying 1000, instead of mmol/l.

What is the indication of the glomerular filtration rate test (Creatinine clearance)?

Following are the indications of creatinine clearance.

1. GFRt or creatinine clearance is helpful in the assessment of potential kidney donors.
2. It helps in the diagnosis of abnormal renal function patients.
3. Creatinine clearance is helpful is assessing the effects of toxic drugs on kidneys.

Creatinine clearance normal range chart in male and female

Male	75-140 ml/min
Female	60-120 ml/min