The purpose of screening is early diagnosis and treatment. Screening tests are usually administered to people without current symptoms, but who may be at high risk for certain diseases or conditions.
to see if your kidneys are working properly. If they are not filtering the blood properly, the blood will contain excess amounts of creatinine and urea. Creatinine is a byproduct of muscle function. Urea is a waste product of protein metabolism.
to see if the kidneys are working properly. If they are not working properly, urine will contain protein. You may be asked to collect urine in a special container over a 24-hour period. This test will also show if your kidneys are clearing creatinine at a normal rate. The amount of urine produced during this test is also important. If your kidneys are failing, your urine output may be low or even completely absent.
If you have diabetes your doctor will likely check your urine every year for small amounts of protein.
The glomerular filtration rate (GFR) is a measurement of how well the kidneys are processing wastes. Your doctor can calculate the GFR based on your:
- Body size
- Blood creatinine level
The usual formula your doctor uses to estimate GFR is called the Cockcroft-Gault equation:
Creatinine clearance or GFR (mL per minute) = (140 – age) × body weight in kilogram ÷ 72 × serum creatinine. If calculated for a female, this product is multiplied by 0.85.
The GFR determines the stage of chronic renal disease.
|Stage||Glomerular Filtration Rate (GFR)|
|1||over 90 mL/min (normal)|
|2||60-89 mL/min (mild decrease)|
|3||30-59 mL/min (moderate decrease)|
|4||15-29 mL/min (severe decrease)|
|5||under 15 mL/min (kidney failure or end-stage renal disease)|
The National Kidney Foundation provides screening for people with
high blood pressure
, or a close relative with one of these conditions or with chronic renal failure.
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