Serum creatinine clearance; Kidney function - creatinine clearance; Renal function - creatinine clearance DefinitionThe creatinine clearance test helps provide information about how well the kidneys are working. The test compares the creatinine level in urine with the creatinine level in blood. How the Test is PerformedThis test requires both a urine sample and blood sample. You will collect your urine for 24 hours and then have blood taken. Follow instructions exactly. This ensures accurate results. How to Prepare for the TestBefore the test, your health care provider may ask you to stop taking medicines that may affect the test results. These include some antibiotics and stomach acid medicines. Be sure to tell your provider about all the medicines you take. Do not stop taking any medicine before talking to your provider. How the Test will FeelThe urine test involves only normal urination. There is no discomfort. When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away. Why the Test is PerformedCreatinine is a waste product of creatine. Creatine is a chemical the body makes to supply energy, mainly to muscles. The creatinine clearance test compares the creatinine level in urine with the creatinine level in blood. This gives an estimate of the glomerular filtration rate (GFR). GFR is a measure of how well the kidneys are working, mainly the kidneys' filtering units. These filtering units are called glomeruli. Creatinine is removed, or cleared, from the body by the kidneys. If kidney function is abnormal, creatinine level increases in the blood because less creatinine is excreted through the urine. Normal ResultsClearance is often measured as milliliters per minute (mL/min) or milliliters per second (mL/s). Normal values are:
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider to know about the meaning of your specific test results. What Abnormal Results MeanA lower than normal creatinine clearance may indicate:
RisksThere is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others. Other risks associated with having blood drawn are slight, but may include:
ReferencesGharavi AG, Landry DW. Approach to the patient with renal disease. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 100. Oh MS, Briefel G, Pincus MR. Evaluation of renal function, water, electrolytes, and acid-base balance. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 15. | |
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Review Date: 8/20/2023 Reviewed By: Jacob Berman, MD, MPH, Clinical Assistant Professor of Medicine, Division of General Internal Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. Editorial update: 02/07/2024. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. No warranty of any kind, either expressed or implied, is made as to the accuracy, reliability, timeliness, or correctness of any translations made by a third-party service of the information provided herein into any other language. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited. | |
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Creatinine tests
