The purpose of screening is early diagnosis and treatment. Screening tests are usually given to people without current symptoms, but who may be at high risk for certain diseases or conditions. Individuals with the following conditions are at high risk:
- Over 60 years
- Strong family history of chronic kidney disease
- Urinary obstruction
- Medical diseases affecting the kidneys
Early diagnosis and treatment of chronic kidney disease can prevent or delay complications. Since significant kidney disease is usually associated with a decrease in GFR and/or leakage of protein in the urine, the National Kidney Foundation recommends the following screening tests for people at increased risk for chronic kidney disease:
Creatinine is a waste product that the kidneys usually remove from the blood. When the kidneys are damaged, the creatinine level rises. A simple blood test can measure the creatinine level, which is also used to calculate the glomerular filtration rate.
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 GFR determines the stage of chronic renal disease.
Urine Protein Level
During the filtering process, the kidneys usually return protein to the circulation. With chronic kidney disease, the kidneys allow protein to leak into the urine. Different kinds of proteins can leak into the urine. Albumin is a protein that often appears in the urine of people who have chronic kidney disease caused by high blood pressure or diabetes.
The guidelines of the National Kidney Foundation recommend two tests to check the urine protein level:
- Protein-to-creatinine ratio
- Albumin-to-creatinine ratio
To perform these tests, the laboratory compares the amount the protein or albumin to the amount of creatinine in a urine sample.
Depending on your risk factors, your doctor may also order the following screening tests:
Electrolytes, such as sodium and potassium, are minerals needed for the body to work well. Chronic kidney disease causes changes in the electrolytes. A simple blood test can measure the levels of these substances.
Chronic kidney disease causes changes in the ability to adjust the concentration of the urine. A simple test can measure the urine concentration.
Chronic kidney disease causes changes in the pH, or acid level, of the urine. A simple test can measure the urine pH.
- Reviewer: Adrienne Carmack, MD; Michael Woods, MD
- Review Date: 07/2013 -
- Update Date: 05/11/2013 -