The urine 24-hour volume test measures the amount of urine produced in a day. The amounts of creatinine, protein, and other chemicals released into the urine during this period are usually tested as well.
A clean-catch urine sample is performed by collecting the sample of urine in midstream. Men or boys should wipe clean the head of the penis. Women or girls need to wash the area between the lips of the vagina with soapy water and rinse well. A small amount of urine should initially fall into the toilet bowl before it is collected (this clears the urethra of contaminants). Then, in a clean container, catch about 1 to 2 ounces of urine and remove the container from the urine stream. The container is then given to the health care provider.
How the Test is Performed
For this test, you must urinate into a special bag or container every time you use the toilet for a 24-hour period.
- On day 1, urinate into the toilet when you get up in the morning.
- Afterward, collect all urine in a special container for the next 24 hours.
- On day 2, urinate into the container when you get up in the morning.
- Cap the container. Keep it in the refrigerator or a cool place during the collection period.
- Label the container with your name, the date, the time of completion, and return it as instructed.
Certain drugs can also affect the test results. Your provider may tell you to stop taking certain medicines before the test. Never stop taking medicine without first talking to your provider.
The following may also affect test results:
- Dehydration
- Dye (contrast media) if you have a radiology scan within 3 days before the urine test
- Emotional stress
- Fluid from the vagina that gets into the urine
- Strenuous exercise
- Urinary tract infection
How the Test will Feel
The test involves only normal urination and there is no discomfort.
Why the Test is Performed
You may have this test if there are signs of damage to your kidney function on blood, urine, or imaging tests.
Urine volume is normally measured as part of a test that measures the amount of a substances passed in your urine in a day, such as:
- Creatinine
- Sodium
- Potassium
- Urea nitrogen
- Protein
- Copper
This test may also be done if you have polyuria (abnormally large volumes of urine), such as is seen in people with diabetes insipidus.
Normal Results
The normal range for 24-hour urine volume is 800 to 2,000 milliliters per day (with a normal fluid intake of about 2 liters per day).
The examples above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test results.
What Abnormal Results Mean
Disorders that cause reduced urine volume include dehydration, not enough fluid intake, or some types of chronic kidney disease.
Some of the conditions that cause increased urine volume include:
- Diabetes insipidus – renal
- Diabetes insipidus – central
- Diabetes
- High fluid intake
- Some forms of kidney disease
- Use of diuretic medicines