Urine 24-Hour Volume Test for Creatinine

       Creatinine is a chemical waste product produced by muscle metabolism. When your kidneys are functioning normally, they filter creatinine and other waste products out of your blood. These waste products are removed from your body through urination.

A creatinine urine test measures the amount of creatinine in your urine. The test can help your doctor evaluate how well your kidneys are functioning. This is useful for diagnosing or ruling out kidney disease and other conditions affecting the kidneys.

Usually a urine 24-hour volume test will be suggested in most cases rather than one random urine test for creatinine. Although one sample of urine can be tested for creatinine, it’s more accurate to collect the urine for a whole day to get that value. The creatinine in your urine can vary a lot based on diet, exercise, and hydration levels, so a spot check is not as helpful. As the name suggests, this creatinine urine test measures the amount of urine produced in a day. It isn’t a painful test, and there aren’t any risks associated with it.

How is the 24-hour volume test performed?

To perform the 24-hour volume test, you’ll use a special container to collect your urine for the next 24 hours. Failure to follow instructions could lead to false results, which means you may have to repeat the test.

The test should begin at a specific time and end at the same time on the following day.

• On the first day, don’t collect the urine from your first time urinating. However, make sure you note and record the time. This will be the start time of the 24-hour volume test.
• Collect all your urine for the next 24 hours. Keep the storage container refrigerated throughout the process.
• On the second day, try to urinate around the same time that the test started on the first day.
• When the 24-hour period is over, cap the container and promptly return it to the lab or doctor’s office as instructed.
• Be sure to tell your doctor if you were unable to follow all the instructions. You should report any missed urine, spilled urine, or urine collected after the 24-hour time period ended. You should also tell them if you were unable to store the container of urine in a cool place.

Interpreting the results of a creatinine urine test

There are natural variations in creatinine output due to age and body mass. The more muscular you are, the higher your range will be. It’s also important to note that not all laboratories use the same values. Results are dependent on the proper collection of your urine sample.

Normal urine creatinine values generally range from 955 to 2,936 milligrams (mg) per 24 hours for males, and 601 to 1,689 mg per 24 hours for females, according to the Mayo Clinic. Creatinine values that fall outside the normal range may be an indication of:

• kidney disease
• kidney infection
• kidney failure
• urinary tract obstruction, such as kidney stones
• late-stage muscular dystrophy
• myasthenia gravis

Abnormal values can also occur in people who have diabetes or a diet that’s high in meat or other proteins.