See my highlighted links at the bottom for links to instructions for this test in Spanish and other foreign languages.
What's the Purpose of Urine Testing?
An incredible amount of information can be obtained from examining a urine sample. In fact, over 100 different tests can be performed on a single specimen. Most of the time a simple "quick catch" specimen of urine (voided into a cup) is sufficient for a basic urine test. Urinalysis results may reveal problems with the body's electrolytes or hormones, the presence of infection, dehydration, evidence of microscopic blood (that can't be seen with the naked eye), drug levels, or problems with kidney function.
Why a 24-Hour Urine Collection?
A small sample of urine isn't always sufficient. In addition to blood tests, physicians will order a 24-hour urine collection if they have reason to be concerned about overall kidney function. This test typically focuses on creatinine clearance, sodium, protein, and urine osmolality. Other substances may be examined in a 24-hour collection; for example, hormone levels, urea nitrogen, or copper. The volume of urine that is voided during the 24-hour period also yields important information. The laboratory will make calculations based on your 24-hour (or 12-hour) urine collection that will help determine how well your body is clearing waste products via the urine. This finding will be compared to a blood test that measures how much of the waste products are circulating in your blood.
If your physician hasn't explained WHY he or she is requesting the 24-hour urine collection, ask for details. As a patient, being informed is one of your fundamental rights.
Tips for Collecting Your 24-Hour Urine Specimen
A 24-hour urine collection is easy to mess up, and that can be very frustrating. Just one moment of accidentally forgetting to collect and save the urine during the 24-hours ruins the test, and the collection might have to start all over again . . .
Before the test: Your doctor's office will provide you with one or two brown plastic collection jugs and written instructions. Certain tests may require that urine be placed in a "double container" or that a preservative be added to the collected urine; you'll be given the supplies and containers appropriate for your test.
What you need from your lab or doctor's office:
- Special instructions for the test and a lab sticker with your patient information to attach to the collection container(s).
- Collection container(s)--depending on the size of container the lab stocks--you may receive one or two of these jugs. They are made of heavy brown plastic, not just any container will do for this collection, so be sure to use the container(s) provided.
- Nice to have items--I'd ask for these if they don't offer them to you. For men: A plastic urinal to void into. For women: a plastic "nun's hat" to set in the toilet to collect the voided urine. If you don't have these items, it's okay to void into a bedpan, large plastic cup or bowl, etc. You will pour the collected urine into the brown collection container after each void, so it's nice to have something that pours easily.
- You'll also need: a way to keep the collected urine cool during the collection period. One of the most common ways to do this is to set the brown urine collection jug in larger container filled with icy water (an ice bath). An ice chest (cooler) is another option. It's also possible to place the collection jug in the refrigerator, although there are many reasons to make this impractical.
Ready to start? Completely empty your bladder by voiding into the toilet and flushing--DO NOT save this first urine sample. The first time you empty your bladder you are flushing away urine that has been building up in your bladder for several hours or more. That hours-old urine will yield incorrect results if we collect it for our 24-hour specimen. We want to start with an empty bladder to collect only the urine our body makes during the 24-hour-period.
Record the start time and determine your stop time. All other urine during the 24-hours will need to be saved and poured into the collection jug. It's helpful to use the same bathroom all day long and post a note with the start/stop time to help remind you to collect all of your samples. Replenish the ice in the basin surrounding your collection jug from time-to-time in order to keep the specimen cool.
Ending the collection: When the 24-hour-collection period is ending, make a last effort to urinate--even if you don't have the urge to "go," you will still be able to produce an ounce or two of urine. Make sure your collecton jugs are tightly capped and labelled with your name, date of birth, collection date and start/stop times. (Note: If you weren't given a label for your specimen jug, make one and tape it securely to your jug.) Keep the specimen in the ice bath, cooler, or refrigerator until you are ready to return it to the lab or doctor's office. Place your specimen jug(s) in a sturdy plastic bag for easy carrying. (Your specimen will be just fine without being on ice while you return it to the lab or doctor's office---as long as you are not exposing it to heat for a prolonged period of time.)
What If . . . ? Special circumstances . . .
- You filled up the container the lab provided, but your 24-hour-collection is not yet complete. Use a very clean glass or plastic container to continue collecting your urine. Your brown jug protects the collected urine from light--so if you have to use a transparent collection bottle, be sure to guard it from the light along with keeping it chilled. Using an ice chest would be a good strategy for you in this case--if that's not possible, cover the transparent container with a brown paper bag to protect it from the light. When you return your sample to the lab, keep the transparent container in a brown paper bag, or some similar technique to keep it protected from the light.
- You have started the 24-hour-collection, but find you need to leave the house for several hours. Take a backpack with you, a plastic bottle with a secure lid, and a large ziplock bag full of ice. This will allow you to carry your collection items discreetly. For ladies, a wide mouthed plastic container will allow you to urinate and pour the sample into your capped bottle. Your ziplock bag of ice will help keep your sample cool while you are on the go. I know this is a rather bulky idea, but the best I can come up with at the moment.
- For patients with urinary catheters. It would be preferable to start your collection with a fresh catheter bag in place--if that's not possible, it would be nice to clean the existing bag--at least remove the bag from the catheter and give it a good rinse out.. Begin your collection by completely emptying the current catheter bag and flushing the accumulated urine. Record this as your start time. During the remainder of the 24-hour-collection period, empty the foley bag into the brown collection jugs at regular intervals and keep the collection jugs in the refrigerator on in an ice bath just as anyone else would do. At the designated stop time, empty your collection bag for the last time.
- Urine becomes mixed with feces or blood. Do not empty any urine that has been contaminated by feces or menstrual blood into your collection jug. Make note of the time and stop the collection. Contact your lab or physician's office to inform them. In some cases, if enough time has elapsed (12 hours or more), your physician may give the go-ahead to stop the test early. Possibly, you may be asked to start all over again.
- Patients who are incontinent (cannot hold their urine). Certainly your physician may not realize (or remember) that a particular patient struggles with complete or partial incontinence. Do let your doctor know about incontinence issues. Perhaps the 24-hour-test will be impossible because of complete incontinence; perhaps they might recommend a bladder catheter for the test, or perhaps they might allow a shorter period of time (12-hours or thereabouts) for the urine collection.
- "Oops! I didn't collect every void during the 24 hours!" If you forget to collect all of your urine, the test results may be inaccurate. Talk to your lab or doctor's office before disposing of all that you've collected. If you have already completed at least 12 hours of the urine collection, mark down the time of the last urination and keep your container on ice or in the refrigerator as discussed later in this article. Talk to your physician's office or lab to let them know what you have been able to collect. They should be able to use your sample and calculate the important information based on the number of hours you have collected--but it's important that they know the correct number of hours when you turn in the sample. It's possible that you'll be asked to start all over again, but there's a good chance that they can use what you've collected and make adjustments to correctly calculate the results.
- Why keep the urine specimen on ice? The ice bath is just a technique for keeping the urine cool enough so that bacterial growth doesn't overwhelm your specimen. The ice bath should keep your specimen in the 40-45 degree Farenheit range as would your refrigerator. Keeping a 24-hour-specimen in the refrigerator is really awkward and inconvenient. Having your specimen container right there in the bathroom "on ice" is so much easier.
- Other questions? Call your physician's office or lab. If you'd like to suggest anything to make this entry more helpful or accurate--please let me know. I'll gladly tweak this entry to make the information more user-friendly.
- Procedures and Diagnostic Tests (From the National Institute's of Health)
- Instructions for a 24-Hour Urine Collection (in English) (648 KB) (in Spanish) (32 KB) (also from NIH)
- Health Info Translations: Get instructions for this test in Spanish, Korean, Japanese, Chinese, French, Somali, Russian and Ukranian.
- St. Clare Hospital Health Service: Patient Education Brochure, 24-hour urine collection: These comprehensive instructions allow the doctor ordering the test to also provide specific dietary instructions to follow depending on what element of the urine is being tested.
- A 2008 Renal/Urology article that discusses how 12-hour-urine samples can be substituted in place of 24-hour-samples: 24-hour-urine collection may be avoidable.
- Please do try your level best to complete the 24-hour-collection for best results. If you run into a problem with your collection after 12 hours or more, ask your doctor or lab if they can calculate your results using what you have collected.