Orthostatic Proteinuria Test
A child requiring this test is found to have protein in the urine, a condition known as Proteinuria. Sometimes this is a sign of serious kidney disease. Other times, however, this is a normal finding which seems to be related to body position. Protein in the urine caused by the upright position is called Postulatory or Orthostatic Proteinuria, and is not serious. The test is performed in order to establish if the protein in a child's urine is caused by the upright position.
The test can be only positive or negative. The test is positive when protein is absent from the first voided morning urine, and present in a specimen collected later in the day. A positive test for Orthostatic Proteinuria rules out nephritis or nephrosis as the cause of the urinary abnormality.
Urine samples are to be collected with a special set of containers by following these steps.
Steps to Collecting Urine
- Check to be sure that the bag received has 6 screw top urine containers. Each of these should be labeled with the child's name, hospital number and birth date. An additional label should be present, so that the date and time each urine sample was collected can be recorded.
- 2 urine samples are to be collected on 3 separate days: a first morning urine in one container, and a second urine specimen from any other time during the day.
- The test is optimally performed on days when the child will be upright and active during most of the day.
- Each time one of these urines is collected, write the date and time the urine was collected on the blank label which is already attached to the container.
- The containers should be about half-filled (3mL). They may be stored in the plastic bag in your refrigerator until all 6 are filled.
IMPORTANT NOTE: The specimen should NOT be frozen.
Collecting Morning Urine
It is particularly important that the morning urines be collected in a very specific way. On the night before obtaining this morning specimen, the child should empty his or her bladder by voiding in the toilet and immediately go to bed. Urine voided during the night should also be discarded in the toilet. The first morning urine should be collected immediately after he or she gets out of bed. The urine should not be collected after the child has been up walking around the house for a while, after breakfast, etc.
Returning Urine Samples
When all 6 urine specimens are collected, bring them in a bag to the Test Referral Center at Cincinnati Children's Main Campus, or any of the Cincinnati Children's Laboratories outpatient facilities. The Main Campus Test Referral Center hours are normal business hours (9 am - 5 pm); for outpatient facility hours and details, contact the individual outpatient facility.
Test results can be discussed with one of the Nephrology nurses a day or two after drop-off. Contact one of the Nephrology nurses for test results or questions at 513-636-4531.
