The length of time urine can be stored before testing is crucial for a urinalysis. Failure to store properly can lead to false positive and false negative results. So, how long can urine be stored before testing is performed for a urinalysis?
Overview of a Urinalysis
A urinalysis is used for several different purposes and is one of the most common medical tests performed. The test may often be ordered at routine check ups, upon hospital admission, and/or if the physician is checking for something specific. However, handling of the specimen of urine is very important. Urine that is stored too long or stored improperly before testing is not considered viable. Storage requirements for urine is usually dependent on why the test is being performed and how the specimen was obtained.
Storage procedures for urine specimens to be analyzed are of high importance. If not handled properly, contamination can often result. Some of the most common storage procedures for the specimen is to refrigerate or put the specimen on ice. This is especially so if the urinalysis can not be performed immediately. While methods will vary among the individual lab setting and what is being screened for, this is a universal practice. Urine that can not be tested within a short time frame should be preserved to reduce microbial growth that can result in contamination of the specimen.
As previously mentioned, the length of time urine can be stored before the testing is performed for a urinalysis can be dependent on many factors. Some specific tests are analyzed by utilizing what is known as a reagent strip. These strips are dipped in the urine briefly and results are read by means of an automated machine and/or color changes. Performing a urinalysis with this method may require that the specimen be tested within one hour of collecting, depending on what the physician is looking for. According to Cornell University, a urine specimen can be held for up to twelve hours, providing that it has been refrigerated. In addition to time restraints, temperature of the urine can also play a critical role in the end test result. Refrigerated specimens must be allowed to become room temperature before testing.
The urinalysis is used as a diagnostic tool in many regards. Collection methods, times, and other pertinent information are fairly stable but will vary by the facility. In some instances, the patient may even be able to collect his or her own urine at home and take to the lab or physicians office. In this case, urine should be immediately taken to the particular facility. Those that are unsure should ask their physician how long the urine can be stored before the testing is performed for the urinalysis.