Urinalysis

Definition

Urinalysis is the physical, chemical, and microscopic examination of urine. It involves a number of tests to detect and measure various compounds that pass through the urine.

Alternative Names

Urine appearance and color; Routine urine test

How the test is performed

A urine sample is needed. Your health care provider will tell you what type of urine sample is needed. For information on how to collect a urine sample, see:

There are three basic steps to a complete urinalysis:

Physical color and appearance: What does the urine look like to the naked eye? For example, is it clear or cloudy? Pale or dark yellow or another color? The urine specific gravity test reveals concentrated or dilute the urine is.

Microscopic appearance: The urine sample is examined under a microscope. This is done to look at cells, urine crystals, mucous, and other substances, and to identify any bacteria or other microorganisms that might be present.

Chemical appearance: A special stick ("dipstick") tests for various substances in the urine. The stick contains little pads of chemicals that change color when they come in contact with the substances of interest. See also: Urine chemistry

How to prepare for the test

Certain medicines change the color of urine, but this is not a sign of disease. Your doctor may tell you to stop taking any medicines that can affect test results.

Medicines that can change your urine color include:

Chloroquine
Iron supplements
Levodopa
Nitrofurantoin
Phenazopyridine
Phenothiazines
Phenytoin
Riboflavin
Triamterene

How the test will feel

The test involves only normal urination, and there is no discomfort.

Why the test is performed

A urinalysis may be done as a part of a routine medical exam to screen for early signs of disease. This test may be done to check for blood in the urine or to diagnose a urinary tract infection. Your doctor may order this test if you have signs of diabetes or kidney disease, or to monitor you if you are receiving treatment for such conditions.

Additional conditions under which the test may be performed:

Normal Values

Normal urine may vary in color from almost colorless to dark yellow. Some foods (like beets and blackberries) may turn the urine a red color.

Usually, glucose, ketones, protein, bilirubin, are not detectable in urine. Hemoglobin, red blood cells, white blood cells, and nitrites, are not normally found in the urine.

What abnormal results mean

For specific results, see the individual test article:

What the risks are

There are no risks.

Special considerations

If a home test is used, the person reading the results must be able to distinguish between different colors, since the results are interpreted using a color chart.

Review Date: 2007-05-29
Reviewed By: Benjamin W. Van Voorhees, MD, MPH, Assistant Professor of Medicine,Pediatrics and Psychiatry, The University of Chicago, Chicago, IL. Reviewprovided by VeriMed Healthcare Network.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

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