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 testHow 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:
- Clean catch urine specimen
- 24-hour urine collection
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:
- Acute bilateral obstructive uropathy
- Acute nephritic syndrome
- Acute tubular necrosis
- Acute unilateral obstructive uropathy
- Alkalosis
- Alport syndrome
- Analgesic nephropathy
- Anorexia nervosa
- Atheroembolic renal disease
- Atrial myxoma
- Bladder stones
- Chronic bilateral obstructive uropathy
- Chronic glomerulonephritis
- Chronic or recurrent urinary tract infection
- Chronic renal failure
- Chronic unilateral obstructive uropathy
- Chronic urethritis
- Complicated UTI (pyelonephritis)
- Congenital nephrotic syndrome
- Cystinuria
- Delirium
- Dementia
- Dementia due to metabolic causes
- Diabetes insipidus -- central
- Diabetic nephropathy/sclerosis
- Enuresis
- Epididymitis
- Failure to thrive
- Focal segmental glomerulosclerosis
- Goodpasture's syndrome
- Heart failure
- Hemolytic-uremic syndrome (HUS)
- Henoch-Schonlein purpura
- Insulin-dependent diabetes (IDD)
- IgA nephropathy (Berger's disease)
- Injury of the kidney and ureter
- Interstitial nephritis
- Irritable bladder
- Left-sided heart failure
- Lupus nephritis
- Malignant hypertension (arteriolar nephrosclerosis)
- Medullary cystic disease
- Membranoproliferative GN I
- Membranoproliferative GN II
- Membranous nephropathy
- Myelomeningocele (children)
- Necrotizing vasculitis
- Nephrotic syndrome
- Noninsulin-dependent diabetes (NIDD)
- Orchitis
- Ovarian cancer
- Paroxysmal nocturnal hemoglobinuria (PNH)
- Polycystic kidney disease
- Post-streptococcal GN
- Prerenal azotemia
- Primary amyloid
- Prostate cancer
- Prostatitis, acute
- Prostatitis, chronic
- Prostatitis, non-bacterial
- Pyelonephritis; acute
- Rapidly progressive (crescentic) glomerulonephritis
- Reflux nephropathy
- Renal papillary necrosis
- Renal tubular acidosis; distal
- Renal tubular acidosis; proximal
- Renal vein thrombosis
- Retrograde ejaculation
- Rhabdomyolysis
- Right-sided heart failure
- Secondary systemic amyloid
- Stress incontinence
- Systemic lupus erythematosus
- Systemic sclerosis (scleroderma)
- Thrombotic thrombocytopenic purpura
- Traumatic injury of the bladder and urethra
- Ureterocele
- Urethral stricture
- Urethritis
- Wegener's granulomatosis
- Wilms' tumor
Normal Results
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:
- Bilirubin - urine
- Glucose - urine
- Protein - urine
- Red blood cells in urine test
- Urine ketones
- Urine pH
- Urine protein
- Urine specific gravity
Risks
There are no risks.
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.
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.
