Urinalysis

A urinalysis is the study of the physical, chemical, and microscopic properties of urine. The tests detects and evaluate several compounds in the urine, such as by-products of normal and abnormal metabolism, cells and cellular fragments, and bacteria present in the urine.

 

Urine is produced by the kidneys. The kidneys flush wastes out of the blood, help regulate the amount of water in the body and conserve proteins, electrolytes, and other substances that the body can reuse. Any element that is not required is eliminated in the urine, moving from the kidneys through ureters to the urinary bladder and then via the urethra and out of the body. Urine is generally yellow and a relatively clear solution. Each time an individual urinates, the quantity, color, concentration, and compounds of the urine will be slightly different because of varying constituents.

 

Many illnesses may be detected in their early stages by recognizing substances that are typically present in the urine or by estimating abnormal levels of certain substances. Some examples include glucose, protein, bilirubin, red blood cells, white blood cells, crystals, and bacteria. They may be present because of any kidney disorder or urinary tract infections. Whenever there is an elevated level of the substances in the blood, the body responds by trying to eliminate the excess through urine.

 

A complete urinalysis comprises of three distinct testing phases:

1. Visual examination - evaluates the urine's colour and clarity.

2. Chemical examination - determines the chemical properties of urine, such as its concentration, compounds present in it, and provide valuables information about health or  disease.

 

3. Microscopic examination - identifies and enumerates the type of cells, crystals, and other components such as bacteria and mucus present in urine.

 

Purpose of urinalysis

 

The urinalysis is a combination of screening tests that can detect some common diseases. It may be used in the screening and diagnosis of conditions such as UTI, kidney disorders, liver problems, diabetes, or other metabolic conditions.

 

A urinalysis can detect abnormalities that might require follow-up investigation and additional testing. A substance such as protein or glucose may begin to appear in the urine before an individual is aware of the upcoming problem.
In people diagnosed with diseases or conditions, such as kidney disease or diabetes, the urinalysis may be used in co-occurrence with other tests, such as urine albumin, to follow treatment.

 

Why is the test done?

A urinalysis is a common pathology test that is done for several reasons, such as:

 

To evaluate overall health: Urinalysis may be advised as a part of a routine check-up, pregnancy test, pre-surgery preparation, or admitting in the hospital to screen for a variety of disorders, such as diabetes, kidney, and liver disease.

 

To diagnose a medical condition: A healthcare provider may recommend a urinalysis test if an individual is experiencing abdominal pain, back pain, frequent or painful urination, blood in the urine, or other urinary problems. The test may help diagnose the cause behind these symptoms.

To monitor a medical condition: A doctor may recommend urinalysis on a regular basis to monitor the condition and treatment if a person has been diagnosed with a medical condition, for example, kidney disease or a urinary tract disease.

 

[These are suggestions only and not restricted to the above points]

 

Results

For a urinalysis, a urine sample is evaluated in three ways: visual exam, dipstick test, and microscopic exam.

 

Visual exam - A lab technician or pathologist examines the urine's appearance. Urine is typically clear. Cloudiness or an unfamiliar odor may indicate a problem. Bloody urine may make it look slightly red or brown. Urine color can also be influenced by what the patient has eaten.

 

Dipstick test - A thin plastic stick with strips of chemicals is kept in the urine sample to find abnormalities. The chemical strips changes color if certain constituents are present or if their levels are not average. A dipstick test may be used for the urine examines for the following:

 

1. Acidity (pH): The pH level indicates the quantity of acid in urine. Abnormal pH levels might be an indication of kidney or urinary tract.

2. Concentration: A measure of concentration, or specific gravity, shows how concentrated particles are in the urine. A higher than average concentration often is a result of not drinking enough fluids.

3. Protein: Little increases in protein in the urine usually are not a cause for concern, but higher protein amounts may indicate a problem such as kidney problem.

4. Sugar: Normally, the amount of sugar in the urine is too low to be detected. Any detection of glucose in this test may suggest for a diabetes test.

5. Ketones: As with sugar, any traces of ketones detected in the urine sample could be a sign of diabetes and may need follow-up testing.

6. Bilirubin: Bilirubin is a product formed when red blood cells breakdown. Bilirubin is usually carried in the bloodstream and passes into the liver, where it's eliminated and becomes part of bile. Bilirubin in the urine may indicate liver damage or disease.

 

7. Indication of infection: If either nitrites or leukocyte esterase - a product of WBCs is detected in urine, it may be a sign of a urinary tract infection.

 

8. Blood: Blood in the urine requires additional testing as it may be a sign of kidney damage, an infection, kidney or bladder stones, kidney or bladder cancer, or blood disorders.

 

Microscopic exam - During this exam, few drops of urine are viewed under a microscope. If any of the following are detected in above-normal levels, additional testing may be crucial (as recommended by doctors):

 

• White blood cells (leukocytes) in the urine may be a sign of an infection
• Red blood cells (erythrocytes) may be an indication of kidney disease, a blood abnormality, or another underlying medical condition.
• Bacteria or yeasts may indicate an infection.
• Casts - tube-shaped proteins that may form as a result of kidney disorders.
• Crystals - form from chemicals in urine may be a sign of kidney stones.

 

[Always take an advice of your physician or doctor to understand your test methods and results. This article provides suggestions only.]

 

Sources:
https://www.mayoclinic.org/tests-procedures/urinalysis/about/pac-20384907
https://labtestsonline.org/tests/urinalysis