The urinalysis test is used to detect various compounds that are eliminated in the urine, as well as cells, including bacteria, and cellular fragments.
Urine is produced by the kidneys as product of filtering wastes and metabolic byproducts out of the blood. Anything that is not needed is excreted in the urine. Urine is generally yellow and relatively clear, but color, quantity, concentration, and content of the urine can be slightly different because of varying constituents.
Many disorders can be diagnosed in their early stages by detecting abnormalities in the urine.
A complete urinalysis consists of:
1. physical examination : urine's color, clarity, and concentration
2. chemical examination, which tests chemically for 9 substances that provide valuable information about health and disease
3. microscopic examination, which searches and counts the type of cells, casts, crystals, and other components (bacteria, mucus ) that can be present
Its concentration is measured by means of analysis of a urine sample.
Purpose of the test
To detect the presence of some possible substances in the blood in order to give a first alert for many possible problems. For example to screen for metabolic and kidney disorders and for urinary tract infections.
This test is done during a routine physical or when there are symptoms of a urinary tract infection, such as abdominal pain, back pain, frequent or painful urination, or blood in the urine. Also as part of a pregnancy checkup, a hospital admission, or a pre-surgical work-up.
Reference range values
Protein = Negative
Glucose = Negative
Ketones = Negative
Hemoglobin = Negative
Urobilinogen = Negative
Leukocyte Esterase = Negative
Nitrite = Negative
pH = 5-8 (fasting)
Specific Gravity = 1.002-1.035
RBC's 0 - 15/mcL
WBC's 0 - 25/mcL
Abnormal results can mean that something is wrong and need to be further evaluation. But the results do not tell exactly what the problem can be.
Also a normal result does not mean that there is no illness.