What is a urinalysis?
A urinalysis is simply an analysis of the urine. It is a very common test that can be performed in many healthcare settings including doctors' offices, urgent care facilities, laboratories, and hospitals.
It is performed by collecting a urine sample from the patient in a specimen cup. Usually only small amounts (30-60 ml's) may be required for urinalysis testing. The sample can be either analyzed in the medical clinic or sent to a laboratory to perform the tests. Urinalysis is abbreviated UA.
Urine can be evaluated by its physical appearance (color, cloudiness, odor, clarity), or macroscopic analysis. It can be also analyzed based on its chemical and molecular properties or microscopic assessment.
Urinalysis is ordered by doctors for a number of reasons, as follows:
- Routine medical evaluation
General yearly screening, assessment before surgery (pre-operative assessment), admission to hospital, screening for kidney disease, diabetes mellitus, hypertension (high blood pressure), liver disease, etc.
- Assessing particular symptoms
Abdominal pain, painful urination, flank pain, fever, blood in the urine, or other urinary symptoms.
- Diagnosing medical conditions
Urinary tract infection, kidney infection, kidney stones, uncontrolled diabetes (high blood sugars), kidney impairment, muscle breakdown (rhabdomyolysis), protein in urine, kidney inflammation (glomerulonephritis).
- Monitoring disease progression and response to therapy
Diabetes related kidney disease, kidney impairment, lupus related kidney disease, blood pressure related kidney disease, kidney infection, protein in urine, blood in urine.
What can urinalysis results show?
Urinalysis can disclose evidence of diseases, even some that have not caused significant signs or symptoms. Therefore, a urinalysis is commonly a part of routine health screening.
Urinalysis is commonly used to diagnose a urinary tract or kidney infection, to evaluate causes of kidney failure, to screen for progression of some chronic conditions such as diabetes mellitus and high blood pressure (hypertension).
It also may be used in combination with other tests to diagnose some diseases. Additional tests and clinical assessment are often required to further investigate findings of urinalysis and ultimately diagnose the causes or specific features of underlying problems. For example, urine infection is generally diagnosed based on results of urinalysis. However, urine culture is often ordered as a follow-up test to identify the bacteria that may be causing the infection. Other examples include kidney stomes, inflammation or the kidneys (glomerulonephritis), or muscle breakdown (rhabdomyolysis).