What exactly is urine?
urinary pH is produced by the kidneys by filtering out the waste from the bloodstream which
helps in regulating the amount of water in the body, conserving proteins, electrolyte,
and other compounds that the body can use again. Anything that is not needed by the
body is eliminated in the urine, which is usually clear and yellowish in colour, but the
colour, quantity, concentration, and content of the Urine will be slightly different each
time an individual urinates, due to varying constituents. Many illnesses and disorders
associated mostly with the main excretory organ i.e. kidneys, affect this process of
elimination, which in turn affects the appearance, concentration, and content of your
urine. Therefore, urine testing can aid in the early diagnosis of such disorders.
What is urinalysis?
Urine testing, often referred to as "urinalysis" (urine analysis) is a simple Pathology Test
that examines a small sample of your urine. It is used to diagnose and monitor a wide range
of disorders including kidneys such as infections, chronic kidney disease, acute kidney
failure or kidney stones, urinary tract infections, liver disease and diabetes.
Why is urine testing important?
urine microscopy test can be performed for several reasons as below:
- Asessing the overall health as a part of a routine medical exam, pre-surgery preparation,
pregnancy checkup, or on hospital admission to screen for a variety of disorders such as a
kidney disease or liver disease.
- To identify the cause of symptoms like abdominal
pain, back pain, painful or frequent urination,
blood in urine and can aid in the early diagnosis of disorders.
How do you give a urine sample?
Although, urine can be collected at any time of the day, in some cases, a first morning sample may be
requested as it is more concentrated and more likely to detect abnormalities. Urine collection
usually utilizes the "clean-catch" technique, which helps prevent bacteria from the external
genital surface from contaminating the sample and interfering with the test results interpretation.
In this technique, the urethra is initially cleaned with water, a few drops of urine are discarded
and 30-60 ml of midstream urine is then collected in the sterile container provided. After urine
collection, the lid should be closed carefully and touching the inside of the cup should be avoided
to prevent contamination. In some cases, it is suggested to use a catheter inserted in the bladder
for urine collection which may cause mild discomfort.
Is fasting required for urine test?
No fasting is required before a urine test but the consumption of food that could discolour the
urine like beet and food dyes could be avoided before taking the test. It is advised to
let the doctor know about all the medications or supplements you are taking beforehand
as some drugs might affect the urinalysis results.
Drinking sufficient amount of water
before the test is essential, so that an
adequate amount of urine sample can be collected for accurate results.
However, drinking excessive amount
of water may lead to inaccurate
results and should be avoided.
What are the types of urine test?
1. Urinalysis
It consists of specific physical, it chemical and microscopic tests that detect the presence
or/and measure abnormal levels of several substances in the urine, such as byproducts of
normal and abnormal metabolism, cells, cellular fragments, and bacteria that might help
in early detection of certain disorders or illnesses. A healthy kidney does not allow proteins
like urine to pass into the urine but when the kidneys are damaged, it may allow some
proteins to leak into the urine which is one of the earliest signs of a kidney disease.
Visual Examination: It involves the visual (macroscopic) examination of the urine
sample for colour, clarity and for various abnormalities like:
Clouded appearance-Indicates an infection
Reddish/brownish appearance Indicates the presence of blood in the urine
Foamy appearance- Indicates kidney disorders
Abnormal odours
Dipstick Test: It involves using a dipstick, i.e. a thin plastic strip
treated with chemicals which is dipped into the urine sample to detect abnormalities
in its chemical composition. A change in the colour of the dipstick indicates that certain
substances are present at a level that is above normal. It not only reveals the presence
of a substance, but also estimates how much of the substance is present.
Some of the parameters of a dipstick examination can check for include:
Acidity (pH)-An abnormal pH may
be a sign of kidney stones, chronic kidney disease, urinary infections,
or other disorders.
Protein- Abnormally high protein
levels may be indicative of a kidney problem
Glucose or ketones- A high sugar
content or ketones is a marker for diabetes.
WBCs (pus cells).These are signs of infection or inflammation, either
in the kidneys or anywhere else along urinary tract.
Bilirubin (a product of RBC
breakdown)-Its presence may
indicate liver damage or disease.
Blood- It may be a sign of an infection, kidney damage, kidney or bladder stones, kidney
or bladder cancer, blood disorders, etc. However, it can also be caused by certain medicines, or
even heavy exercise
Nitrites or leukocyte esterase
(product of WBCs)- It is indicative of an infection with certain kinds of bacteria or
urinary tract infection.
Microscopic Examination: It involves examining a small amount of
urine under a microscope to check, identify and measure the substances that are usually
absent in normal urine such as:
WBCS-It may indicate an infection
or inflammation in the kidneys,
bladder or other areas.
RBCS- It may be a sign of kidney
disease or kidney stones, infection, a blood disorder (like sickle cell disease)
or another underlying medical condition (like bladder cancer).
Bacteria or yeasts. It may be indicative of an infection in the body.
Casts (tube-shaped proteins)- developing a kidney disease, such as They
may form as a result of kidney diabetes or high blood pressure. disorders.
Crystals (clumps of minerals)
They form from chemicals in the
urine and may be a sign of kidney
stones.
The sample might be sent for a urine culture if the dipstick test
or the microscopic examination shows
any abnormality, in order to identify the microorganism that may be causing
the infection. Several factors like diet, dehydration, medicines,
exercise, etc., can affect the result of urinalysis
and one might be asked to produce a
fresh sample in such cases.
2. Albumin-to-Creatinine Ratio (urine) or Microalbuminuria tests
ACR test helps to measure the levels of albumin (protein in the blood) in the urine.
It measures and compares the amount of albumin with the amount of creatinine in the urine
sample and if excess amount of albumin (>30mg/g) is found to be
eliminated in the urine, it may be a indicative of a kidney disease. Albumin levels can also
rise in case of excessive exercise, high blood sugar
or bladder infections. Being more sensitive, Microalbuminuria test can
be used to detect traces of albumin in urine and is usually suggested for
patients having a higher risk of
3. Creatinine Clearance Test
a 24-hour sample of urine.
is a waste product formed in the body stones.
from daily use in the muscles.
amount of creatinine in the urine
sample is compared to the levels of
kidneys in the blood which
indicates how much waste the
kidneys are filtering out each day and the
the overall heath of the kidneys.
Urine analysis might not answer all
the questions about one's health as it
does not provide a definitive
diagnosis, but it provides various
clues on the body's condition and
health status of various organs of the
body, especially the kidneys. An
unusual urinalysis report can lead to
more tests to understand the root of
the problem and therefore, can help
to detect various kidney disorders at
an earlier stage, before the
symptoms start to appear. Early
diagnosis would prove to be useful in
Successfully treating a serious
condition such as kidney damage or
kidney stones before it worsens.
Hence, if you are asked to "pee in the
cup" the next time, you now know
how it is related to your kidney's
health!
