Urine analysis has been used for thousands of years and continues to be one of the powerful diagnostic tools in medicine.
Formed by kidney urine is one of the main excretory products of your body. Normally urine consists of water and most of the metabolic waste products of your body. And with the production of about 1000 ml to 1500 ml of urine per day, a lot of things can be noted and identified about a person’s health from his urine.
There are 3 major parts of the examination of urine:
Physical Examination
The Physical examination includes the things which you can observe physically. In this examination, we look into colour, volume, odour, clarity, specific gravity.
Chemical Examination
The Chemical examination includes a test for the presence of abnormal substances or chemical in urine or abnormal amount of normal substance in urine. In this examination, we check for protein, glucose, ketone bodies, Blood and haemoglobin, Bilirubin, Bile salts and urobilinogen. Here, each test has its own significance.
Microscopic Examination
In Microscopic examination, a sample of your urine is kept under a microscope for examination. This test checks for the presence of cells from the urinary tract, blood cells, crystals, bacteria, parasites and tumours cells.
In this article, we will discuss the physical features of urine.
Physical examination for urine analysis.
Colour of urine:
- Straw-yellow/Amber colour: It is the normal colour of urine due to the presence of urochrome in the urine.
- Strong deeper colour(more orange): This may be due to dehydration, copious sweating and low fluid intake. You should load water into your system in this condition.
Dark urine along with pale stool and yellow skin and eyes may be an indication for liver disease. - Pale colour: Due to Increased fluid intake.
- Red or pink: This could be due to the presence of blood, haemoglobin, medications, beets in your urine.
Blood: Presence of blood in the urine (hematuria) is not a good sign and you should go for a check-up immediately. Generally, Urinary Tract Infection (UTI), Kidney and Bladder stones, tumours, an enlarged prostate can cause hematuria.
Beets, blackberries and rhubarb can also turn urine pink.
Medications: Rifampicin ( an antibiotic to treat tuberculosis) can turn your urine reddish-orange - Port-wine colour: Presence of Porphyrin in the urine. In a condition called porphyria and requires medical attention.
- Brownish- Black: Presence of melanin in the urine. Happens in a pathological condition called alkaptonuria.
- Brown: Presence of Bilirubin or in the urine. Bilirubin in urine suggests liver disorders.
- Orange: It suggests the presence of a small amount of bilirubin in the urine.
- Greenish: Presence of Biliverdin in the urine. It also shows a liver disorder.
- Milky White: Presence of Chyle in Urine. It is a condition called chyluria.
Clarity of urine:
In normal conditions, the urine is clear and doesn’t contain any turbidity.
Cloudy urine: Urine may be cloudy due to the presence of pus or white blood cells form a Urinary tract Infection.
If any deposit is visible in urinary sediments it could be phosphates when urine is alkaline and uric acid or urates when it is acidic. Urates dissolve in potassium Hydroxide and phosphates dissolve in acetic acid.
The odour of Urine:
Urine doesn’t have a strong odour normally but can give strong ammonia smell when concentrated. Consumption of certain substance may have characteristics changes in odour and colour of urine Eg: asparagus.
In Urinary Tract infection urine can be foul-smelling.
In Uncontrolled Diabetes urine, may have a sweet scent.
The volume of Urine:
The average volume of urine ranges forms 1000ml to 1500 ml.
Oliguria: It is a condition when urine is less than 400ml in 24 hours.
Conditions causing Oliguria.
- Less consumption of water.
- Dehydration ( See our article on Dehydration)
- Trauma
- Infection
- Urinary Tract Obstruction
- Medication
Anuria: It is a condition when there is almost no urine(<50ml) in 24 hours.
The conditions causing anuria.
- Kidney failure
- Kidney stones
- Tumours
- Heart Failure
- Hypertension
Polyuria: It is a condition where urine output is greater than or equal to 2.5 litres in a day.
Conditions causing Polyuria.
- Increased water intake ( completely normal)
- Taking diuretics (the group of drugs that increases urine production)
- Uncontrolled Diabetes Mellitus
- Primary polydipsia ( increased thirst)
- Diabetes insipidus
The Specific Gravity of Urine
The normal specific gravity of urine is about 1.002 to 1.035. It is slightly heavier than water. It is measured with a urinometer.
Generally increased density shows dehydration.
In later articles, we shall discuss the chemical and microscopic examination of urine.
And do give a look at our other article related topic urine analysis:
