Why is urine analysis done?

Urine analysis is done to detect the following:

1. To detect the presence of blood (Hematuria) or protein (protein urea) in the urine.
2. To detect presence of pyuria (Increased number of WBC’s).
3. To identify crystals in the urine which may be seen in stones.
4. To identify casts. Due to damage to the kidney proteins, shed tubular cells, RBC’s, WBC’s aggregate and get molded as they pass through the kidney and are seen as casts in the urine.

What is the significance of urine color?

The urine is normally light yellow in color. Change in the color of urine is seen in the following conditions:

1. Dark colored urine: Seen when water intake is less or conditions like dehydration. Usually seen after excess sweating, as in exercise and more commonly in summer.
2. Brownish color of urine: Seen when there is small amount of blood in urine. Called smoky urine. Seen in glomerulonephritis. It is accompanied by swelling of feet and decreased urine and maybe fever.
3. Very dark yellow urine: Seen in jaundice. Accompanied by symptoms such as pain in the abdomen, nausea and fever.
4. Many drugs e.g. Rifampicin, or ingestion of vegetables like beet root can make the urine look orange.
5. Whitish discoloration when accompanied by burning urination seen in urinary tract infection.
6. Frank red color is called hematuria.

What is Proteinurea?

Increase urinary excretion of protein is called as protein urea. Normal excretion of urine protein is less than 150 milligrams/ 24 hours for adults. Anything in excess of this is called as protein urea.

How is Proteinurea detected?

This urine protein is detected by a test which is called as dipstick and it depends on the ability of proteins specially albumin to alter the color reaction of a pH sensitive dye (tetrabromophenolpthalein) on a plastic strip. The Proteinurea is quantified as follows:
1+: Approx 30mg/dl
2+: 30–100mg/dl
3+: 100–500mg/dl
4+: > 2000mg/dl