Routine urine examination is detailed analysis of urine. It helps detect alterations in the composition of the urine which help in the diagnosis of many disorders.
When a sample of urine is submitted to a pathological laboratory, the following examinations are done:
Physical Examination
Volume
- Normal volume of an early morning mid–stream sample is 50 – 300ml.
- If it is more than 500ml, it indicates diabetes or polyuria (frequent passing of urine).
- If it is less than 20ml, it indicates some kidney disorder.
- The normal color of urine is pale yellow.
- If it is dark yellow to orange, it indicates some liver disorder.
- If it is white, it shows the presence of pus.
- If it is pink to red, it indicates the presence of red blood cells.
- If it is brownish black, it indicates the presence of melanin or homogenistic acid (a rare disorder).
- If it is blue to green, it is a liver disorder.
Appearance
- Usually, it is clear, sometimes, it is cloudy.
- Sometimes, it is turbid due to the presence of WBCs (White Blood Cells), epithelial cells.
- Sometimes, it is hazy due to mucus.
- Smoky, due to red blood cells.
- Milky due to chyle (lymph).
- Usually acidic pH range 4.5 – 7.5.
- If pH less than 4.7 it is more acidic.
- If pH more than 7.5 it is more alkaline.
- Usually, it is aromatic in normal conditions.
- It has a fruity odor in diabetes.
- Ammoniacal odor in cases of urine retention.
- Foul smelling due to urinary tract infection.
- Usually, there is no or very little formation of sediment in normal conditions.
- If pus cells, red blood cells, cysts or epithelial cells are present, the sedimentation rate ranges from moderate to high.
- Usually varies from 1.003 to 1.060.
- A low special gravity indicates diabetes insipidus or kidney infection (chronic).
- High specific gravity indicates diabetes mellitus or acute kidney infection.