Urine For Bile pigments (Bilirubin, Urobilinogen, and Bile Salts)
Urine For Bile pigments
Sample for Urine For Bile pigments
- The sample is urine.
- Bile salt can be checked on random urine.
- Bile pigmetns also include bilirubin and biliverdin.
Indications of urine for bile pigments
- This is because the presence of bile pigments in the urine indicates liver dysfunction.
- The presence of bile pigments in the urine helps to diagnose the increased production of bilirubin.
Pathophysiology of the bile and bile pigments
- Bile acid and bile salts are used as synonyms.
- The bile is a fluid synthesized by the liver and consists of :
- Conjugated bile salts.
- Bilirubin diglucuronide.
- Bile is alkaline due to the presence of bicarbonate.
- Bile color is golden-brown to greenish-yellow and has a bitter taste.
- Bile acids are synthesized in the hepatocytes from cholesterol. These are excreted into the bile and then pass into the duodenum.
- The primary bile acids are:
- Cholic acid.
- Chenodeoxycholic acid.
- These primary bile acids pass into the duodenum (intestine), and the bacterial action converts to secondary bile acids.
- Secondary bile acids are:
- Deoxycholic acid.
- Lithocholic acid.
- The bile acid can conjugate with glycine and taurine and form bile salts.
- The primary bile acids are:
- Bile salts help in stimulating the bile flow and are a potent antibacterial.
- The primary bile pigments are due to catabolism of the hemoglobin are:
- Bilirubin. is orange or yellow in color.
- Biliverdin is green in color.
- Urobilinogen (Urobilin).
- The leading site of the formation of bile pigments in the liver.
- Ultimately these leave the body in feces and a small amount in the urine.
- The human bile contains:
- Cholate conjugate = 38%.
- Chenodeoxycholate conjugate = 34%.
- Deoxycholate conjugate = 28%.
- Lithocholate = 1 to 2%.
- The hepatic bile contains 5% to 15% of the solids, and the major components are bile acids.
Bile salt and bilirubin detection procedure:
- Bile pigments (Bilirubin) give the urine greenish-yellow, yellow or brown color.
- The Fouchet test detects bile pigments (Bilirubin).
- For bile salts, advise sulfur granules test.
Fouchet’s test. It will detect the bilirubin in the urine.
- Reagents are:
- Barium chloride 10%.
- Fouchet’s reagents consist of:
- Trichloracetic acid = 25 grams.
- Ferric chloride (FeCl3) 10% = 10 mL
- Distle water = 100 mL
- The procedure of Fouchet’s test:
- Take 5 ml of the urine, if the urine is alkaline then add one to 2 drops of glacial acetic acid (concentrated).
- Take 5 mL of urine and add barium chloride (BaCl2 10%) 2.5 mL.
- Mix well.
- The sample will become cloudy.
- Filter or centrifuge to obtain the precipitate which contains bilirubin.
- A precipitate of sulfates appears to which bilirubin is bound (barium-sulfate-bilirubin complex).
- To the filtrate on the paper (precipitate) adds one drop of Fouchet’s reagent (Ferric chloride).
- When ferric chloride is added to urine in trichloroacetic acid, it oxidizes bilirubin to green color biliverdin.
- Immediately blue-green color develops indicating positive for bilirubin.
|Test result||Positive for bile contents|
|There is an immediate blue-green color around precipitate||Positive for bilirubinin|
|There is no blue-green color||Negative for bilirubinin|
Foam test for bilirubin: Urine is kept in a small vial and vigorously shaken. The bile pigments will stain the resulting foam.
- There is yellowish foam in the case of urine bilirubin.
- In normal urine, the foam will be white.
Sulfur granule test for bile salts:
- Carefully sprinkle the sulfur granules over the surface of the urine.
- Also can run water as the control.
- In the case of bile salts, sulfur will settle in the bottom.
- In the case of negative urine, sulfur granules will remain over the surface.
Normally bile pigments and bile salt are absent in normal urine.
Normal urine picture:
|Physical features||Chemical features||Microscopic findings|
Questions and answers: