0

Urobilinogen in urine

Bilirubin reduction results in the formation of a colorless substance known as urobilinogen.

The liver is one of the most important organs of the body and primary performs the essential function of maintaining blood sugar levels in the body. It is responsible for the production of a digestive juice called bile, which helps in the digestion of ingested food. The degradation of red blood cells results in the development of a byproduct called bilirubin. A yellowish pigmented waste is left by the wayside, when red blood cells die. This waste is bilirubin. Red blood cells decomposition happens in the liver, and therefore the liver is responsible for elimination of bilirubin through the urine and feces.

Sponsored link

Most of the urobilinogen produced due to bilirubin action is excreted, while a part of it is reabsorbed and put back into circulation. It is then finally eliminated as urobilinogen in urine. This completes the ‘enterohepatic urobilinogen cycle’.

Hemolysis results in the formation of excessive quantities of bilirubin. This causes increased levels of urobilinogen to form in the gut. The presence of hepatitis and other liver conditions results in the interruption of ‘intrahepatic urobilinogen cycle’, leading to an increase in the levels of urobilinogen. This is then transformed into a yellowish product known as urobilin, which gives the urine its yellow color. Urobilinogen, which is present in the intestines, undergoes oxidation to form brown colored stercobilin, causing the characteristic color of the fecal material.

Biliary obstruction leads to diminished quantities of bilirubin in the intestine. This results in lowered amounts of urobilinogen. Consequently, lowered amounts of urobilinogen are then available for re-absorption and elimination, which results in lowered urobilin content in urine. Also, excessive quantities of bilirubin can be found in circulation, which are then finally excreted through the kidneys. Such irregularities result in the formation of pale feces and pigmented urine during biliary obstruction.

Treatment with a wide variety of antibiotics as well as full obstructive jaundice can result in the destruction of bacterial present in the intestines. This can prevent the passage of bilirubin into the gut or cause absent or diminished production of urobilinogen in the gut, eventually leading to low urobilinogen in urine.

Low levels of urobilinogen in urine can also result from medications such as ascorbic acid or ammonium chloride, that increase the urine acidic content; or due to congenital enzymatic jaundice.

The presence of disorders such as hemolytic anemia or increased degeneration of red blood cells, limited liver function, overuse of the liver, hepatic infection, excessive manufacture and re-absorption of urobilinogen, liver cirrhosis and poisoning can result in increased levels of urobilinogen in urine

Urobilinogen in urine test

The ‘urobilinogen in urine test’ is an effective way to diagnose liver abnormalities. The urobilinogen levels along with bilirubin levels are used to detect and differentiate between various types of jaundice.

The test is conducted using paper strips that have stable diazonium salt. The test produces a red colored azo compound when there is contact with urobilinogen.

Evaluation of the test:

  • The color of urine is used to diagnose the presence of urobilinogen in urine. The normal elimination rate of urobilinogen in urine is considered to be 1 mg urobilinogen/dL urine. Normal concentration of urobilinogen in urine is low {0.2-1.0 mg/dL  or  < 17 micromol/L}
  • A lower than normal level or higher than normal level or a complete lack of urobilinogen in urine is deemed as pathological. However, it is important to note that absence of urobilinogen in urine cannot be detected by the use of such strips.
  • The different combinations of colors in the test strips are an indication of the concentration of urobilinogen in urine. A lab agent would be in a better position to evaluate the results of the test.
  • It is also important to note that excessive formaldehyde concentration in urine can yield false or no results; exposure of the urine sample to prolonged periods of light can yield false negative or inhibited results; the presence of therapeutic or diagnostic dyes can yield false positive or higher than normal results; and excessive quantities of bilirubin can result in increased yellow color of urine.

The diagnosis of urobilinogen in urine:

  • Increased concentration of urobilinogen in urine does indicate the presence of hemolytic disorders and liver abnormalities. Excessive levels of urobilinogen in urine can indicate chronic or viral hepatitis, poisoning, liver cirrhosis, pernicious or hemolytic anemia, infection, polycythemia, liver carcinoma or congestion and irregularities of the intestinal tract.

Urinalysis

Urinalysis is another way to detect the presence of urobilinogen in urine. In this procedure, the urine may be taken in two ways, at the bedside or dipstick or in a laboratory. The lab procedure can involve various aspects such as evaluating urinary electrolytes, culture of urine sample, microscopic observation, sensitivity readings, etc. It is important to note that urine samples used for detection of ‘urobilinogen in urine’ levels are prone to contamination and hence should be transferred at the right temperature and in a timely manner.

Sponsored link
Filed in: Medical Tests Tags: , , ,

Get Updates

Share This Post

Related Posts

Leave a Reply

Submit Comment

© 2017 See Ya Doctor. All rights reserved.