Bilirubin in the urine - what does it mean ?
Analyses And Studies / / August 12, 2017
- Why bilirubin appears in the urine?
- Elevated bilirubin in urine, what does it mean?
Why bilirubin appears in the urine?
After destruction of erythrocytes are destroyed its main component - hemoglobin consisting of the porphyrin and the protein.Subsequently converted to porphyrin unconjugated bilirubin, which enters the liver and it is connected with glucuronic acid.As a result, it becomes bound bilirubin.Next conjugated bilirubin in the bile enters the lumen of the intestine, where the actio
Some derivatives of bilirubin re-absorbed from the intestine into the blood and is captured by the liver for recycling.And only a minor part is eliminated in the urine of a healthy person is no greater than 4 mg / day.Such an amount of bilirubin is below the threshold sensitivity of the laboratory methods for its quantification.Therefore, the norm for the analysis of urine - the absence of bilirubin and its metabolic products, which are called urobilin.In most cases, used for determining urobilin urinalysis for bile pigments.
Elevated bilirubin in urine, what does it mean?
Intermediate bilirubin metabolism products that fall into the urine, called urobilinoidami.They include uorobilinogen, urobilin and urobilinoidnye connection.It urobilin urine stains, normally it is light yellow or straw-yellow color.The higher concentration of urobilin in the urine, the darker and richer the color.
most often in the urine increased bilirubin due to liver function abnormalities responsible for detoxification.The failure of the liver detoxification abilities developed for diseases that lead to massive loss of hepatocytes.The free bilirubin resulting from its metabolism intermediates in large quantity is accumulated in the blood and urine starts to be output.The most common causes of this condition, the following diseases:
- acute viral hepatitis (90% of A or B);
- toxic hepatitis (poisoning hepatotoxic poisons);
- alcoholic hepatitis (alcoholism);
- infectious diseases accompanied by lesions of hepatocytes: leptospirosis, mononucleosis, brucellosis, etc .;
- hepatotoxicity (overdose of antibiotics, steroids, etc.);
- during pregnancy in the later stages, some women can develop cholestatic hepatitis;
- chronic hepatitis (usually viral);
- liver tumors;
- biliary cirrhosis.
Besides the diseases causing the death of liver cells, the appearance of bilirubin in the urine cause a condition in which there is increased formation of bilirubin.In most cases, this situation occurs in the development of hemolytic anemia, accompanied by severe jaundice.Liver function in this pathology are not violated, because of the volume of the resulting bilirubin hepatocytes are unable to process it, which leads to bilirubinuria.Most often it occurs in the following diseases:
- hemolytic anemia innate nature (thalassemia, sickle cell, and others.);
- infectious nature of the disease, for which there is a mass destruction of red blood cells (sepsis, malaria);
- hemolytic disease (developing a child's first days of life as a result of incompatibility with maternal blood);
- hemolytic anemia caused by poisoning (heavy metal salts, aniline dyes, plant and animal poisons);
- increased hemolysis due to the use of drugs;
- autoimmune hemolytic anemia (the formation of the immune system antibodies to their own red blood cells);
- consequence of major injuries, accompanied by massive bleeding in the tissue or body cavity (fractures of the pelvis, the large tubular bones with damage to the arteries).
Determination of bilirubin in urine is of great informative value in the diagnosis of the conditions listed above.Application of the method allows:
- early diagnosis of hepatitis;
- mechanical differential diagnosis of jaundice and liver (in violation of the outflow of bile bilirubin in urine is absent);
- reliably judge the functional state of the liver (bilirubin in the urine of 17 mmol / L indicates a serious liver disease).
12 Aug, 2017
12 Aug, 2017