Bilirubinuria

As bilirubinuria refers to the excretion of bilirubin through the urine . Bilirubin is a breakdown product of heme , the central building block of the red blood pigment . If the concentration of direct ( conjugated ) bilirubin in the blood exceeds 0.5 mg / dl (8.5 µmol / l), it is excreted in the urine and causes a brownish-yellow color in the urine.

Since unconjugated (indirect) bilirubin is not excreted via the urine, a bilirubinuria for discriminating a through may blood decay caused jaundice ( praehepatic jaundice ) from one caused by a liver disease or bile outflow obstruction ( hepatic and posthepatic jaundice be used). Prehepatic jaundice does not go along with bilirubinuria.

The detection of bilirubin can be done semiquantitatively with a urine test strip . False negative results can occur if the urine has stood still for a long time or has been exposed to sunlight, as this oxidizes bilirubin to biliverdin . In addition, larger amounts of ascorbic acid or nitrite can reduce the detection sensitivity.

literature

• Katharina Müller: Original exam questions with commentary class 2, clinical chemistry . Georg Thieme Verlag, 2002, ISBN 9783131125958 , p. 134.

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !