Bilirubinuria

Q: Bilirubinuria (bilirubin in the urine) reflects? (select one) 

 A) Conjugated bilirubinemia 
B) Unconjugated bilirubinemia


Answer: A

Unconjugated bilirubin is tightly bound to albumin and is not present in the urine. Presence of bilirubin in the urine indicates conjugated bilirubinemia and probable hepatobiliary disease process. 

Clinical significance: Bilirubinuria can exist with normal serum  conjugated bilirubin as reabsorptive capacity of kidney for conjugated bilirubin is low, and it can be an early sign of liver disease.

#hepatology

Reference: 

KLATSKIN G, BUNGARDS L. An improved test for bilirubin in urine. N Engl J Med 1953; 248:712.