Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Bilirubin is primarily derived from metabolism of hemoglobin. Only conjugated bilirubin is excreted into the urine and normally only trace amounts can be detected in urine. Elevated urinary bilirubin occurs in patients with obstructive jaundice or jaundice due to hepatocellular disease or injury. However, urine bilirubin is relatively insensitive for detection of liver disease. Hyperbilirubinemia due to hemolysis is principally due to unconjugated bilirubin, and therefore does not result in increased urinary bilirubin.
Limited use in screening of patients for liver disease.
Elevated urinary bilirubin is suggestive of hepatocellular disease or post-hepatic biliary obstruction.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
False positive tests may occur if urine is contaminated with stool, or if the patient is taking drugs which cause red coloration of urine. False negative tests may occur after prolonged storage, exposure to light, or if patient has taken large amounts of ascorbic acid.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
If positive, results reported as trace or positive.
Clinical References Provides recommendations for further in-depth reading of a clinical nature
Brunzel, NA, Fundamentals of Urine and Body Fluid Analysis, W.B. Saunders Company, Philadelphia, 1994.