Urine Bilirubin

Bilirubin testing on the Urine Dipstick reflects tests for 2 different related compounds
Conjugated Bilirubin
1. Unconjugated Bilirubin is not soluble in water and is not found in the urine
2. Conjugated Bilirubin is excreted in the stool under normal conditions
3. Conjugated Bilirubin is an abnormal finding in the urine and reflects liver disease (or False Positive)
4. Ictotest can be run as a confirmatory test for urine Conjugated Bilirubin
Urobilinogen
1. Relatively small amount of Bilirubin is converted to Urobilinogen in the intestinal tract and renally excreted
2. Large amounts of Urobilinogen suggest hepatic disease or Hemolysis

True Positive Test
1. Biliary tract obstruction
2. Hepatitis
  1. Viral Hepatitis
  2. Toxic Hepatitis
  3. Drug Induced Hepatitis
Confirmatory Findings of Positive Test
1. Ictotest Positive
2. Gross urine findings if Conjugated Bilirubin present
  1. Dark Urine with yellow foam
  2. Sediment elements may be stained
False Positive Bilirubin (Ictotest Negative)
1. Chlorpromazine (Thorazine)
2. Phenazopyridine (Pyridium)
False Negative Bilirubin
1. Selenium
2. Vitamin C
3. Prolonged light exposure

True Positive Urobilinogen
1. Trace or Small Urobilinogen may be a normal finding
2. Hepatitis
3. Liver disease
  1. Cirrhosis
  2. Liver Metastases
  3. Liver infarction
4. Hemolytic Jaundice
False Positive Urobilinogen
1. Phenazopyradine (Pyridium)
2. Sulfonamides
False Negative Tests
1. Inadequate urine sample storage
2. Preservatives present in urine sample