Urine
Urine screening
Laboratory screening of ten urine parameters, including protein, glucose, blood cells, nitrite, pH and specific gravity. You collect the sample at home.
€ 35,00
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Urine tests · Urine
Bilirubin
Bile pigment in the urine; normally not detectable, a positive result may point to a problem of the liver or bile ducts.
At a glance
- Measured in urine
- In 1 test panel
- Check the preparation
Explanation
Bilirubin: what is measured?
Bilirubin is a yellow breakdown product of red blood cells. The liver links it to a sugar group (conjugated or direct bilirubin) and excretes it via the bile. Only this linked bilirubin can reach the urine via the kidneys, and that only happens when it is raised in the blood. In healthy people, bilirubin is not detectable in the urine.
What can it detect?
- Inflammation or damage of the liver, for example due to a virus, alcohol or medicines
- Blocked bile drainage, for example due to gallstones
Result
What does the result mean?
Positive result
Bilirubin in the urine fits a raised conjugated bilirubin in the blood. This is usually caused by liver inflammation (hepatitis), liver damage from alcohol or medicines, or a blockage of the bile ducts by gallstones. The urine is then often dark, like cola or strong tea, sometimes with yellow eyes or skin, itching and pale stool. Rarely: a narrowing of the bile ducts due to a tumor. Some medicines that color the urine give a false positive result.
Negative result
A negative result is normal. A raised bilirubin due to Gilbert's syndrome or the breakdown of red blood cells does not cause bilirubin in the urine, because that bilirubin is not yet conjugated. Light and standing for a long time break down bilirubin, and vitamin C suppresses the reaction; a negative dipstick therefore does not rule out a liver problem. Blood tests are much more sensitive for the liver.
After an abnormal result
With a positive result, blood tests for bilirubin and liver values (ALT, alkaline phosphatase, gamma-GT) follow. Depending on the results, tests for viral hepatitis or an ultrasound of the liver and bile ducts follow.
Reliability
How reliable is the test?
A urine dipstick is a quick screening and not a diagnosis. According to the Dutch GP guideline (NHG) on urinary tract infections, the dipstick is a first step with symptoms that fit a bladder infection; if in doubt, a culture or sediment test follows. For detecting kidney damage, the dipstick is less sensitive than the albumin-creatinine ratio in urine and the eGFR in blood; the NHG guideline on chronic kidney damage is based on those. In people without symptoms, most abnormal dipstick results are temporary or harmless; a single abnormal result therefore says little.
What can affect the result?
- Sample collection: preferably use first morning urine or urine that has been in the bladder for at least 4 hours, and after washing, catch the middle part of the stream (midstream), so that no discharge or skin bacteria get into it.
- Menstruation, and the days before and after it, often gives a positive result for blood and sometimes for leukocytes and protein; it is better to collect at another time.
- Vitamin C (supplements or a lot of fruit juice) can suppress the reaction for blood, glucose, nitrite and bilirubin and give a false negative result.
- Heavy exercise, fever and dehydration in the day before sample collection can temporarily cause protein, blood or ketones. Urine that has been standing for a long time or has become warm gives less reliable results, especially for nitrite, bilirubin, urobilinogen and pH.
Preparation
- Preferably use the first morning urine, or urine that has been in your bladder for at least 4 hours.
- Collect the middle part of the stream.
- Do not collect urine during your period.
Who it is for
Who is the test useful for?
Useful for
Useful with symptoms that may fit a bladder infection, such as frequent and painful urination, or as a simple addition to blood tests for the kidneys, sugar or liver. For detecting kidney damage in diabetes or high blood pressure, the albumin-creatinine ratio in urine says more than the dipstick. In people without symptoms and without risk factors, the chance of a harmless abnormality is greater than the chance of a real condition.
How common is it?
Bladder infection is one of the most common infections in women; in men it is much less common. Chronic kidney damage occurs in about 1 in 10 adults, usually without symptoms. In people without symptoms, an abnormality on the dipstick is found in some, usually without a serious cause.
NHG guideline on urinary tract infections; NHG guideline on chronic kidney damage
Get tested
Bilirubin: test panels
Bilirubin is part of these test panels. You order online and have your blood drawn at a collection point or collect the sample at home.
Evidence
Sources
This explanation is based on Dutch guidelines and independent information. It is general information, not a diagnosis. Discuss an abnormal result with your GP.
More about risks and resultsMore explanations
Other tests: Urine tests
- Erythrocytes and free hemoglobin
- Glucose
- Ketones
- Leukocytes
- Nitrite
- pH
- Protein
- Specific gravity
- Urobilinogen