Bilirubin Test

Overview

The bilirubin blood test, also known as Total serum bilirubin (TSB), is used to measure the amount of bilirubin present in your blood. Bilirubin, a yellowish substance that your body makes during the normal process of removing old red blood cells, is what you call bilirubin. Bilirubin can be found in bile. Bilirubin is a fluid that your liver produces to help you digest food.

Bilirubin is then absorbed into your bloodstream and travels to the liver. The liver processes bilirubin, which is then mixed with bile and excreted into the bile ducts. It is then stored in your gallbladder. The small intestine eventually releases the bile to aid in the digestion of fats. It is eventually excreted from your stool.

The liver attaches bilirubin to glucuronic acids, a glucose-derived chemical, and this is known as direct or conjugated bilirubin. Indirect, or unconjugated bilirubin, is bilirubin that is not attached to glucose-derived acid. Total bilirubin is all the bilirubin found in your blood.

Your liver will eliminate most of the bilirubin if it is healthy. If your liver is not working properly, bilirubin could leak from your liver into your bloodstream. Jaundice is a condition where too much bilirubin can get into your bloodstream. This causes your eyes and skin to turn yellow. A bilirubin blood sample and signs of jaundice can help your doctor determine if you have liver diseases.

An accurate count of all three levels of bilirubin in your blood will be obtained by comprehensive bilirubin blood testing. High bilirubin symptoms can affect both children and adults.

Why Test Is Done?

To check your liver health, a bilirubin blood test can be used. This test is often used to diagnose newborn jaundice. Jaundice is a condition in which healthy babies develop bilirubin resistance. Jaundice in newborns is not usually dangerous and disappears within a few days. However, infants should be tested for high levels of bilirubin. This can cause brain damage in rare cases.

When To Get Tested?

A bilirubin blood sample may be ordered by your provider:

• If you experience symptoms like jaundice, dark urine, or stomach pain. These symptoms could indicate liver disease, cirrhosis, or other liver diseases. These symptoms could also be indicative of gallbladder diseases.
• You can check the tubes that carry the bile from the liver to determine if there is any blockage in your bile ducts.
• To determine if you have liver disease.
• Diagnose disorders involving the breakdown of red blood cells. A condition known as hemolytic is characterized by high blood bilirubin levels. This condition causes the body to destroy red blood cells quicker than it makes them.

Your liver may be suffering from damage if bilirubin is not being attached to glucose-derived acid (conjugated in the liver) or is not being properly removed from the blood.

It is, therefore, possible to test for liver damage by testing for bilirubin levels in the blood. Mild jaundice can occur in newborns due to normal changes in the metabolism of Bilirubin or as the first sign of a serious medical condition.

An infant may have their blood tested multiple times during the first few days to determine if the level is too high. If left untreated, jaundice can become life-threatening and very serious in newborns.

High bilirubin levels may also be since red blood cells are being killed more than usual. This is hemolysis.

Sometimes, bilirubin can be measured as part of a panel of tests. A group of tests is often used to evaluate the liver, which includes:

• Alanine Transaminase
• Alkaline Phosphatase
• Aspartate Aminotransferase
• Total protein
• Albumin

How To Get Tested?

You may be asked by your health care provider to fast for at least four hours before your blood test. Your provider will inform you if there are any special instructions.

You will be required to stop eating or drinking anything else for four hours before the test can be performed. Before you go to the laboratory or collection location, you can still drink normal amounts of water.

You may need to discontinue certain medications before the test is performed. However, only if your doctor has instructed you otherwise.

Penicillin G, sedatives such as phenobarbital, and diuretics such as furosemide, (Lasix), are just a few examples of drugs that can alter bilirubin levels. Asthma medications like Theophylline also possibly have an adverse effect.

You may also be taking other medications that could affect bilirubin levels. Before you have your test, talk to your doctor to determine if you should stop taking the medication or continue to take it.

During the Test

A small needle is used by a health professional to take blood from a vein on your arm. Once the needle has been inserted, some blood will be taken and stored in a vial or test tube. The needle may cause a slight stinging sensation when it is inserted or removed. It usually takes less than five minutes.

After The Test

You may feel a slight pinching sensation or mild pain when blood is taken. You may feel a throbbing sensation after the needle has been removed.

For the remainder of the day, you should not use that arm for lifting heavy objects.

The few mild risks that involve are:

• Lightheadedness or fainting
• Hematoma is a bruise in which blood has accumulated under the skin.
• Infection is usually prevented by washing the skin before inserting the needle.
• You should report excessive bleeding or bleeding that continues for a prolonged period to your doctor.

Test Results

Although normal results may vary, high levels of bilirubin could indicate that your liver is not working properly. An abnormal result doesn’t necessarily mean that you have a medical condition. Some medications, foods, and strenuous exercise can cause higher bilirubin levels than usual. Talk to your provider to find out what your results mean.

Normal values for direct bilirubin in an older adult or child are 0 to 0.4 milligrams per deciliter (mg/dL). The normal values for total bilirubin range from 0.3 to 1.0 mg/dL.

The indirect bilirubin is the sum of the total bilirubin and the direct bilirubin. Normal reference ranges can vary from one lab to the next.

Higher bilirubin levels in newborns are due to stress from birth. Indirect bilirubin should be below 5.2 mg/dL within 24 hours after birth. Many newborns develop jaundice or bilirubin levels above 5 mg/dL within the first few hours after birth.

Interpreting Results

If you have high levels of bilirubin in your blood, your doctor may request additional blood tests or an ultrasound. High levels of bilirubin in adults could be caused by problems with the liver, gallbladder, or bile ducts. Examples include:

• Liver diseases such as Hepatitis
• Gilbert’s Syndrome, a rare genetic condition
• Cirrhosis is scarring of your liver
• Gallstones
• Cancer of either the gallbladder or pancreas
• Biliary stricture is a condition where bile ducts are too narrow for fluid to flow.
• Drug toxicity

Problems in the blood, rather than problems in your liver, could also cause high bilirubin. The following can lead to blood cells falling apart too quickly:

• Hemolytic Anemia is when too many blood cells are being destroyed by an autoimmune disease or genetic defect. The liver cannot metabolize the indirect bilirubin present in the body.
• Transfusion reaction – This happens when your immune system attacks the blood you have received through a transfusion.

Infant Jaundice

High (often indirect) bilirubin or jaundice in infants can be dangerous. This could be due to many factors. There are three types of jaundice:

• Psychological Jaundice. A temporary delay in the functioning of the liver. Usually not severe.
• Breastfeeding Jaundice is a condition that occurs in the first week of a baby’s life. It can be caused by low or no milk supply from the mother.
• Breast Milk Jaundice occurs after approximately two to three weeks of age, and is caused by some substances in breastmilk.

These conditions can all be treated easily and are generally harmless. High bilirubin or jaundice in infants can be caused by:

• An abnormal shape of blood cells, such as sickle cell anemia.
• A mismatch in blood type between mother and infant can lead to severe hemorrhage. This is called erythroblastosis fetus.
• Genetic defects can cause the deficiency of some important proteins
• High levels of red blood cell count due to the small size
• Due to difficult delivery, bruising
• Infections

What To Do in Case of High Levels?

Your doctor may order additional tests to rule out the cause if your blood tests reveal abnormally high levels.

After your doctor has diagnosed the cause of high levels of bilirubin, you may need to have additional bilirubin blood testing to ensure that your treatment is effective.

Your doctor may order imaging tests to confirm that your liver and gallbladder are functioning normally.

Also Read: Top 9 Annual Blood Tests to Keep You Healthy and Active

Final Takeaway

The bilirubin test is not the only way to determine your liver health. You may require additional tests if your provider suspects that you have liver disease or a disorder of the red blood cells. These tests could include:

• A liver function test is a set of tests that measures different substances in your blood.
• Liver protein tests
• Urine tests
• An ultrasound
• To obtain a sample from your liver to be examined under a microscope, you will need to do a liver biopsy

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  https://medlineplus.gov/lab-tests/bilirubin-blood-test/

• Bilirubin. (2017).
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• Bilirubin, total and direct, neonatal. (n.d.).
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• Mayo Clinic Staff. (2014). Infant jaundice.
  mayoclinic.org/diseases-conditions/infant-jaundice/symptoms-causes/syc-20373865
• Mayo Clinic Staff. (2018). Bilirubin test.
  mayoclinic.org/tests-procedures/bilirubin/about/pac-20393041
• Preud’Homme DL. (2012). Neonatal jaundice.
  patients.gi.org/topics/neonatal-jaundice/

Reference intervals – MGH Clinical Laboratories. (2011).
mghlabtest.partners.org/MGH_Reference_Intervals_August_2011.pdf