Bile Acid Test

Bile acids are formed in the liver. They are crucial for the digestion and absorption of lipids, nutrients and fats into the intestine. Waste products, including bilirubin, are removed from the body by secretion into bile and faeces.

The bile test is used to diagnose jaundice, gallbladder disease and hepatobiliary diseases such as acute hepatitis or liver cancer, etc. It analyzes your liver by measuring the bilirubin value in your blood or urine. Excess of bilirubin, obstruction or inflammation of the liver may be the cause of liver problems. In the case of a high bilirubin range, you may suffer from jaundice or other liver-related diseases.

The bile acid test shows the bilirubin level in your blood or urine. The bile test results are usually expressed as mg/dL (milligrams of bilirubin per deciliter of blood). The high or low bilirubin levels don't indicate any specific disease but help in diagnosing the causes of liver non-functioning and blood problems etc.

In fact, higher bilirubin levels could cause severe diseases. That's why when a person suffers from any problem in the liver functioning and shows symptoms like dark urine, yellowing of skin and eyes, abdominal pain or swelling, light-coloured stools etc., he or she is advised to take the test.

In blood, bilirubin exists in two forms. A total bilirubin blood test includes unconjugated (indirect) and conjugated (direct) bilirubin. Initially, bilirubin is unconjugated, which means that bilirubin remains attached to albumin (protein in blood that carries vitamins, enzymes and other crucial substances to your liver). It becomes conjugated after undergoing the process of conjugation in the liver with glucuronide. This is water-soluble and excreted into the bile.

Delta bilirubin is formed when the excretion of conjugated bilirubin by the liver is impaired due to bile duct obstruction, etc. Neonatal bilirubin is common in newborns, in which total bilirubin increases, specifically due to the increase in unconjugated bilirubin. However, its level reaches normal one week after the baby's birth. Still, higher bilirubin causes fatal damage to infants and that's why newborns are often tested shortly after their birth.

The urinary bilirubin test measures levels of bilirubin in your urine.

Other names of bile acid test

• Bilirubin test
• Bilirubin blood test
• Urinary bilirubin test
• Comprehensive bilirubin blood test
• Bile acids serum test

What does the bile test detect or measure and who is this prescribed for?

The test is prescribed to measure blood and urine bilirubin levels. Through the test, the healthcare experts diagnose the cause of liver-related diseases, jaundice, liver cancer, pancreas damage, hepatobiliary diseases, Ampullary carcinoma etc.

The bilirubin blood tests measure the bilirubin present in your blood and the urinary bilirubin test checks the presence of bilirubin in your urine.

Your doctor may suggest you get tested if you notice the below-mentioned symptoms:

• Dark urine
• Nausea
• Abdominal pain/swelling
• Clay-coloured stools
• Jaundice (yellowing of eyes and skin)
• Anaemia or low red blood cells
• Drug toxicity
• Flu-like symptoms, such as fever and chills

These symptoms aren't inclusive and may include other related symptoms connected to bilirubin abnormality or imbalance in the opinion of healthcare experts.

Bile test reports show reference ranges that are the bilirubin normal range. The bilirubin range above the reference range may be an indication of disease.

The reference ranges for the bile acid test may vary depending on the laboratory that analyzes your blood or urine samples. According to The American Board of Internal Medicine, the normal bilirubin reference ranges for adults are mentioned below:

As these ranges aren't universal, you must discuss your bile acid test reports with a specialist doctor or Gastroenterologist.

In a newborn, normal indirect bilirubin is under 5.2 mg/dL within the first 24 hours of birth. However, many newborns have high bilirubin levels above 5 mg/dL.

A urinary bilirubin test result indicates bilirubin positive/negative. Bilirubin positive means the presence of bilirubin in your urine and negative means the absence of bilirubin. A healthy person having a healthy liver doesn't have bilirubin in urine.

Newborns have normally higher bilirubin levels which remain higher for usually 48 hours of birth.

If your urinary bilirubin test is positive, then it indicates the presence of bilirubin in your urine. The presence of bilirubin in your urine sample given for diagnosis may indicate the following health conditions:

• liver disease such as hepatitis
• blockage in the structures that carry bile from your liver
• abnormal liver function or unhealthy liver

Bilirubin in urine tests isn't an indication of a specific disease. So if your results are abnormal, your doctor may order additional blood and urine tests. He may also order a panel test such as a urinalysis, liver panel or comprehensive metabolic panel. These panels include multiple blood and urine tests that measure various enzymes, proteins and substances in the liver to diagnose liver diseases.

High bilirubin may be an indication of blood-related problems or diseases of the liver, bile ducts or gallbladder such as:

• Hepatitis
• Cirrhosis
• Gilbert's syndrome
• Biliary stricture due to which the bile duct becomes narrow to allow fluid to pass
• Gallstones or gallbladder or pancreas cancer
• Drug toxicity

In infants, high bilirubin levels might cause certain serious damage such as:

• Sickle cell anaemia
• Erythroblastosis fetalis
• Deficiency of crucial proteins due to genetic defects
• Prematurity infections

Blood or urine samples are given for the bile tests. The doctors analyse the bile test results and may order other tests for further analysis.

Test Preparation

A bilirubin blood test procedure requires a sample of blood usually taken from the vein of your arm. A urinary bilirubin test needs a urine sample.

For the bilirubin blood test, you are required not to eat or drink anything except water 4 hours before the test. For the urinary bilirubin test, your doctor will advise you regarding eating and fasting conditions.

However, you might be asked to stop taking medicines a few days before the bilirubin tests as there are many drugs that can influence its levels, such as penicillin G, sedatives like phenobarbital, diuretics like furosemide (Lasix) and asthma medications like theophylline. Also, avoid taking caffeine and nonsteroidal anti-inflammatory drugs (NSAIDs) called salicylates, such as aspirin and barbiturates, as they can temporarily lower the bilirubin.

So before the tests, talk to your doctor to see if you should stop or continue taking medication. The other instructions regarding the tests might also be given by your doctor for measuring accurate levels of bilirubin.

Test inclusions: what parameters are included?

The bile test uses one parameter, i.e. measuring the level of bilirubin present in your blood and urine.

A high range of bilirubin may damage your liver, bile ducts, gallbladder, etc. A comprehensive bilirubin blood test measures accurate levels of all three bilirubin in your blood: direct, indirect and total.

The lower level of bilirubin isn't dangerous generally; however, according to certain research, bilirubin works as an antioxidant and protects your tissues. Lower bilirubin levels might expose your body organs to damage and can cause certain fatal conditions such as Coronary artery disease, Ulcerative colitis, Brain lesions, eye diseases, strokes, etc.

How frequently should you take this test?

If the bile test report shows higher bilirubin levels in blood or urine, then your doctor may order other tests for determining the causes of the high bilirubin levels.

Once your medication starts, the doctor may ask you to take one or more of the bile tests periodically to monitor the effectiveness of your medication and treatment. If your doctor diagnosed that your liver or gallbladder isn't functioning properly, then you may order imaging tests to ensure there are no structural abnormalities.

Various newborns get jaundice, so they are often tested shortly after birth because a high bilirubin level may affect the brain, lead to deafness and cause intellectual or developmental disabilities.

Jaundice, hepatitis, cirrhosis, gallbladder disease, hemolytic anaemia