Bilirubin is formed by the breakdown of haemoglobin (unconjugated/indirect bilirubin) and converted to water-soluble form by hepatocytes, (conjugated or direct bilirubin.) It is then secreted into bile and passed into the gut. Most are reabsorbed by the liver, whilst the remainder is converted to urobilinogen, and either reabsorbed by the kidneys or excreted by the faeces after conversion to stercobilin. Jaundice is yellow discolouration to the skin or sclera due to hyperbilirubinaemia. Elevated levels of bilirubin may indicate an obstruction of bile flow or a problem in the processing of bile by the liver.
Bilirubin is produced as a by-product of haemoglobin metabolism and testing for Bilirubin is usually one of a group of tests used to investigate the health of the liver.
There are 3 main causes of jaundice : pre-hepatic (raised indirect unconjugated bilirubin), inter-hepatic (mixed picture of raised direct and indirect bilirubin) and post-hepatic (raised conjugated hyperbilirubinaemia).
The most common cause of an isolated high bilirubin level is Gilberts syndrome and haemolysis.
Pre-hepatic raised unconjugated/indirect bilirubin
- Haemolysis – check FBC also
- Gilbert’s syndrome
- Haematoma reabsorption
- Post viral hepatitis
- Mild chronic hepatitis
- Crigler-Najjar syndrome
Interhepatic causes of conjugated/direct hyperbilirubinaemia
- Hepatocellular disease
- Viral infections (hepatitis ABC, EBV, CMV)
- Chronic alcohol use
- Autoimmune disorders
- Drug toxicity
- Parental nutrition
- Inherited defects of excretion
- Dublin Johnson Syndrome
- Rotors Syndrome
- Primary biliary cirrhosis
- Primary sclerosing cholangitis
- Hepatocellular carcinoma
Post-hepatic causes of conjugated direct hyperbilirubinaemia
- Intra-luminal causes : gallstones, cholestasis from blocked common bile duct, Infection
- Mural causes : intrahepatic malignancy, cholangiocarcinoma, surgical strictures or drug-induced cholestasis
- Extra-mural causes: pancreatic cancer, lymphomas, pancreatitis
Delivering True Innovation
5mL venous serum or plasma
Enfer Medical offers colorimetric technology for the quantitative assay for Total Bilirubin. This test is CE-IVD certified.
For clients using the Enfer Medical Client Portal, the Enfer Medical Patient Request Form (PRF) will be generated when you have completed your “Test Request” within the portal linked below.
Please note that samples suspected of containing high risk pathogens such as Mycobacterium tuberculosis should be clearly identified on the form and packed separately from other samples.
Results are available next working day.
This assay is available seven days a week.
The packaging/preparation of samples for delivery to the laboratory are required to be in adherence to all national regulations for the safe transport of biological materials. HSE guidance can be reviewed HERE.
There are specific packaging instructions and labelling requirements requiring triple packaging including:
- Primary leak-proof container – tube or vial containing the sample.
- Secondary watertight container, with absorbent material, intended to protect the primary container.
- Outer container protects the secondary container.
- Patient Request forms must be placed between the secondary container and the outer shipping container.
Further information on the packaging/preparation of samples for delivery to the laboratory is contained within the Enfer Medical Laboratory User Manual which clients are provided with.
Storage & Stability
Specimens must be tested within 1 day of collection and stored at 2-8°C.
In addition to the packaging of samples, the transport/delivery of clinical samples to the laboratory is required to be in adherence to all national regulations for the safe transport of biological materials. Enfer Medical provides a fully compliant logistics service, aligned with clients’ testing requirements.
Prompt transport of specimens:
To ensure prompt testing of samples and release of results within the published test turnaround times, samples should arrive to the laboratory by 18:00. Test turnaround time is measured from receipt of the sample at the laboratory until the time the authorised results are reported to users.
In rare cases specimens may not be suitable for testing on arrival to the laboratory. In that case the sample will be rejected at the receipt stage and the service user will be notified immediately and an explanation as to why the sample could not be processed will be provided. Reasons why samples cannot be processed include but are not limited to:
- Samples received beyond the stability limits and/or not at the correct temperature indicated for each test.
- Incorrect sample type received.
- Leaking samples, sample not received or sample insufficient for analysis as stated below within sample requirements.
- Non-compliant samples or request forms i.e. those missing sample date information, missing sample test request and/or missing sample site/type information.
- Samples received without the necessary patient identifiers.
Quantitative results for Bilirubin Total are reported in numeric value in µmol/L. Please contact us for more information on the reference ranges used at Enfer Medical.
Following receipt at the Laboratory, results should be available on the next working day and will be reported to the referring clinician via the Enfer Medical Client Portal or in a format agreed with clients.
Established clients can login to the portal using the link above.