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Calcium Bilirubinate, Stone — Mass Fraction

Published: August 9, 2026Updated: August 16, 2026

A laboratory analysis that measures the proportion of calcium bilirubinate in a removed stone, such as a gallstone, to identify the stone's composition.

Quick summary

["This test identifies how much of a stone is made of calcium bilirubinate."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
54439-5
Short code
Ca Bilirub MFr Stone
Synonyms
Ca Bilirub MFr Stone
Category
liver
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

What is this test?

This test measures the mass fraction, or proportion, of calcium bilirubinate in a stone that has been removed for laboratory analysis. Calcium bilirubinate is a pigment that can be a major component of pigment-type gallstones.

Why might I need this test?

You may need this test if a gallstone or another removed stone is being analyzed. Knowing the stone's composition can help your clinician estimate the risk of another stone and discuss ways to reduce the chance of recurrence.

How is the test performed?

A laboratory receives the removed stone and analyzes a measured portion to determine the proportion made of calcium bilirubinate. The result is reported as a mass fraction rather than as a simple positive or negative finding.

How do I prepare for the test?

This test is usually performed on a stone collected during a procedure, so special preparation such as fasting is not required. If you have a stone to submit, follow your clinician's collection, storage, and transport instructions.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Calcium Bilirubinate in Stone

Frequently asked questions

Does this test measure bilirubin in my blood?
No. It measures the amount of calcium bilirubinate within a removed stone. Blood bilirubin tests are separate tests.
What does a high result mean?
A high result indicates that a larger proportion of the stone is composed of calcium bilirubinate. Your clinician can explain how this relates to the type of stone and your risk of future stones.
Will the result tell me why the stone formed?
Not by itself. The result identifies the stone's composition, but the cause of stone formation may also depend on medical history, imaging, and other laboratory tests.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy