Skip to content

Lecithin-Cholesterol Acyltransferase (LCAT) Activity, Serum/Plasma — Normalized

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

LCAT activity measures an enzyme that helps mature HDL and transport cholesterol. Results are usually interpreted alongside a lipid profile and other clinical findings.

Quick summary

["Low LCAT activity may indicate a cholesterol-processing disorder, but results need clinical context."]

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

Key facts at a glance

LOINC
74362-5
Short code
LCAT Act/Nor SerPl
Synonyms
LCAT Act/Nor SerPl
Category
lipid
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 blood test measures the activity of lecithin-cholesterol acyltransferase, an enzyme that helps mature high-density lipoprotein (HDL) and transport cholesterol. The result may be reported relative to a laboratory reference value.

Why might I need this test?

LCAT activity is usually evaluated when cholesterol or HDL levels are unexpectedly abnormal or when a rare inherited disorder affecting cholesterol transport is suspected. It may also be used to monitor certain lipid disorders.

How is the test performed?

A blood sample is drawn from a vein and tested in a laboratory. The laboratory measures the enzyme's activity and may compare it with an expected or reference activity level.

How do I prepare for the test?

Fasting is generally not required unless your clinician requests it as part of a related lipid-panel evaluation. Tell your clinician about any medicines or supplements you take, and follow any specific preparation instructions.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Reduced LCAT activity can occur with inherited LCAT deficiency and may be associated with very low HDL, corneal clouding, anemia, or kidney disease. Activity can also be affected by acquired conditions, including some liver and metabolic disorders, so an abnormal result does not establish a diagnosis by itself.

Short name

LCAT Activity

Frequently asked questions

What does LCAT do?
LCAT is an enzyme that changes the composition of HDL as it transports cholesterol. This process is important for the normal handling of cholesterol in the blood.
Is this the same as an HDL cholesterol test?
No. An HDL cholesterol test measures the amount of cholesterol carried in HDL, while an LCAT activity test measures the function of an enzyme involved in HDL processing. The tests may be ordered together.
What does a low LCAT activity result mean?
Low activity may suggest an inherited cholesterol-transport disorder or another condition that affects lipid metabolism. Your clinician will interpret it with your medical history, other laboratory tests, and any symptoms.
  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