Alpha-Galactosidase A, Dried Blood Spot — Catalytic Concentration
Measures alpha-galactosidase A enzyme activity in a dried blood spot, often used to screen for Fabry disease.
["Low alpha-galactosidase A activity may indicate Fabry disease and should be confirmed with additional testing."]
Key facts at a glance
- LOINC
- 55908-8
- Short code
- A-Galactosidase A DBS-cCnc
- Synonyms
- A-Galactosidase A DBS-cCnc
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 2
- 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 activity of the enzyme alpha-galactosidase A in a dried blood spot. It is commonly used as a screening test for Fabry disease, an inherited condition in which this enzyme activity is reduced.
Why might I need this test?
The test may be ordered when Fabry disease is suspected based on symptoms, family history, or another screening result. It can also be included in screening programs for newborns or high-risk populations.
How is the test performed?
A small blood sample is collected from a finger prick or heel stick and placed on filter paper to form a dried blood spot. The laboratory then measures alpha-galactosidase A enzyme activity in the sample.
How do I prepare for the test?
Fasting is usually not required. Tell the healthcare provider if you recently received a blood transfusion or transfusion of blood products, because these may affect enzyme test results.
Reference range
NCBI: SCC <2.0 ng/mLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Low alpha-galactosidase A activity may be associated with Fabry disease or another condition affecting enzyme activity. Dried blood spot testing is generally considered a screening method, and an abnormal result usually requires confirmation with another specimen or genetic testing. The result should be interpreted by a clinician in the context of symptoms, medical history, and other findings.
Short name
Alpha-galactosidase A activity
Frequently asked questions
What does this blood test check?
Is a low result a diagnosis of Fabry disease?
Does the test require fasting?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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 17, 2026. · Read our editorial policy