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Alpha-N-acetylgalactosaminidase, Serum/Plasma — Catalytic Concentration

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

Measures the activity of alpha-N-acetylgalactosaminidase, a lysosomal enzyme, in blood. It is most often used in the evaluation of a suspected inherited enzyme deficiency.

Quick summary

["This test measures blood levels of alpha-N-acetylgalactosaminidase enzyme activity."]

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

Key facts at a glance

LOINC
1837-4
Short code
A-NAG SerPl-cCnc
Synonyms
A-NAG SerPl-cCnc
Category
liver
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
86038
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?

Alpha-N-acetylgalactosaminidase, also called ANAG, is an enzyme that helps break down certain complex sugars inside cells. This test measures ANAG enzyme activity in serum or plasma.

Why might I need this test?

This uncommon test may be ordered when symptoms suggest a lysosomal storage disorder, particularly alpha-N-acetylgalactosaminidase deficiency, also known as Schindler disease. It is usually interpreted by a specialist along with other laboratory and clinical findings.

How is the test performed?

A blood sample is collected, and the laboratory measures the activity of the ANAG enzyme. Depending on the test method, the result may reflect enzyme activity per unit volume of blood.

How do I prepare for the test?

No special preparation is usually required for this test. Follow the laboratory's instructions and tell the care team about any medicines, recent transfusions, or other tests that may affect the results.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Reduced alpha-N-acetylgalactosaminidase activity may indicate an inherited deficiency of the enzyme, which can be associated with a lysosomal storage disorder. Results should be interpreted with symptoms, family history, and other laboratory tests because low activity does not establish a diagnosis by itself.

Short name

Alpha-N-acetylgalactosaminidase activity

Frequently asked questions

What does alpha-N-acetylgalactosaminidase do?
This enzyme helps break down certain complex sugars within lysosomes, which are structures that recycle cellular material. Proper enzyme activity is important for normal cell function.
What does a low result mean?
A low result can occur with an inherited alpha-N-acetylgalactosaminidase deficiency. A doctor or genetic specialist should interpret the result with the rest of the medical evaluation.
Is this a routine blood test?
No. It is a specialized test usually ordered when a particular inherited metabolic or lysosomal disorder is being evaluated.
  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