Test Code AGA Alpha-Galactosidase, Leukocytes
Performing LaboratoryMayo Medical Laboratories in Rochester
Diagnosis of Fabry disease in males
Verifying abnormal serum alpha-galactosidase results in males with a clinical presentation suggestive of Fabry disease
The following algorithms are available in Special Instructions:
-Fabry Disease: Newborn Screen-Positive Follow-up
-Fabry Disease Testing Algorithm
Reporting NameAlpha-Galactosidase, Leukocytes
Specimen TypeWhole Blood ACD
Specimen must arrive within 72 hours of draw to be stabilized. Specimen received after 72 hours could have falsely normal results. Draw specimen Monday through Thursday only and not the day before a holiday. Specimen should be drawn and packaged as close to shipping time as possible.
Preferred: Yellow top (ACD solution B)
Acceptable: Yellow top (ACD solution A)
Specimen Volume: 6 mL
Collection Instructions: Do not transfer blood to other containers.
1. New York Clients-Informed consent is required. Please document on the request form or electronic order that a copy is on file. An Informed Consent for Genetic Testing (T576) is available in Special Instructions.
2. If not ordering electronically, complete, print, and send a Neurology Test Request Form-General (T732) with the specimen (http://www.mayomedicallaboratories.com/it-mmfiles/neurology-request-form.pdf)
3. Biochemical Genetics Patient Information (T602) in Special Instructions.
Specimen Minimum Volume
Specimen Stability Information
|Whole Blood ACD||Refrigerated (preferred)||72 hours|
Reject Due To
Mild OK; Gross reject
≥23.1 nmol/hour/mg protein
An interpretative report will be provided.
Note: Results from this assay do not reflect carrier status because of individual variation of alpha-galactosidase enzyme levels.
Deficiency of alpha-galactosidase A (alpha-Gal A) is diagnostic for Fabry disease in males.
Urine sediment analysis (CTSA / Ceramide Trihexosides and Sulfatides, Urine) for the accumulating trihexoside substrate is also recommended.
Carrier females usually have alpha-galactosidase levels in the normal range; therefore, molecular sequence analysis of the GLA gene (FABRZ / Fabry Disease, Full Gene Analysis) is recommended as the appropriate diagnostic test for females.
Day(s) and Time(s) Performed
Specimens are processed Monday through Sunday.
Assay is performed on Tuesday.
Analytic Time8 days
Specimen Retention TimeWBC homogenate stored 1 month
Test ClassificationThis test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.
CPT Code Information
LOINC Code Information
|Test ID||Test Order Name||Order LOINC Value|
|AGA||Alpha-Galactosidase, Leukocytes||In Process|
|Result ID||Test Result Name||Result LOINC Value|
|32302||Reason for Referral||42349-1|