Sign in →

Test Code LAB8661 Alpha-Galactosidase, Leukocytes

Additional Codes

AGAW


Ordering Guidance


If testing is needed for assessment of meat or meat-derived product allergy, order either ALGAL / Galactose-Alpha-1,3-Galactose (Alpha-Gal), IgE, Serum or APGAL / Galactose-Alpha-1,3-Galactose (Alpha-Gal) Mammalian Meat Allergy Profile, Serum.

 

Carrier detection using enzyme levels is unreliable for female patients as results may be within the normal values. Order FABRZ / Fabry Disease, Full Gene Analysis, Varies for testing carrier status.



Shipping Instructions


For optimal isolation of leukocytes, it is recommended the specimen arrive refrigerated within 6 days of collection to be stabilized. Collect specimen Monday through Thursday only and not the day before a holiday. Specimen should be collected and packaged as close to shipping time as possible.



Specimen Required


Container/Tube:

Preferred: Yellow top (ACD solution B)

Acceptable: Yellow top (ACD solution A) or lavender top (EDTA)

Specimen Volume: 6 mL

Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.


Forms

1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available:

-Informed Consent for Genetic Testing (T576)

-Informed Consent for Genetic Testing-Spanish (T826)

2. Biochemical Genetics Patient Information (T602)

3. If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.

Secondary ID

606261

Useful For

Diagnosis of Fabry disease in male patients

 

Verifying abnormal serum alpha-galactosidase results in male patients with a clinical presentation suggestive of Fabry disease

 

This test is not useful for patients undergoing a work-up for a meat or meat-derived product allergy.

Testing Algorithm

Additional information is available:

-Fabry Disease: Newborn Screen-Positive Follow-up

-Fabry Disease Diagnostic Testing Algorithm

 

If the patient has abnormal newborn screening results for Fabry disease. Refer to the appropriate ACMG Newborn Screening ACT Sheet.(1)

Method Name

Flow Injection Analysis-Tandem Mass Spectrometry

Specimen Type

Whole Blood ACD

Specimen Minimum Volume

2 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Whole Blood ACD Refrigerated (preferred) 6 days
  Ambient  6 days
Medical University of South Carolina Note:

On-campus collections: Tube to 99 or deliver to University Extension Hospital Room EH318 
Send ACD Whole Blood, Refrigerated
 
Off-campus collections: Do NOT Spin! Specimen to be stored/transported at Refrigerated temp. 
 

Reject Due To

Gross hemolysis Reject

Reference Values

≥10.32 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.

Interpretation

Values below the reference range are consistent with a diagnosis Fabry Disease.

 

When abnormal results are detected, a detailed interpretation is given, including an overview of the results and of their significance, a correlation to available clinical information, elements of differential diagnosis, recommendations for additional biochemical testing and in vitro, confirmatory studies (enzyme assay, molecular analysis), name and phone number of key contacts who may provide these studies, and a phone number to reach one of the laboratory directors in case the referring physician has additional questions.

Method Description

The specimens are incubated with a mix of substrate and internal standard for acid sphingomyelinase, beta-glucocerebrosidase, acid alpha-glucosidase, alpha-galactosidase, galactocerebrosidase  and alpha-L-iduronidase. The sample is then purified by liquid-liquid extraction. The extract is evaporated and reconstituted before analysis by tandem mass spectrometry.(Unpublished Mayo method)

Day(s) Performed

Preanalytical processing: Monday through Saturday

Assay performed: Monday, Wednesday

Report Available

5 to 7 days

Specimen Retention Time

WBC homogenate: 1 month

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

82657

LOINC Code Information

Test ID Test Order Name Order LOINC Value
AGAW Alpha-Galactosidase, Leukocytes 24049-9

 

Result ID Test Result Name Result LOINC Value
606261 Alpha-Galactosidase, Leukocytes 24049-9
606262 Interpretation 59462-2
606263 Reviewed By 18771-6