Sign in →

Test Code ARSAB Arylsulfatase A, Blood Spot


Ordering Guidance


This test primarily serves as a second-tier assay to be used by newborn screening programs to screen for metachromatic leukodystrophy when first tier sulfatide analysis is abnormal. The test can also be used to screen patients at risk for metachromatic leukodystrophy.



Specimen Required


Supplies: Card-Blood Spot Collection (Filter Paper) (T493)

Container/Tube:

Preferred: Card-Blood Spot Collection (Filter Paper)

Acceptable: PerkinElmer 226 filter paper, Munktell filter paper, Whatman protein Saver 903 paper, local newborn screening card, or blood collected in tubes containing EDTA (preferred) or heparin and dried on filter paper

Specimen Volume: 2 Blood spots

Collection Instructions:

1. Completely fill at least 2 circles on the filter paper card (approximately 100 microliters blood per circle).

2. Let blood dry on filter paper at ambient temperature in a horizontal position for a minimum of 3 hours.

3. Do not expose specimen to heat or direct sunlight.

4. Do not stack wet specimens.

5. Keep specimen dry and freeze (with desiccant if necessary).

Additional Information:

1. For collection instructions, see Blood Spot Collection Instructions

2. For collection instructions in Spanish, see Blood Spot Collection Card-Spanish Instructions (T777)

3. For collection instructions in Chinese, see Blood Spot Collection Card-Chinese Instructions (T800)


Useful For

Second-tier newborn screening test for metachromatic leukodystrophy (MLD) when sulfatides are elevated

 

Enzymatic test for detection of arylsulfatase A deficiency

 

This test is not suitable for carrier detection.

Method Name

Flow Injection Analysis Tandem Mass Spectrometry (MS/MS)

Reporting Name

Arylsulfatase A, BS

Specimen Type

Whole blood

Specimen Minimum Volume

1 Blood spot

Specimen Stability Information

Specimen Type Temperature Time Special Container
Whole blood Frozen (preferred) 28 days FILTER PAPER
  Refrigerated  14 days FILTER PAPER

Reject Due To

Blood spot specimen that shows serum rings or has multiple layers Reject
Nonapproved filter paper Reject

Reference Values

Normal: ≥0.100 mmol/mL/hr

Day(s) Performed

Monday, Thursday

Report Available

3 to 6 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information

82657

LOINC Code Information

Test ID Test Order Name Order LOINC Value
ARSAB Arylsulfatase A, BS 55912-0

 

Result ID Test Result Name Result LOINC Value
623015 Interpretation 59462-2
623013 Arylsulfatase A 55912-0
623014 Reviewed By 18771-6