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Test ID AD2AR PrecivityAD2, Reflex to Apolipoprotein E, Plasma


Ordering Guidance


This blood test is intended for use in patients aged 55 and older with signs or symptoms of mild cognitive impairment or dementia who are undergoing evaluation for Alzheimer disease or other forms of cognitive decline, and who have not had prior apolipoprotein E proteotyping or APOE genotyping.



Shipping Instructions


1. Specimens must be shipped frozen on dry ice.

2. Place labeled aliquot tubes inside a larger tube or vial for transport.



Specimen Required


Supplies: Screw cap micro tube, 2 mL, PCR Performance Tested, Low protein-binding (T983)

Collection Container/Tube: 10 mL Purple top (K EDTA)

Submission Container/Tube: Two 2-mL screw cap micro tubes

Specimen Volume: 3 mL in 2 tubes, each containing 1.5 mL

Collection Instructions:

1. Centrifuge within two hours of collection.

2. Label two 2-mL screw-cap micro tubes.

3. Aliquot 1.5 mL of plasma into each labeled micro tube.

4. Freeze plasma (no longer than 2 hours after collection) at or below -20° C.


Useful For

Assisting in the evaluation of adult patients, aged 55 years and older, with signs or symptoms of mild cognitive impairment or dementia who are being assessed for Alzheimer disease and other causes of cognitive decline

 

Determining APOE E4 status to aid in medical management and treatment decisions when the PrecivityAD2 blood test result is positive

 

This test is not intended for patients younger than 55 years, or for use as a screening test in patients without signs or symptoms of cognitive, or for serial testing for assessment of longitudinal changes.

Reflex Tests

Test ID Reporting Name Available Separately Always Performed
C2NAP Precivity-ApoE No No

Testing Algorithm

When this test result is positive, then apolipoprotein E testing will be performed at an additional charge.

Method Name

Immunoprecipitation/Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)

Reporting Name

PrecivityAD2 Reflex to ApoE

Specimen Type

Plasma

Specimen Minimum Volume

See Specimen Required

Specimen Stability Information

Specimen Type Temperature Time Special Container
Plasma Frozen

Reference Values

Amyloid Probability Score 2 (APS2) (range of 0-100):

Negative: 0-47

Positive: 48-100

 

Abeta42/40 Ratio:

≥0.095 Consistent with absence of amyloid plaques

 

Percent p-tau217:

<4.2% consistent with absence of brain amyloid plaques

 

ApoE Proteotype

E2/E2, E2/E3, E2/E4, E3/E3, E3/E4, E4/E4

-E3 is the most common allele.

-E4 allele is associated with increased risk of amyloid plaques.

-E2 allele is associated with lower risk of amyloid plaques.

Day(s) Performed

Monday through Friday

Report Available

15 days post sample receipt from MCL

Performing Laboratory

C2N Diagnostics LLC

Test Classification

C2N Diagnostics has developed and determined the analytical and clinical validity performance characteristics of this Laboratory Developed Test (LDT). This assay has been validated pursuant to CLIA regulations and is used for clinical purposes. This assay has not been cleared or approved by the FDA.

CPT Code Information

81599

LOINC Code Information

Test ID Test Order Name Order LOINC Value
AD2AR PrecivityAD2 Reflex to ApoE Not Provided

 

Result ID Test Result Name Result LOINC Value
C2RG Amyloid Probability Score 2 (APS2) Not Provided
C2RGF APS2 Result Not Provided
C2RH APS2 Result Interpretation Not Provided
C2RI APS2 Result Reference Interval Not Provided
C2RJ APS2 Description Not Provided
C2RK Percent p-tau217 Not Provided
C2RL Percent p-tau217 Reference Interval Not Provided
C2RLD Percent p-tau217 Description Not Provided
C2RM Abeta42/40 Ratio Not Provided
C2RN Abeta42/40 Ratio Reference Interval Not Provided
C2RND Abeta42/40 Ratio Description Not Provided
C2RO Test Description Not Provided
C2RP Limitations of Test Result Not Provided
C2RQ Methods and Assay Category Not Provided
C2RR References Not Provided
C2RRC Report Comment Not Provided
C2RRF Performing Site Not Provided