AD-Detect™ ABeta 42/40 and p-tau217 Evaluation, Plasma

Test Code

14258

CPT Code(s)

82233, 82234, 84393

Test Code

14258

CPT Code(s)

82233, 82234, 84393

Not offered in Quest Diagnostics Nichols Institute (IFD) – San Juan Capistrano. Please provide SERVICE AREA INFORMATION to find available tests you can order.

In-home collection is not available in your area through Quest Mobile.

Clinical Significance

AD-Detect™ ABeta 42/40 and p-tau217 Evaluation, Plasma - Intended use is for Alzheimer's Diagnosis. Independent measurement and interpretation of plasma amyloid ratios (AB42/40) and phosphorylated tau levels (p-tau181 and p-tau217) provide clinically valuable insight into patient risk for development of Alzheimer's disease. However, by combining core AD pathological markers for a single analytical interpretation have been shown to significantly improve predictive performance and accuracy for detecting amyloid positivity and confirming a diagnosis of Alzheimer's disease. The AD-Detect™ ABeta 42/40 and p-tau217 Evaluation, Plasma evaluates a patient's ...

Test Resources

Test FAQ

Quest Dementia Testing

Clinical Focus

Dementia: Biomarkers for Differential Diagnosis and Alzheimer's Disease Assessment

Test Details

Includes

AD-Detect™ Likelihood Score Interpretation
Quest AD-Detect™ Beta-Amyloid 42/40 Ratio, Plasma
Quest AD-Detect™ Phosphorylated tau217(p-tau217), Plasma
AD-Detect™ Likelihood Score

Patient Preparation

Patients should be cautioned to stop biotin consumption at least 72 hours prior to collection of a sample

Methodology

Immunoassay (IA) • Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)

Assay Category

This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Reference Range(s)

ABeta 42	Not Established
ABeta 40	Not Established
ABeta 42/40 Ratio	≥0.170
AD Detect p-tau217	≤0.15 pg/mL

AD Detect Likelihood Score
Likelihood of amyloid PET positivity
Low Likelihood	<0.3254
Indeterminant	0.3254-0.6460
High Likelihood	>0.6460

Alternative Name(s)

Phosphorylated tau,ptau 217,AB 42,Dementia,Alzheimer's Diagnostic panel,Alzheimer’s Disease,Alzheimer's diagnosis,Amyloid beta 42,Phospho tau

LOINC® Codes, Performing Laboratory

Service Area must be determined

Includes

AD-Detect™ Likelihood Score Interpretation
Quest AD-Detect™ Beta-Amyloid 42/40 Ratio, Plasma
Quest AD-Detect™ Phosphorylated tau217(p-tau217), Plasma
AD-Detect™ Likelihood Score

Patient Preparation

Patients should be cautioned to stop biotin consumption at least 72 hours prior to collection of a sample

Methodology

Immunoassay (IA) • Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)

Assay Category

Reference Range(s)

ABeta 42	Not Established
ABeta 40	Not Established
ABeta 42/40 Ratio	≥0.170
AD Detect p-tau217	≤0.15 pg/mL

AD Detect Likelihood Score
Likelihood of amyloid PET positivity
Low Likelihood	<0.3254
Indeterminant	0.3254-0.6460
High Likelihood	>0.6460

Alternative Name(s)

Phosphorylated tau,ptau 217,AB 42,Dementia,Alzheimer's Diagnostic panel,Alzheimer’s Disease,Alzheimer's diagnosis,Amyloid beta 42,Phospho tau

LOINC® Codes, Performing Laboratory

Service Area must be determined

Preferred Specimen(s)

2.5 mL total plasma collected in a K2 EDTA (lavender-top) tube split into two equal aliquots

Minimum Volume

1.2 mL

Collection Instructions

Quest Diagnostics does not perform this test for individuals under the age of 18. Pre-test and post-test counseling is strongly recommended.

Collect blood into a K2 EDTA (lavender-top) tube and mix by inversion 10 times. Centrifuge to separate plasma from cells within 1 hour of collection. Carefully transfer plasma into 2 separate polypropylene tubes or 2 separate Quest issued polypropylene pour-off/transfer tubes. Do not transfer to conical tubes. Store frozen.

Transport Container

Transport tube(s)

Transport Temperature

Frozen

Specimen Stability

Room temperature: Unacceptable
Refrigerated: 72 hours
Frozen: 28 days

Reject Criteria

Moderate or gross hemolysis • Specimen collected in a glass, polystyrene, or polycarbonate tube • K3 EDTA tube • K2 EDTA gel separator tube

Setup Schedule

Service Area must be determined

Preferred Specimen(s)

2.5 mL total plasma collected in a K2 EDTA (lavender-top) tube split into two equal aliquots

Minimum Volume

1.2 mL

Collection Instructions

Transport Container

Transport tube(s)

Transport Temperature

Frozen

Specimen Stability

Room temperature: Unacceptable
Refrigerated: 72 hours
Frozen: 28 days

Reject Criteria

Moderate or gross hemolysis • Specimen collected in a glass, polystyrene, or polycarbonate tube • K3 EDTA tube • K2 EDTA gel separator tube

Setup Schedule

Service Area must be determined

Not offered in Quest Diagnostics Nichols Institute (IFD) – San Juan Capistrano. Please provide SERVICE AREA INFORMATION to find available tests you can order.

In-home collection is not available in your area through Quest Mobile.

Test Details

Clinical Significance

Test Resources

Reference ranges are provided as general guidance only. To interpret test results use the reference range in the laboratory report.

The CPT codes provided are based on AMA guidance and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

This material contains content from LOINC® (http://loinc.org). The LOINC Table, LOINC Table Core are copyright © 1995-2019, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and is available at no cost under the license at http://loinc.org/license.

The tests listed by specialty and category are a select group of tests offered. For a complete list of Quest Diagnostics tests, please adjust the filter options chosen, or refer to our Directory of Services.