Quest AD-Detect® Phosphorylated tau181(p-tau181), Plasma

Test Code

13690

CPT Code(s)

84393

Test Code

13690

CPT Code(s)

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 may be available in your area for purchase through Quest Mobile.

Clinical Significance

Quest AD-Detect® Phosphorylated tau181(p-tau181), Plasma - Intended to be used as an aid in the initial assessment for Alzheimer's disease and other causes of cognitive decline in adult patients aged 55 years and older, presenting with signs, symptoms, or complaints of cognitive decline. The result should be interpreted in conjunction with other clinical information. A negative test result is consistent with a negative amyloid positron emission tomography (PET) scan result and reduced likelihood that a patient's cognitive impairment is due to amyloid pathology. These patients should be investigated for other causes of cognitive decline.

A positive ...

Test Resources

Test FAQ

Quest Dementia Testing

Clinical Focus

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

Test Details

Patient Preparation

Dietary supplements containing biotin may interfere in assays and may skew results to be either falsely high or falsely low. For patients receiving the recommended daily doses of biotin, draw samples at least 8 hours following the last biotin supplementation. For patients on mega-doses of biotin supplements, draw samples at least 72 hours following the last biotin supplementation.

Methodology

Electrochemiluminescence (ECLIA)

Reference Range(s)

≤0.72 pg/mL

Alternative Name(s)

181,Ptau,PhosphoTau-181P,P tau,ptau 181

LOINC® Codes, Performing Laboratory

Service Area must be determined

Patient Preparation

Methodology

Electrochemiluminescence (ECLIA)

Reference Range(s)

≤0.72 pg/mL

Alternative Name(s)

181,Ptau,PhosphoTau-181P,P tau,ptau 181

LOINC® Codes, Performing Laboratory

Service Area must be determined

Preferred Specimen(s)

1 mL plasma collected in an EDTA (lavender-top) tube

Minimum Volume

0.5 mL

Transport Container

Transport tube

Transport Temperature

Room temperature

Specimen Stability

Room temperature: 14 days
Refrigerated: 22 days
Frozen: 22 days

Reject Criteria

Hemolysis

Setup Schedule

Service Area must be determined

Preferred Specimen(s)

1 mL plasma collected in an EDTA (lavender-top) tube

Minimum Volume

0.5 mL

Transport Container

Transport tube

Transport Temperature

Room temperature

Specimen Stability

Room temperature: 14 days
Refrigerated: 22 days
Frozen: 22 days

Reject Criteria

Hemolysis

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 may be available in your area for purchase 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.

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