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

Test Code

13690

Alias/See Also

LAB01222

CPT Codes
83520

Preferred Specimen

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

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.

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 (Eg, hemolysis? Lipemia? Thaw/Other?)

Hemolysis

Methodology
Electrochemiluminescence (ECLIA)

FDA Status
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.

Setup Schedule

Mon-sat

Report Available

2-5 days

Reference Range

<55 years	≤0.86 pg/mL
≥55 years	≤1.07 pg/mL

Clinical Significance

p-tau181 is a diagnostic biomarker for Alzheimer's Disease (AD) that is useful in identifying patients with underlying AD tau pathology. It can predict the cognitive decline in AD/MCI patients and correlates with amyloid and tau PET results.

Performing Laboratory

Quest Diagnostics Nichols Institute-San Juan Capistrano, CA

33608 Ortega Highway

San Juan Capistrano, CA 92675-2042

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.