Quest AD-Detect® Beta-Amyloid 42/40 Ratio, Plasma
Test code
CPT code(s)*
Test resources
Test FAQ
Details
Includes
ABeta 42
ABeta 40
ABeta 42/40 Ratio
Methodology
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.
Alternative name(s)
ABeta 42,ABeta 40,AB40,AB42,Alzheimer's Disease (AD),AB42/40,AD,ABeta 42/40
Specimen requirements | |
|---|---|
| Patient preparation | None Specified |
| Preferred specimen(s) | 1.2 mL plasma collected in K2 EDTA tube |
| Minimum volume | 0.6 mL |
| Collection instructions | Collect blood into a K2 EDTA Plasma tube and mix by inversion 10 times. Centrifuge to separate plasma from cells within 1 hour of collection. Carefully transfer plasma into a polypropylene tube or one of the Quest issued polypropylene pour-off/transfer tubes. Do not transfer to conical tube. If unable to centrifuge within 1 hour of collection, store tube on ice. Store frozen. Note: Quest Diagnostics does not perform this test for individuals under the age of 18. Pre-test and post-test counseling is strongly recommended. |
| Transport container | Transport tube |
| Transport temperature | Frozen |
| Specimen stability | Room temperature: Unacceptable Refrigerated: 72 hours Frozen -20° C: 32 days Frozen -70° C: 77 days |
| Reject criteria | Moderate or gross hemolysis • Specimen collected in a glass, polystyrene, or polycarbonate tube |
Reference Range(s)
| ABeta 42 | Not established | pg/mL |
| ABeta 40 | Not established | pg/mL |
| ABeta 42/40 Ratio | ≥0.170 |
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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