| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Beta-Amyloid 42/40 Ratio, CSF
Test Code94627
CPT Codes
82542<br>This test is not available for New York patient testing
Preferred Specimen
1.2 mL CSF collected in a 12 X 75 mm polypropylene tube
Minimum Volume
0.6 mL
Instructions
Collect and transport CSF in a 12 X 75 mm polypropylene tube. Store frozen.
Quest Diagnostics does not perform this test for individuals under the age of 18. Pre-test and post-test counseling is strongly recommended.
Transport Temperature
Frozen
Specimen Stability
Room temperature: 72 hours
Refrigerated: 5 days
Frozen: 31 days
Refrigerated: 5 days
Frozen: 31 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Specimen collected in a glass, polystyrene or polycarbonate tube • Hemolysis • Moderately and grossly icteric • Grossly lipemic
Methodology
Liquid Chromotography/Tandem Mass Spectrometry (LC/MS/MS)
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
Set up: Sun; Report available: 3-10 days
Reference Range
See Laboratory Report
Clinical Significance
This LC-MS/MS assay measures beta-amyloid 40 (AB40) as well as AB42 in cerebrospinal fluid (CSF), rather than AB42 alone. This permits the normalization of beta amyloid levels circulating in CSF in different patients. Using the ratio of beta-amyloid 42/beta-amyloid 40, improves sensitivity and specificity for detecting Alzheimer's disease.
Performing Laboratory
| Quest Diagnostics Nichols Institute-San Juan Capistrano, CA |
| 33608 Ortega Highway |
| San Juan Capistrano, CA 92675-2042 |
Last Updated: March 17, 2023
