This test is not approved for use by New York state clients.
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
1 mL (Note: This volume does not allow for repeat testing.)
Lavender-top (EDTA) tube
Lavender-top (EDTA) tube
Lavender-top (EDTA) tube< tube
Draw blood into an EDTA tube. Separate plasma from blood via centrifugation (>1500g for 10 minutes) within 40 minutes after blood collection. Transfer EDTA to a Labcorp polypropylene transport tube and seal.
Plasma samples may be stored for up to 6 hours at 2°C to 8°C prior to placing in dry ice (for shipment) or an ultra-low freezer transfer (< -60°C).
Do not freeze samples at -20°C; analyte stability is not preserved.
Hemolysis; lipemia; heat-treated specimen; gross bacterial contamination; wrong tube type; not stored at proper temperature
The plasma A42/40 ratio is intended for use as an adjunct to diagnostic evaluations of Alzheimer's disease, including neurological and cognitive performance examinations and PET neuroimaging.
The diagnostic hallmarks of Alzheimer's disease (AD) are extracellular deposits of beta amyloid plaques and neurofibrillary tangles observed in the cortex and limbic brain region upon autopsy. The major molecular components of beta amyloid plaques and neurofibriiary tangles are beta amyloid 1-42 and tau protiens, respectively. The major beta amyloid metabolic products beta amyloid 1-42 and beta amyloid 1-40 are generated by beta and secretase enzymatic cleavage of the amyloid precursor protein (APP), with more hydrophobic beta amyloid 1-42 peptide aggregating to form amyloid plaques. Reduced concentrations of beta amyloid 42 in EDTA plasma are associated with increased retention of beta amyloid tracers in the brain beta amyloid plaques observed with positron emisson tomography (PET), and are inversely correlated. Low beta amyloid 42/40 ratios are more associated with patients having a clinical diagnosis of AD or beta amyloid PET positivity, whereas higher ratios are less associated with AD diagnosis or beta amyloid PET positivity.
Samples that contain fibrin, red blood cells and other insoluble objects may lead to inaccurate results.
This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.
Samples that contain fibrin, red blood cells and other insoluble objects may lead to inaccurate results.<.
Sysmex chemiluminescence enzyme immunoassay (CLEIA)
enzyme immunoassay (CLEIA)
|Order Code||Order Code Name||Order Loinc||Result Code||Result Code Name||UofM||Result LOINC|
|505725||Beta Amyloid 42/40 Ratio||505721||Beta-amyloid 42/40 Ratio||Pending|
|505725||Beta Amyloid 42/40 Ratio||505722||Beta-amyloid 42||pg/mL||33200-7|
|505725||Beta Amyloid 42/40 Ratio||505723||Beta-amyloid 40||pg/mL||70073-2|
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