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Test ID ADEVL Alzheimer Disease Evaluation, Spinal Fluid

Specimen Required

Patient Preparation: For 12 hours before specimen collection do not take multivitamins or dietary supplements containing biotin (vitamin B7), which is commonly found in hair, skin, and nail supplements and multivitamins.

Supplies: Alzheimer's Disease Evaluation (ADEVL) Collection Kit (T836)


Preferred: Sarstedt CSF False Bottom Tube 63.614.625 (2.5 mL)

Acceptable: Sarstedt 72.703.600 (1.5 mL) or Sarstedt 72.694.600 (2 mL)

Specimen Volume: 1.5 to 2.5 mL

Collection Instructions:

1. Perform lumbar puncture and discard the first 1 to 2 mL of cerebrospinal fluid (CSF).

2. Collect CSF directly into one of the listed collection tubes until the tube is at least 50% full.*

3. Send CSF specimen in original collection tube. Do not aliquot.

Note: Polystyrene collection tubes are not acceptable. Exposure of CSF to polystyrene tubes may result in falsely low Abeta42 concentrations. For more information see Cautions.

*The Alzheimer's Association consensus protocol for handling of CSF for clinical measurements of Abeta42 and tau recommends using the drip method for CSF collection and directly collecting into a low bind polypropylene tube. Although some clinicians prefer the syringe pull method due to speed of collection, the drip method reduces the risk of Abeta42 binding to the plastic of any syringe used.

Useful For

Assessment of adults with cognitive impairment being evaluated for Alzheimer disease and other causes of cognitive impairment


These assays should not be used to predict the development of dementia or other neurologic conditions or to monitor response to therapies.

Method Name

Electrochemiluminescent Immunoassay (ECLIA)

Reporting Name

Alzheimer's Disease Evaluation, CSF

Specimen Type


Specimen Minimum Volume

See Specimen Required

Specimen Stability Information

Specimen Type Temperature Time Special Container
CSF Refrigerated (preferred) 14 days BlueTop SARSTEDT
  Frozen  60 days BlueTop SARSTEDT
  Ambient  12 hours BlueTop SARSTEDT

Reference Values

Beta-amyloid (1-42) (Abeta42): >834 pg/mL

Total-Tau: ≤238 pg/mL

Phosphorylated-Tau 181: ≤21.6 pg/mL

p-Tau/Abeta42: ≤0.028

Day(s) Performed

Tuesday, Friday

Report Available

1 to 4 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information

83520 x 3

LOINC Code Information

Test ID Test Order Name Order LOINC Value
ADEVL Alzheimer's Disease Evaluation, CSF 98492-2


Result ID Test Result Name Result LOINC Value
PTABR p-Tau/Abeta42 41027-4
ADINT AD Interpretation 69048-7
AB42P Abeta42 33203-1
TTAUP Total-Tau 30160-6
PTAUP Phospho-Tau(181P) 72260-3


If not ordering electronically, complete, print, and send a Neurology Specialty Testing Client Test Request (T732) with the specimen.