Alzheimer’s Disease Biomarker Panel, Cerebrospinal Fluid




Test Mnemonic

ALZCSF

CPT Codes

  • 83520 - QTY (3)

Aliases

  • Alzheimer’s Disease Core Biomarkers, Cerebrospinal Fluid
  • Alzheimer’s Disease Biomarkers Phospho-Tau(181P) / Total-Tau / A Beta42 / Phospho-Tau(181P) Ratio / Total-Tau Ratio
  • Alzheimer’s Disease Biomarkers Phospho-Tau(181P) / Total-Tau / A Beta42 / Phospho-Tau(181P) Ratio / Total-Tau Ratio, Analysis and Interpretation

Performing Laboratory

Cleveland Clinic Laboratories

FDA Category

In Vitro Diagnostic


Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
2.5 mLCerebrospinal fluid (CSF)See note RefrigeratedCollection and transport MUST be done in the approved polypropylene CSF tube (Sarstedt CSF False Bottom Tube, Ref 63.614.625). Other tubes for collection and transport are not acceptable. Do NOT transfer or aliquot the CSF sample. NOTE: Do not use the first 2 mL of CSF collection for this test.

Minimum Specimen Requirements

Volume Type Container Collect Temperature Transport Temperature Special Instructions
2.5 mL     

Stability

Environmental Condition Description
Ambient5 days
Refrigerated14 days
Frozen8 weeks NOTE: Do NOT freeze at < -60 C.

Days Performed

1 day per week

Turnaround Time

1 - 8 days

Methodology

Name Description
Electro Chemiluminescence Immunoassay (ECLIA) 

Reference Range

Abeta42
Sex Age From Age To Type Range Range Unit
       Normal>= 564.2pg/mL
Phospho-Tau (181P)
Sex Age From Age To Type Range Range Unit
       Normal<= 31.30pg/mL
Phospho-Tau (181P) / Abeta42 ratio
Sex Age From Age To Type Range Range Unit
       Normal<= 0.0230 
Total-Tau
Sex Age From Age To Type Range Range Unit
       Normal<= 375.4pg/mL
Total-Tau / Abeta42 ratio
Sex Age From Age To Type Range Range Unit
       Normal<= 0.280 

Special Info

Low-binding polypropylene tubes (Sarstedt, Ref 63.614.625) MUST be used for this test. CSF samples that are collected or transported to the testing laboratory in any other tube are not acceptable and will be rejected. CSF samples that are underfilled will be rejected. Samples that are visibly hemolyzed are not acceptable.

Clinical Info

This test is intended for adult patients aged 55 years and older being evaluated for Alzheimer's disease (AD) and other causes of cognitive impairment.

Clinical Limitation

A positive pTau181/Abeta42 or tTau/Abeta42 ratio result in CSF does not establish a diagnosis of Alzheimer's disease (AD) and should always be interpreted in conjunction with clinical information. The performance of the test for African-American, Asian, and other races had high uncertainty due to the limited number of patients studied. Results should not be used for predicting development of dementia or other neurologic conditions or for monitoring responses to therapies.