What is analysed?
Beta-amyloid 42 (Aß42) and tau protein are two biomarkers found in cerebrospinal fluid (CSF) associated with the development of Alzheimer's disease. Aß42 is a peptide, while tau protein is a structural brain protein.
The Aß42 and tau protein test measures the concentration of Aß42 and tau protein in CSF.
What does the result mean?
The result indicates the concentration of Aß42 and tau protein in CSF.
Why conduct the analysis?
The Aß42 and tau protein test is conducted to differentiate Alzheimer's disease from other forms of dementia.
When to conduct the analysis?
The Aß42 and tau protein test is conducted when symptoms of neurodegenerative conditions, such as memory loss, are observed.
What sample is required?
A sample of CSF, obtained through a lumbar puncture (spinal tap), is required.
Is any prior preparation necessary?
No prior preparation is required.
How is it performed?
The collected sample is sent to a laboratory, where it is analysed using enzyme-linked immunosorbent assay (ELISA) and mass spectrometry techniques to quantify Aß42 and tau protein levels in CSF.
What are the normal values?
| Biomarker | Normal range |
|---|---|
| Aß42 | ≥ 500 pg/mL |
| Tau protein | < 375 pg/mL (CSF) |
What does having altered values mean?
• Low Aß42 and high tau protein levels indicate neurodegenerative processes associated with Alzheimer’s disease.