Dementia biomarkers (CSF)

Referred to Berkshire & Surrey Pathology Services, Frimley Park Hospital NHS Foundation Trust, Portsmouth Road, Frimley, Surrey GU16 7UJ

Alternative names, keywords

Amyloid beta 40, amyloid beta 42, a-beta, Aβ40, Aβ42, Aβ ratio, Tau protein, total tau, t-tau, phosphorylated tau, phospho tau, p-tau.

Not to be confused with tau transferrin (beta-2 transferrin) which is a different test used to detect CSF leaks (e.g. into nasal fluid)

Samples required

0.25 mL of CSF (minimum), must be collected in polypropylene tubes and brought to lab immediately.

DO NOT put the CSF in a Vacuette® tube.

Test indications

For the investigation of dementias including Alzheimer's disease.

42/ Aβ40 ratio is the recommended first-line test for Alzheimer's. Total-tau is a marker for neurodegeneration; raised total tau occurs in several neurodegenerative conditions and may be very high where there is ongoing neuronal degeneration or destruction. Phospho-tau is a marker for tangle pathology as seen in Alzheimer’s disease and is not usually raised in other conditions.

Please specify clearly which tests are required.

Reference range

See reports for reference ranges and interpretation.

Turnaround time

Referral lab quotes turnaround time of 8 days, however additional time must be allowed for packing, dispatch and delivery of sample, and return and processing of results.


Biochemistry (Referrals)