01730 - Dementia assessment

Beta-amyloid (1-42) and tau protein play a central role in the pathogenesis of Alzheimer's disease.

Tau proteins are used as markers of neurodegenerative dementia processes. Under physiological conditions, tau proteins appear to stabilise neuronal microtubules, whose (often age-related) destruction is a typical feature of neurodegenerative processes, as well as neuronal damage caused by inflammatory, vascular and tumour processes. Under pathological conditions, increased concentrations of tau proteins are measured in the cerebrospinal fluid.

Several years before the elevation of total tau protein and phospho-tau protein in the CSF, a decrease in beta-amyloid (1-42) may be detectable in the CSF, which may correlate with the formation of Alzheimer plaques.

Elevated levels of tau protein also occur in the following situations: M. Alzheimer's disease, Lewy body disease, corticobasal degeneration, progressive supranuclear gaze palsy, frontotemporal dementia, vascular dementia, Creutzfeldt-Jakob disease, traumatic brain injury (highly elevated), cerebral infarcts.

Therefore, the combined determination of the parameters beta-amyloid-1-42 and total tau (hTau) or beta-amyloid-1-42 and phospho-tau (pTau) is recommended.
The additional determination of the beta-amyloid (1-42)/(1-40) quotient significantly improves the laboratory diagnosis of Alzheimer's dementia, as it enables a better differentiation from other forms of dementia.