A commercial test is coming to discriminate Alzheimer’s from other dementia. But it is not intended for patients: only doctors will be able to administer it.
A simple blood examination will favor Alzheimer’s differential diagnosis in US patients with the symptoms of a dementia. The FDA has given the green light to a test that detects in the plasma, the liquid component of the blood, the traces of the two identification proteins of Alzhimer’s disease, the beta-amyloid and the Tau. This is the first commercial examination to be approved against this pathology, but it will not end up directly in the hands of the patients. Will be administered by the doctorsand in well -defined conditions.
What is called (and what finds) the new test for Alzheimer
The test has the commercial name of Lumipulse G PUU217/ß-Amyloid 1-42 Plasma Ratio And it is produced by the Japanese biotechnology multinational Fujirebio Diagnostics. AND A simple blood test which calculates the numerical relationship between the levels of beta amyloid protein (the one that aggregates in the characteristic neurotoxic plates) and Tau (head of the neurofibrillary tangles, other harmful deposits) detected, and compares them with the presence or absence of amyloid plates evident from the pet. The test goes in search of two particular forms of the two proteins, the PTAU217 and the Beta-Hamiloid 1-42.
To whom the exam is directed
The new test will be prescribed by doctors a patients over 55 years old Already affected by the symptoms of a dementia, possibly after they have already undergone neuropsychological tests to ascertain a cognitive decline and a brain scan to exclude the presence of stroke injuries or brain cancer.
Distinguish Alzheimer’s from other dementia
Pet (Positroni emission tomography) is a diagnostic technique that uses a radioactive tracking to analyze the metabolic functions of the tissues, and is the election exam for the diagnosis of Alzheimer’s. This type of scan allows you to view the deposition of amyloid plates in the brain and is usually integrated with The analysis of the cerebrospinal fluidthe fluid surrounding the brain and spinal cord and that flows near the sick brain tissues.
If it detects a low level of beta-amyloid while the pet indicates an accumulation of amyloid deposits in the neurons of the cerebral cortex, then it is very likely to be in the presence of Alzheimer’s disease.
However, these exams are not always available: PET is a very expensive diagnostic technique, and the analysis of the Liquor an invasive procedure that takes place through a lumbar puncture. The new test can detect the presence of the proteins associated with Alzheimer and direct the doctors to the prescription of one or the other technique to confirm the diagnosis.
In short, it is one more tool To refine the diagnosiswhich should not be used independently but must be integrated with the methodologies already available.
How accurate is the new test for Alzheimer?
The examination has an accuracy equal to almost 92% of that of a pet or an examination of the cerebrospinal liquid in identifying people with Alzheimer’s. And it reaches almost 97% of specificity compared to the other two exams in finding patients not affected by Alzheimer. In less than 20% of cases – the exam was validated on 499 subjects – returns an indeterminate result. Just the existence of false positive or false negatives (and the risks that an incorrect diagnosis of Alzheimer’s, or absence of it, could involve) requires that the test is administered in union with other diagnostic techniques.
More early care and diagnosis
Other blood tests have been used in research contexts to trace Alzheimer’s biomarkers before now. The one approved, however, is the first to receive a go -ahead for trade, albeit with the limitations we mentioned. The new test will allow a greater number of patients to receive an accurate diagnosis for the form of dementia they suffer from – distinguishing, for example, between Alzheimer’s, vascular dementia or dementia in Lewy bodies, another progressive neurogenerative disease. And, with the correct diagnosis in hand, to face early therapies with the new generation of anti-alzheimer drugs, capable of slowing down the progression of dementia a little.
Excluding people not affected by Alzheimer’s from treatments is equally important: these therapies can in fact give serious side effects.
