The Alzheimer’s disease is manifested by memory problems, but not only. Doctors realized that other signs could announce the development of this slowly progressive neurodegenerative disease. “In the years preceding the obvious manifestations, we sometimes find unusual character disorders, such as the appearance of great anxiety, irritability, hyperactivity or, on the contrary, apathy”, explains Professor Vincent Camus, psychiatrist, CHRU Bretonneau (Tours), co-responsible for the Resource and Research Memory Center (CMRR) in the Center region. Signs that are often more difficult for the family to bear than memory problems, at least at first.
Today, the diagnosis is made on observations
There is no test whose positive result indicates Alzheimer’s disease. The diagnosis is established by a specialist in memory disorders from several evaluations : a clinical examination (postural disorders, oculomotor disorders…), a neuropsychic assessment (based on tests evaluating memory and language), and an ibrain magic (scanner, MRI, brain scan).
In some cases, this assessment is not enough to make the diagnosis and the specialist suggests a lumbar puncture to measure specific proteins in the cerebrospinal fluid (TAU proteins, beta-amyloid proteins). Their concentration is correlated with the presence of specific abnormalities in the brain.
Tomorrow, we will spot the abnormalities in the brain
CT and MRI can only identify an indirect sign of the disease: cerebral atrophy. Hence the interest in new molecular imaging techniques which make it possible to visualize cerebral abnormalities typical of the disease (amyloid plaques and neurofibrillary degeneration).
New radiotracers (substances injected into a vein in the arm before the examination) bind electively to them and then emit signals identified by a sophisticated device (positron emission tomograph or PET). The radiologist can thus observe live in the brain of the sick person the anomalies described by Dr. Alois Alzheimer in 1903 under the microscope. It was at the time from brain slices of deceased patients. Used in the context of research, in particular to test the effectiveness of treatments under study, this type of examination could become more important in the future by making it possible to identify the disease at an earlier stage. that is, before the appearance of signs of mental confusion.
Why early diagnosis is important
“I understand that in the absence of specific treatments, which is the case today, the question arises of the interest of early diagnosis, explains Prof. Caroline Hommet, head of the Resource Memory Center and (CMRR), Tours Bretonneau University Hospital, but this has several advantages: providing information on the disease, supporting the patient and his family, avoiding medication errors (benzodiazepines are not recommended), but using others that will help to live better, delay entry into an institution by setting up appropriate care as the disease progresses.And then let’s not forget that many therapeutic molecules are currently in development in laboratories.
Thanks to Pr Denis Guilloteau, head of the nuclear medicine department, CHRU Bretonneau.
Read also :
Alzheimer’s: gardening helps restore memories
Alzheimer’s: 11 new genes discovered in three years
A robot to help Alzheimer’s patients
