Blood test for the diagnosis of parkinsonism

In the diagnosis of atypical parkinsonism, a spinal puncture can be replaced by a blood test

Anna Stavina, XX2 century

In order to distinguish Parkinson's disease from diseases with similar symptoms, patients are now forced to undergo a painful and not entirely safe procedure for collecting cerebrospinal fluid. However, according to the authors of the study published in Neurology (Hansson et al., Blood-based NfL), a lumbar puncture may be replaced in the future by a conventional blood test. At the same time, the accuracy of the survey results will not change.

Parkinson's disease is characterized by tremor, stiffness and slowing of movements, as well as problems with coordination and balancing when walking. Less obvious manifestations of the disease include depression, insomnia and increased fatigue. But there are a number of neurological diseases that are very similar in symptoms to Parkinson's disease, but they are not. They are united under the name of "atypical Parkinsonism". Characteristic "Parkinsonian" symptoms in this case are considered as a syndrome, that is, as a set of signs that can develop as a result of various diseases.

"It is very difficult to distinguish Parkinson's disease from atypical Parkinsonism, especially in the early stages of the disease. Especially if a neurologist specializing in motor disorders is not working with the patient," says the lead author of the study, Dr. Oskar Hansson, a neurologist, associate professor at Lunds universitet in Sweden.

However, correct diagnosis is extremely important, since atypical Parkinsonism usually progresses much faster and is more severe than Parkinson's disease. At the same time, patients with atypical Parkinsonism usually do not respond to treatment with standard antiparkinsonian drugs.

To simplify the process of diagnosis, Dr. Hansson and his colleagues have developed a special blood test. In fact, it is a modification of the existing analysis of cerebrospinal fluid. In both cases, the concentration of light chains of neurofilaments, tubes that make up the skeleton of neurons is analyzed. With the mass death of nerve cells, neurofilaments are released and can be detected in the cerebrospinal fluid, as well as, as demonstrated by a new study, in the patient's blood.

To test the hypothesis, the researchers recruited 244 participants with Parkinson's disease and 181 participants with atypical Parkinsonism. Another 79 healthy volunteers made up the control group.

Parkinson's disease is a slowly progressive chronic neurological disease characteristic of the older age group. It refers to degenerative diseases of the extrapyramidal motor system. It is caused by the progressive destruction and death of neurons that produce the neurotransmitter dopamine, primarily in the substantia nigra, as well as in other parts of the central nervous system. Insufficient dopamine production leads to the activating effect of the basal ganglia on the cerebral cortex and the appearance of characteristic symptoms.
Parkinson's disease owes its name to the French neurologist Jean Charcot (fr. Jean-Martin Charcot). He suggested naming it after the British doctor and author of the Essay on Trembling Paralysis, James Parkinson, whose work was not properly appreciated during his lifetime.

The second subgroup included patients with multiple systemic atrophy, progressive supranuclear paralysis and corticobasal degeneration. The concentration of light chains of neurofilaments in the blood of the members of the second subgroup was significantly higher than in the blood of the rest of the study participants.

At the same time, the accuracy of the new test was comparable to the accuracy of the analysis of cerebrospinal fluid. It made it possible to distinguish Parkinson's disease from atypical Parkinsonism, including in patients who were in the early stages of the disease.

Dr. Hansson hopes that in the future the new blood test will become a standard diagnostic procedure that will be carried out, including for patients who do not show typical symptoms or do not respond to standard therapy.

Portal "Eternal youth" http://vechnayamolodost.ru  09.02.2017