Frontotporal dementia

Frontotporal dementia refers to sporadic hereditary diseases in which frontal and temporal lobe lesions are affected, including Pick's disease.

Fracture-related dementia (FTD) accounts for up to 10% of all dementia. The onset of this neurologic disease refers to a younger age (55 to 65 years) than the onset of Alzheimer's disease. Frontotporal dementia is equally common for men and women. Peak's disease as one of the variants of frontotemporal dementia from a pathomorphological point of view is characterized by pronounced atrophy of brain substance, loss of neurons, gliosis, the appearance of abnormal neurons (Pick cells) containing inclusions (Pike's body).

[1], [2]

Causes of frontotemporal dementia

Approximately 1/2 cases of frontotemporal dementia are hereditary, the most significant mutations occur in chromosome 17q21-22, which leads to disorders in the structure of tauprotein, therefore, frontotemporal dementia means cautaupatia. Some experts refer to progressive supranuclear palsy and corticobasal degeneration to frontotemporal dementia, because they are based on similar pathological changes and genetic mutations that damage tauprotein. Symptomatology can not always correspond to genetic mutations and pathological manifestations of the disease, and vice versa. For example, similar mutations cause the manifestation of frontotemporal dementia in one family, and members of another family have symptoms of corticobasal degeneration, Peak cells may be absent in patients with typical manifestations of Pick's disease.

[3], [4], [5]

Symptoms of frontotemporal dementia

In general, frontotemporal dementia largely affects the patient's personality characteristics, behavior and speech functions (syntax and fluency) and less memory compared to Alzheimer's. Abstract thinking and attention (retention and switchability) are lost, and response reactions are disorganized. The orientation has been retained, but the reproduction of information may be weakened. Locomotor skills are usually preserved. Patients have difficulty with the sequence of tasks, despite the fact that the fulfillment of visual-spatial and constructive problems suffers to a lesser extent.

Signs of disinhibition of the frontal cortex (grasping phenomena, sucking, proboscis reflexes, superciliary (glabellar), palmmental (palmar) reflexes) appear in later stages of the disease, but may also be present in other types of dementia. Some patients develop a clinical picture of motor neuron disease with generalized muscle atrophy, weakness, fasciculations, bulbar symptoms (including dysphagia, dysphonia, difficulty chewing), which increases the risk of aspiration pneumonia and early death.

Frontal variant of frontotemporal dementia

In connection with the defeat of the structures of the basis of the frontal lobe, the social behavior and personal characteristics of the patient suffer. Patients become impulsive and lose control over social constraints (including they may become prone to theft), neglect personal hygiene. Some have manifestations of the Kluver-Bussy syndrome, including emotional stupidity, hypersexuality, hyperorality (including bulimia, sucking and spitting with the lips), visual agnosia. There is a decrease in the ability to concentrate, inactivity and mental rigidity. Behavior becomes stereotyped (the patient can walk to the same place every day). Patients can collect and manipulate random objects (recycling behavior). Verbal production is reduced, echolalia, perseveration (inappropriate repetition of answers to questions) and ultimately develops mutism.

Primary progressive aphasia

Speech functions are lost due to asymmetric (more left-sided) anterolateral temporal atrophy; the hippocampus and memory suffer moderately. Most patients have difficulty in choosing words. Attention (including a serial digital account) can be significantly impaired. Many patients have aphasia with reduced smoothness of speech and difficulties in understanding speech structures, and often there is uncertainty about speech production and dysarthria. In some patients aphasia as a monosymptom develops after 10 years or more from the onset of the disease, in others the global deficit occurs within a few years.

Semantic dementia is one of the types of primary progressive aphasia. In cases where the left hemisphere of the brain is damaged to a greater extent, the ability to understand words progressively is lost. Speech remains smooth, but it lacks meaning (for example, similar or related terms are used despite the presence of specific names of objects). In cases where the right hemisphere suffers more, patients develop a progressive anomie (failure to name the subject, and prosopagnosia (inability to recognize familiar faces), they can not remember topographic relationships.Some patients with semantic dementia have Alzheimer's disease.

Diagnostics of front-temporal dementia

Diagnosis is based on the establishment of typical clinical signs of the disease. As with other types of dementia, cognitive deficits are assessed in patients. KG and MRI are performed to determine the localization and severity of brain atrophy and exclude other possible causes of its occurrence (including brain tumors, abscesses, stroke). Frontotporal dementia is characterized by pronounced brain atrophy, sometimes the degree of thinning of the temporal and frontal lobe grooves reaches the thickness of a sheet of paper. Since MRI and CT can not detect areas of prevalent brain cortical atrophy until late stages of development of the front-temporal dementia, neuroimaging can be less useful for the exclusion of Alzheimer's disease (in which the hippocampus and parietal lobe are predominantly damaged in the early stages), but the clinical differences between these diseases allow distinguish them. For example, primary progressive aphasia differs from Alzheimer's disease with memory preservation and spatial-visual function with loss of the syntactic component of speech and its smoothness.

[6], [7], [8], [9]

Treatment of frontotemporal dementia

Specific treatment of Pick's disease does not exist. Usually, supportive care is provided.

Forecast of anterior temporal dementia

Frontotporal dementia usually progresses gradually, but the rate of progression can vary; if the symptomatology is limited to speech dysfunction and language problems, progression to the level of global dementia may be slower.

[10], [11]