Paroxysmal dyskinesias: causes, symptoms, diagnosis

Paroxysmal dyskinesia is a polyethological disease manifested by attacks of dystonic (as well as choreic, myoclonic and ballistic) movements and pathological poses without loss of consciousness. Until now, a unified classification of these seizures has not been created. The following criteria are used as classification criteria: the time of day in which attacks are observed (daytime - night), provoking factors (kinesiogenic - non-kinetic), duration of attack (short - long), heredity (family - acquired or primary - secondary).

The main clinical forms of paroxysmal dyskinesia:

1. Paroxysmal kinesiotogenic dyskinesia.
2. Paroxysmal non-kinesiogenic dyskinesia.
3. Paroxysmal dyskinesia, induced by physical exertion.
4. Paroxysmal hypnogenic dyskinesia.
5. Benign paroxysmal corticollis in infants.
6. Paroxysmal dyskinesias in the picture of alternating hemiplegia in children.
7. Psychogenic hyperkinesis of a paroxysmal nature.

Paroxysmal kinesiotogenic dyskinesia

Primary (hereditary and sporadic) kinesiotogenic dyskinesia begins in 80% of cases at the age of 8 to 17 years (variations from 1 year to 30 years and older are possible), is more common in men and is manifested by short attacks (in most cases less than 1 minute) of violent movements. A high frequency of seizures is characteristic: almost all patients suffer from daily single seizures; for many, they occur several times a day, and in the period of exacerbation - up to 100 a day and more often. One of the distinguishing features of paroxysmal kinesiotogenic dyskinesia is the provocation of seizures by movement. Usually this is a sudden unprepared automatic movement. Fright and start can also provoke an attack. Paroxysm develops on the side of the body on which the movement was made (usually by hand or foot). An attack that begins in the arm (or leg) can spread along the hemite or, more rarely, it is limited to one region of the body or even a part of it. In the same patient, left-sided, right-sided and bilateral seizures may alternate with an attack to an attack. In the motor picture of the attack, tonic and dystonic, less often others, movements and postures predominate.

Immediately before the attack, most patients experience a sensory aura in the form of a feeling of constriction, tingling, numbness, stiffness, crawling in the limb that will be involved in paroxysm. In the case of bilateral attacks, the aura is more often bilateral. Some patients report the possibility of some control over attacks: feeling the approach of an attack, some patients can prevent it, completely stopping all movements or holding the affected limb with the other hand. Sometimes the attack can be prevented by slow movement, turning it from automatic to highly controlled. Almost all patients report a refractory period, when for a short time after an attack (usually 5-20 minutes) no provoking stimuli are able to cause an attack. Typical preservation of consciousness in the attack and the lack of postpristupnoy confusion. Neurological status during an attack and during the inter-attack period without deviations from the norm.

Paroxysmal noncinesiogenic dyskinesia

Primary (hereditary and sporadic) non-synesial dyskinesia begins almost exclusively in childhood (in two-thirds of cases the debut of the disease falls on the age of before 5 years), among the diseased predominate males. This form is characterized by more rare attacks (once a week or 2-3 times a month). The seizures themselves are more prolonged: from 5 minutes to 4-5 hours and more. In adulthood there is a tendency to spontaneous improvement. Attacks develop either spontaneously, or are provoked by alcohol, coffee, analgesics, stress, menstruation and other factors. It is also characterized by a sensory aura and partial control over attacks (most often with the help of relaxation). The motor pattern of the attack is almost the same as with kinesiogenic dyskinesia.

Paroxysmal dyskinesia, induced by physical exertion

Paroxysmal dyskinesia induced by physical exertion is isolated in a separate form, since dyskinesia attacks with this form are provoked only by prolonged physical exertion, paroxysms are often involved in the legs (dystonic spasm), and the attack lasts for 5-30 minutes. Such an attack is never provoked by sudden movement. The frequency of seizures varies from 1 per day to 2 per month. This duration and frequency of seizures served as the basis for calling this form "intermediate."

Paroxysmal hypnogenic dyskinesia

Paroxysmal hypnogenic dyskinesia is characterized by night attacks, which are phenomenologically similar to daytime paroxysmal dyskinesias. Attacks often appear in the 3-4 stages of slow sleep and are manifested by choreic, dystonic, myoclonic and ballistic movements without disturbing consciousness. It is noticed that sometimes attacks are provoked by the movement of the body in a dream. There are also short (15-45 sec) and long-lasting seizures (from 2 minutes to 2 hours). According to most researchers, short nighttime attacks of "dyskinesia" are a kind of epileptic seizures. Long-term attacks refer to parasomnias. Attacks can be observed every night and sometimes repeatedly overnight (more than 10). Most often observed bilateral generalized seizures. Sporadic and family forms of hypnogenic paroxysmal dyskinesia are described. With frequent attacks, it is possible to have sleep deprivation due to seizures and compensatory daytime sleepiness.

All the above variants of paroxysmal dyskinesia belong to primary (hereditary or sporadic) forms. EEG and neurologic status in the interictal period usually do not show abnormalities. EEG during an attack is difficult to document because of artifacts associated with movements (dyskinesia). The secondary (symptomatic) forms of the above dyskinesia are described in many diseases. These include: infantile cerebral palsy, multiple sclerosis, hypoparathyroidism, pseudohypoparathyroidism, hypoglycemia, thyrotoxicosis, cerebral infarction (including systemic lupus erythematosus), transient ischemic attacks, hemorrhage to the medulla oblongata, arterio-venous malformation, traumatic brain injury, encephalitis (including HIV infection), iatrogenic (cerulek, methylphenidate) and toxic (cocaine, alcohol) forms. Here, more varied EEG changes and neurological status are possible. With all the above-mentioned forms of paroxysmal dyskinesia, the therapeutic effect of anticonvulsants is noted.

Benign paroxysmal corticollis in infants

Benign paroxysmal corticollis in infants is even more rare and develops, as the name suggests, only in infants. The disease occurs in the first months of life and is manifested by repeated episodes of twitchings and torticollis lasting from 15 minutes to several hours. These episodes are sometimes accompanied by nausea, vomiting and ataxia. Attacks are repeated on a monthly basis and spontaneously cease in the coming years. Genetic predisposition to migraine is characteristic. Migraine develops in many patients with benign paroxysmal corticollis. EEG and caloric test during an attack of corticollis usually show a normal picture.

Paroxysmal dyskinesias in the picture of anthermal hemiplegia in children

Altening hemiplegia in children refers to rare diseases and is characterized by: the debut of the disease before the age of 3 (sometimes at the age of 3 months); repeated attacks of hemiplegia (with alternation of the affected side of the body) lasting from several minutes to several days; presence of other paroxysmal phenomena (dystonia, chorea, nystagmus, vegetative disorders in the form of tachycardia, mydriasis and hyperhidrosis during hemiplegia or independently of it); episodes of bilateral hemiplegia; improvement during sleep and progressive deterioration of neurological and mental functions.

The first attacks can be hemiplegic, dystonic, or both include both. Short episodes of nystagmus lasting 1-3 minutes are often accompanied by dystonic (hemidistonia or opisthotonus) and hemiplegic seizures. Hemiplegia usually has a flaccid character, regardless of whether it is superimposed on it or not. Attacks begin suddenly, which often serves as an excuse for erroneous diagnosis of epilepsy or stroke with hemiplegia. Generalized tonic-clonic seizures can sometimes appear in children with this disease at an older age. During prolonged seizures, hemiplegia can "shift" from one side of the body to the other or involve both halves of the body. The arms are usually more affected than the legs. Walking can be violated not very rudely. Hemiplegia disappears during sleep and comes back on waking, but usually not immediately. Sometimes there are headaches at the beginning of an attack. Flunarizine in some children reduces the frequency of seizures.

Characteristic retardation of mental development. Neurological status is characterized by a step-like deterioration, since restoration of functions after individual seizures may be incomplete. The most common symptoms are dystonia, spasticity, pseudobulbar paralysis and ataxia. MRI reveals a progressive atrophy of the cerebellar worm. Most cases (except one family) are sporadic.

Differential diagnosis is performed with paroxysmal dyskinesia, hemiplegic migraine, epilepsy, stroke, doparepnesivnoy dystonia (dystonia, sensitive to dopamine).

Psychogenic hyperkinesis of a paroxysmal nature

Psychogenic hyperkinesis occurs in about 50% of cases paroxysmally. Paroxysmal manifestations in general are extremely characteristic of psychogenic disorders. Tremor accounts for approximately 50% of all psychogenic hyperkinesia, dystonia - 18%, myoclonus - 14%, "parkinsonism" - 7%, other types of psychogenic dyskinesia occupy about 11% of the total number. For all psychogenic hyperkinesis is very characteristic: a sudden start with a clear provocative event (emotionally debut); multiple motor disorders (pseudo-cuts, dysphonia, pseudo-copying, spasm of convergence, pseudo-seizures, dysbasia, mutism, etc.); variable and transient motor disorders, fluctuating during one inspection or from inspection to inspection; motor manifestations do not correspond to known organic syndromology; hyperkinesis builds up when the examination is focused on the affected part of the body, and decreases when the patient's attention is distracted; often there is hyperexclusion or excessive starter reactions; hyperkinesis often responds to placebo or suggestion; there is a characteristic syndromic environment (a variety of functionally-neurological "stigmata") and typical mental disorders; Hyperkinesis is eliminated by psychotherapy or discontinued when the patient does not suspect that they are watching him.

In general, any psychogenic hyperkinesis differs from the organic one by four factors: the motor pattern, the dynamics of hyperkinesis, the syndromic environment, and the course of the disease. For a well-founded diagnosis, a positive diagnosis of psychogenic ("neurotic") disorder is important and the elimination of classical forms of organic hyperkinesis. Currently, the criteria for the diagnosis of psychogenic tremor, psychogenic myoclonus, psychogenic parkinsonism, psychogenic dystonia, and criteria for diagnosing the combination of psychogenic and organic hyperkinesis have been developed; the criteria of proven (documented), reliable, probable and possible psychogenic motor disorders are formulated. However, their presentation is beyond the scope of this section of the book.

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