Typical epileptic seizures ("standard clinical model of convulsive generalized tonic-clonic seizure") are characterized by a sudden onset, short (most often) duration, periodicity of occurrence, stereotyped manifestations, presence of seizures as the main manifest sign, presence of phases (tonic and clonic) in the attack , a violation of consciousness. With the correct selection of the drug is characterized by the therapeutic effect of anticonvulsants (in most cases). However, occasionally epileptic seizures can occur without typical epileptic phases, without characteristic generalized seizures and even with conserved consciousness (for example, some variants of frontal epileptic seizures). Epileptic activity on the EEG is also not always found. The epileptic nature of the attack is indicated by such features as the presence of postictal changes in consciousness and an electroencephalogram; reaction to sleep deprivation, which allows to detect EEG signs of epilepsy; the presence of psychosensory, affective and behavioral symptoms characteristic of the ictal period of epilepsy, making the diagnosis of epilepsy unquestionable. Sometimes, confirmation of the diagnosis of epilepsy requires a polygraphic recording of night sleep or more sophisticated methods of recording the bioelectrical activity of the cortex and subcortical structures of the brain. Additional indirect confirmation of the epileptic nature of the attack is the exclusion of other possible causes of the attack.
Febrile seizures in children are a variant of epileptic seizures and reflect an increased convulsive readiness, indicating the risk of later typical epileptic seizures (especially with familial complications of febrile seizures and epilepsy) with a progressive course. The likelihood of epilepsy increases with a high frequency of febrile seizures and especially with the status of their flow.
Paroxysmal dyskinesia (the obsolete name "paroxysmal choreoathetosis") is a heterogeneous group of disorders characterized by attacks of involuntary movements and pathological poses that proceed without disturbance of consciousness.
There are six forms of paroxysmal dyskinesia:
- Paroxysmal kinesiotogenic dyskinesia.
- Paroxysmal non-kinesiogenic dyskinesia.
- Paroxysmal dyskinesia, induced by physical exertion.
- Paroxysmal hypnogenic dyskinesia.
- Paroxysmal benign corticollis in infants.
- Paroxysmal dyskinesias in the picture of alternating hemiplegia in children.
Kinesiogenic seizures are provoked by unprepared movement, flinches, onset of walking, etc. In the majority, kinesiogenic seizures are classified as short (usually 10-20 seconds); they are characterized by a high incidence of seizures (sometimes more than 100 per day). Nekinesiogenic seizures are provoked by emotional stress, intellectual tension, pain; often they develop spontaneously for no apparent reason. Nekinesiogenic seizures in 100% are long (from 1 to several hours); they occur much less often (from 1 a day to 1 a week or 1 in a few weeks). A special form of seizures is also singled out: it is sometimes called "intermediate", because their duration is 5-30 minutes, and the attack itself is provoked, strictly speaking, not by movement, but by prolonged physical exertion.
With all forms of paroxysmal dyskinesia, in about 80% of cases it is possible to identify certain harbingers of the attack ("aura") in the form of sensations of numbness, discomfort, stiffness and tension of certain muscle groups, from which the attack usually begins. Kinesiopathic seizures begin in those muscles, the reduction of which provokes an attack. Usually it is the distal parts of the arms or leg muscles. Spasm of muscles during an attack can spread from the hand (or leg) to the entire body half, including the face and is manifested in this case by the hemisyndrome. But the attack can also be generalized. It is also possible to alternate from an attack of left-sided, right-sided and generalized paroxysms in the same patient.
The predominant element in the structure of the motor manifestations of the attack are dystonic spasms and dystonic postures, but tonic, choreic, myoclonic, ballistic or mixed movements are possible. Similar attacks in some patients develop only during sleep (hypnotic paroxysmal dyskinesia). Described sporadically and heritable forms. These attacks develop only in the phase of slow sleep, can be nightly and sometimes occur up to 10 or more times per night.
Many patients with paroxysmal dyskinesia experience relief after an attack, as they are well aware that there will be no time for an attack (refractory period).
There is a misconception that paroxysmal dyskinesias are manifested exclusively by motor symptoms. The attack is usually accompanied by anxiety, anxiety, a sense of fear. Permanent emotional disorders are also characteristic of the interictal period, which sometimes complicates differential diagnosis with psychogenic motor disorders.
All forms of paroxysmal dyskinesia are primary (sporadic and hereditary) and secondary. At primary forms in the neurological status the focal neurologic symptomatology is not revealed. Possible causes of secondary paroxysmal dyskinesias continue to be specified. Until recently, among these reasons, only three diseases were mentioned: infantile cerebral palsy, multiple sclerosis and hypoparathyroidism. Today the etiology of this syndrome includes, in addition to the above reasons, pseudohypoparathyroidism, hypoglycemia, thyrotoxicosis, cerebral infarction (including systemic lupus erythematosus), transient ischemic attacks, cerebral hemorrhage, arterio-venous malformation, craniocerebral trauma, encephalitis in the acute phase), HIV infection, iatrogenic (cerucal, methylphenidate, cisapride) and toxic (cocaine, alcohol, etc.) forms and some other causes (progressive supranuclear palsy, complex regional pain syndrome rum, spinal cord injury). Perhaps, the circle of these diseases has not completely closed yet and will expand.
EEG during an attack is usually filled with motor artifacts; in the same cases where the recording of the EEG is successful, in most cases there is no epileptic activity. It is characteristic that seizures, as a rule, respond to anticonvulsants (clonazepam, finlepsin, etc.).
For the diagnosis, it is important to be able to recognize typical dystonic postures in the extremities, EEG examination in the interstitial period and, if possible, in the attack. Sometimes it is useful to register a seizure.
According to the motor pattern, patients with paroxysmal dyskinesia resemble dystonia most often, and according to the paroxysmal nature of its manifestations are similar to epilepsy.
For paroxysmal dyskinesia is also characterized by a sudden onset, short (most often) duration, periodicity, stereotyped manifestations, the presence of "cramps" as the main manifest and, finally, the therapeutic effect of anticonvulsants. In addition, patients with paroxysmal dyskinesia often display various abnormalities in the EEG and even obvious epileptic encephalographic and / or clinical manifestations in the history of patients or their family members. The proposed strict criteria for differential diagnosis based on the EEG-registration of the seizure, unfortunately, did not solve the problem, since EEG during the attack most often reflects only motor artifacts, for the overcoming of which telemetric registration of bioelectric activity is required. Most often paroxysmal dyskinesias should be differentiated not with epilepsy in general, but with epilepsy of frontal lobe origin, which is characterized by the fact that frontal seizures are often not accompanied by epileptic activity on the EEG, proceed without disturbance of consciousness, are characterized by unusual motor manifestations (the so-called "pseudo-pseudo-seizures ", Postural phenomena in an attack, etc.). In most cases, the clinical diagnosis of paroxysmal dyskinesia does not cause much difficulty, but there are observations when a differential diagnosis with epilepsy becomes extremely difficult. However, a similar situation is possible with a differential diagnosis with psychogenic seizures.
Indeed, paroxysmal dyskinesias differ from epilepsy by a number of features, many of which are of fundamental importance. As such features can be listed:
- absence of phases in a fit, characteristic of a typical epileptic attack;
- Conservation of consciousness;
- absence of postictal changes in consciousness and electroencephalogram;
- features of the motor pattern that are not characteristic of epilepsy (for example, alternation from an attack to an attack of left-sided, right-sided and bilateral attacks in the same patient, or the appearance of a cross syndrome);
- the possibility of partial control of violent movements during an attack is more pronounced than with epilepsy;
- the possibility of a very accurate imitation of an attack in paroxysmal dyskinesia;
- absence of EEG changes in the seizure in most cases;
- the reaction to sleep deprivation (electroencephalographic and clinical) is directly opposite with paroxysmal dyskinesia and epilepsy (activation shifts on the EEG in the first case and the increase in hypersynchronization in the second, a decrease in dyskinesia in paroxysmal dyskinesia and provocation of seizures with epilepsy).
Benign paroxysmal tortillollis of infants is observed in the first year of life and is manifested by episodes of tilting or rotating the head in one direction lasting from 1 to 3 days, sometimes with pallor and a picture of distress. This picture is occasionally repeated up to 3-6 times a year. Later on these children the paroxysmal corticollis evolves into "benign paroxysmal dizziness" or migraine. In a family history, migraines usually occur.
Alternating hemiplegia in children begins at the age of 3 months to 3 years and is manifested by repeated attacks of hemiplegia with an alternating side of paralysis. The duration of the attack is from several minutes to several days. Other paroxysmal manifestations are also characteristic: dystonia, chorea, which also develop paroxysmally. Bilateral hemiplegia is possible. Characteristic improvement of the state during sleep (hemiplegia disappears during sleep and returns again in wakefulness). The first attacks can be either hemiplegic, or dystonic, or combining both types of seizures. Attacks are often accompanied by nystagmus. These children are also characterized by a delay in mental development. It is possible to attach spasticity, pseudobulbar syndrome and cerebellar ataxia.
Psychogenic (conversion, hysterical) seizures
In typical cases, pseudo-seizures are characterized by an emotionally initiated occurrence with a provoking situation or event, a bizarre pattern of "convulsions". Diagnosis is facilitated by the presence of elements of a hysterical arc in an attack (tilting of the head or chest lift, characteristic tremors of the pelvis, etc.). In a hysterical fit, there may be moaning, crying, tears, laughter (sometimes these phenomena are observed simultaneously), screaming, pseudo-writing and other more complicated vocalizations and dyslalia. Psychogenic seizure is always characterized by a bright vegetative accompaniment with tachycardia, an increase in blood pressure, symptoms of hyperventilation, less often - apnea lasting up to 1-2 minutes, and other autonomic symptoms.
The most reliable differences between psychogenic seizures from epileptic ones are a deviation from the standard model of the motor pattern of the epileptic attack, absence of epileptic activity on the EEG in the attack, absence of slowing of the rhythms in the post-obstructive EEG, absence of a connection between the frequency of seizures and the concentration of anticonvulsants in the blood plasma. As a rule, positive criteria for the diagnosis of psychogenic disorder are revealed and the so-called polysymptomatic form of hysteria takes place.
In addition, with the suspicion of epilepsy, the search for other clinical and electroencephalographic evidences of epilepsy is important: provocation of epileptic activity by 5-minute hyperventilation, sleep deprivation with subsequent EEG recording, a polygraphic recording of night sleep (the most reliable method), video recording of a seizure with the purpose of a detailed analysis of the motor manifestations of an attack. It is always useful to remember that for an unmistakable recognition of the nature of an attack, it is necessary to take into account all the components of the seizure, the interictal period and the disease as a whole. For clinical diagnosis the most informative are the motor manifestations of a seizure.
Convulsive fainting sometimes occurs in patients who are prone to develop syncope. The appearance of convulsions during fainting testifies to the depth and duration of loss of consciousness. In such cases, there may be a significant similarity between fainting and epilepsy: loss of consciousness, dilated pupils, tonic and clonic convulsions, excessive salivation, urinary incontinence and even feces, post-fading weakness sometimes with vomiting and subsequent sleep.
Fainting differs from epilepsy by the presence of a pre-fainting (lipotymic) condition in the form of sensations of nausea, ringing in the ears, premonitions of imminent falling and loss of consciousness. There are vasodepressor (vasovagal, vasomotor); hyperventilation syncope; fainting associated with hypersensitivity of the carotid sinus (GKS syndrome); cough syncope; nicturous, hypoglycemic, orthostatic and some other types of fainting. In all these cases, the patient before the loss of consciousness experiences a feeling of faintness, speaks of dizziness and a premonition of loss of consciousness. Fainting is extremely rare in the horizontal position and never comes in a dream (at the same time they are possible when getting out of bed at night). In any variants of orthostatic hypotension and fainting, the patient complains of non-systemic dizziness and general weakness. In the diagnosis of syncope, it is important to consider the orthostatic factor in their genesis. Patients suffering from fainting often show a tendency to arterial hypotension. To clarify the nature of syncope, a cardiac examination is also necessary to exclude the cardiogenic nature of syncope. A certain diagnostic value is Ashner's test, as well as such techniques as compression of the carotid sinus, Valsalva test, 30-minute standing with periodic measurement of blood pressure and heart rate, cardiac tests for diagnosis of peripheral vegetative failure.
Convulsions in generalized tonic-clonic epileptic seizures differ somewhat from seizures with fainting. With fainting, they are often confined to isolated twitchings. Muscle spasms with fainting begin with opisthotonus, which has nothing to do with adverse seizures in temporal epilepsy.
Of decisive importance are EEG studies; while nonspecific abnormalities on the EEG do not speak in favor of epilepsy and should not mislead the doctor. Apply all methods of provoking epileptic activity on the EEG.
Acute paroxysm of hyperventilation
The attack of psychogenic hyperventilation leads to the development of respiratory alkalosis with such typical symptoms as mild headache, dizziness, numbness and tingling in the limbs and in the face, visual disturbances, muscle spasms, palpitations, fainting (or epileptic seizure). Such patients often complain of tightness in the chest, inability to take a deep breath. There may be aerofagia, which can lead to abdominal pain. Against the background of dyspnea, there may be the appearance of shivering and oznobopodobnogo hyperkinesia, as well as tetranic convulsions in the extremities. Such patients sometimes make the wrong diagnosis of "diencephalic epilepsy".
Thetania reflects the apparent or latent deficiency of parathyroid glands (hypoparathyroidism) and is manifested by a syndrome of increased neuromuscular excitability. An obvious form is observed with endocrinopathy and occurs with spontaneous tetanic muscle cramps. The latent form is provoked most often by neurogenic hyperventilation (in the picture of permanent or paroxysmal psycho vegetative disorders) and manifested by paresthesias in the limbs and face, as well as selective muscle cramps ("carpopedal spasms", "hand of the obstetrician"). Characteristic emotional and vegetative disorders, as well as other symptoms of psychogenic disease (dissomniac, tsefalgicheskie and others). In severe cases, trismus and spasm of other facial muscles can be observed, as well as involvement of the muscles of the back, diaphragm and even the larynx (laryngospasm). There is a symptom of Khvostek and a symptom of Trusso-Bansdorf and other similar symptoms. A low level of calcium and an elevated phosphorus content in the blood are also characteristic. But there is also normocalcemic tetany. A positive EMG test is detected for latent tetany.
It is necessary to exclude parathyroid gland diseases, autoimmune processes, psychogenic disorders of the nervous system.
Early dyskinesia (acute dystonic reactions) refers to neuroleptic syndromes and manifests more or less generalized dystonic spasms more often in the muscles of the face, tongue, neck, axial musculature: oculogy crisises, blepharospasm, trisus, forced mouth opening, protrusion or twisting attacks, torticollis, crises of opisthotonus, pseudosalamove attacks. About 90% of acute dystonic reactions occur in the first 5 days of therapy with neuroleptics, 50% of all cases in the first 48 hours ("48 hours syndrome." Acute dystonia is more common in young people (more often in men). Holinolitikami or spontaneously disappears after the withdrawal of neuroleptic.Timeral connection of the syndrome with the introduction of neuroleptic makes diagnosis is not very difficult.
Attacks of hemiballism with ischemic infarcts or TIA
Transient hemiballism can be observed in cases of ischemia affecting the subthalamic nucleus and are manifested by a transient attack of large-scale choreic and ballistic movements on the contralateral half of the body ("hemiballism-hemichorea"). Hemiballism often combines with a decrease in muscle tone in the affected limbs. In general, this syndrome is also described when the caudate nucleus, pallid globe, precentral gyrus or thalamic nuclei are affected (ischemic infarcts, tumors, arteriovenous malformations, encephalitis, systemic lupus erythematosus, HIV infection, TBI, demyelination, tuberous sclerosis, hyperglycemia, basal ganglia calcification , as a side symptom of levodopaterapy in Parkinson's disease, as a complication of thalamotomy).
Transient ataxia can sometimes mimic transient hyperkinesis. Such ataxia can be iatrogenic (for example, in treatment with diphenin), in encephalitis in children, as well as in certain hereditary diseases (episodic type I ataxia, type II episodic ataxia, Hartnup disease, maple syrup urine sickness, pyruvate dehydrogenase deficiency). In adults, the causes of periodic ataxia can be drug intoxication, multiple sclerosis, transient ischemic attack, compression lesions in the region of the large occipital opening, intermittent obstruction of the ventricular system.
For differential diagnosis of psychogenic and organic hyperkinesias, a
- positive diagnosis of psychogenic motor disorders and
- Exclusion of organic hyperkinesis.
To address these issues, it is important to consider all the nuances of the clinical picture, and in the hyperkinesia itself, four factors are necessarily assessed: the motor pattern, the dynamics of hyperkinesis, as well as its syndromic environment and the course of the disease.
Formal criteria for the clinical diagnosis of any psychogenic hyperkinesis are the following: a sudden onset with a clear provocative event; multiple motor disorders; Variable and contradictory motor manifestations, fluctuating during one inspection; motor manifestations do not correspond to known organic syndromology; movements increase or become more noticeable when the examination is focused on the affected part of the body and, on the contrary, the movements decrease or stop when attention is distracted; hyperexclusion or excessive starter reactions; pathological movements (hyperkinesis) respond to placebo or suggestion, associated pseudosymptoms are identified; motor disorders are eliminated by psychotherapy or discontinued when the patient does not suspect that they are watching him. To each individual psychogenic hyperkinetic syndrome (tremor, dystonia, myoclonus, etc.), there are some additional specifying diagnostic nuances on which we do not dwell here.
As differential diagnostic criteria, such features of hyperkinesis as changing its expression under the influence of emotional stimuli, a change in the level of wakefulness, hypnotic suggestion, amytal-sodium disinhibition, alcohol intake, changes in body posture or its parts, fluctuations in the severity of hyperkinesis in the form of "Bad" and "good" days.
In addition, some phenomena related to sleep can also be included in "episodes of violent movements": benign night myoclonus (in infants), yaktion ("swings"), restless legs syndrome, periodic limb movements during sleep (and other similar syndromes). Close to the behavior in the syndrome of nightly fears, somnambulism.
Some variants of stereotypy (and, possibly, affective-respiratory seizures) may also be included in this group.