West syndrome is a complex of manifestations of a rather severe form of epilepsy that occurs in young children and is a consequence of brain damage. The most striking sign of this pathology is a pronounced lag in mental development. Also, it is precisely for this disease that the symptomatic complex is characteristic: involuntary movements in the form of nods and fast tilts of the body, which by their nature are repetitive spastic contractions of individual muscle groups or of a generalized nature. Manifested mainly in the process of falling asleep or on awakening. In this case, electroencephalography captures clear hypsarrhythmia, which is an abnormally high-amplitude activity of the brain.
Description of the disease
The disease usually manifests itself in infancy, most of the manifestations occur in the age of up to a year.
Diagnostic methods are based on the analysis of clinical symptoms, which is further confirmed by the results of computed tomography, magnetic resonance imaging, as well as the results of EEG (electroencephalography). Treatment is carried out with the help of antiepileptic drugs, drugs of the steroid group. Surgical intervention may also be required to remove a portion of the brain in which there is a focus of epi-activity.
A bit of history and statistics
For the first time, West syndrome considered by us was noticed and described by a doctor with the same name in 1841. He observed manifestations in his child and singled them out into a separate symptomatic complex, which was subsequently made into a separate diagnosis. Since this pathology occurs in infancy, the spasmodic and paroxysmal manifestations characteristic of it are called infantile spasms. Initially, this syndrome was not assigned to a separate category of diseases, but was considered its variant of the manifestation of a generalized form of epilepsy.
In the mid-20th century, on the basis of data obtained from the study and analysis of EEG data from small patients, the specificity of the gypsarrhythmic activity of the brain was determined, which is characterized by a chaotic alternation of slow-wave periods with high amplitude commissures. Based on these specific EEG patterns, the disease was identified as a separate diagnostic criterion, which is typical for small patients.
Single syndrome
With the discovery and improvement of neurovisual diagnostic methods, it became possible to detect foci of brain matter affected by epiactivity in children. It is these new approaches and the data obtained on their basis that caused the refusal to consider West syndrome as a generalized form of epilepsy. From that moment on, they began to classify him as epileptic encephalopathy. Thus, this type of epileptic form of encephalopathy was isolated into a separate syndrome for children. For adult patients, it began to be called Lennox-Gastaut syndrome.
According to statistics, the prevalence of this form of epilepsy (West syndrome) among children with fixed brain disorders is about 2%, and among infant epilepsies, the diagnosis is about 25% of all cases. The incidence rate is 2-4 patients per 10,000 newborns. In boys, the disease is detected more often than in girls. In 90% of cases, the syndrome manifests itself up to a year, the peak of the disease occurs at the age of 4 to 6 months. By the age of three, spasmodic symptoms either disappear altogether or flow into other forms of epilepsy.
Angel Children and West Syndrome
There is a community of parents of special children on the Web. In it you can find information about the syndrome we are describing. Moms share their feedback on the symptoms of the disease in their babies, as well as on treatment methods. The site is called "Angel Children". West syndrome is a pathology that raises many questions in the parents of newborns affected by it.
Etiological features
Most cases are symptomatic.
Unfortunately, there is no accurate data on the etiology of the disease. The causes may be acute intrauterine infections (cytomegalovirus, herpetic), hypoxic lesions of the fetus, postnatal encephalitis, premature birth, asphyxia of the newborn, intracranial birth injury, postnatal ischemia, etc.
In addition, it is very likely that West syndrome in children may result from anatomical abnormalities of the brain, such as, for example, corpus callosum, hemimegalencephaly.
Also, infantile cramps can have secondary symptoms, i.e., be a consequence and symptom of other diseases, such as phacomatosis, neurofibromatosis, Down syndrome, some gene mutations. There is also evidence of a relationship between infantile spasms and phenylketonuria.
Causes
In approximately 10% of cases, the cause of the disease cannot be established, but there is a genetic predisposition, since a family history can reveal the presence of such epileptic symptoms.
There are also a number of assumptions about the relationship of the occurrence of pathology with vaccination, namely with DTP vaccination. However, the existence of such a connection is not a proven fact. It is possible that there is a simple coincidence of the vaccination calendar time and age at which the primary signs of West syndrome are most characteristic.
The pathogenetic mechanism of infantile spasms in modern medicine has only hypothetical justifications. According to one point of view, West syndrome is a consequence of dysfunction of serotonergic neurons. The origin of this hypothesis is based on the presence of a low hormone serotonin and its metabolites.
The exact causes of West syndrome are not fully understood.
There is also an immunological rationale that states the relationship between activated B cells and the disease.
Separately, it is worth noting the theory of the dependence of pathology and impaired functioning of the brain and adrenal glands. The basis for this assumption is a positive result of the treatment of West syndrome with ACTH.
Some scientists see the cause of the syndrome in the excessive production of excitatory synapses and conducting collaterals, which cause an increased level of excitability of the cerebral cortex, and physiological deficiency of myelin for infancy causes an asynchronous EEG picture.
As a child grows up and his brain develops, myelin levels increase, which leads to a noticeable decrease in its excitability. Accordingly, the picture of spasmodic manifestations noticeably fades: they either disappear or turn into Lennox-Gastaut pathology.
Consider the main symptoms of West syndrome.
Symptomatic picture
As we noted above, the disease usually manifests itself during the first year of life. There are cases of a later primary manifestation of the syndrome, but a maximum of 4 years.
The main clinical picture is represented by serial muscle cramps and a lag in physical and mental development. In this case, the delay in psychomotor development in most clinical cases has a primary manifestation, and paroxysmal symptoms already appear on its background. However, in 30% of children, a noticeable developmental delay is preceded by the appearance of paroxysm.
Usually a delay in psychomotor development manifests itself in the absence or unmotivated extinction or the complete disappearance of the grasping reflex. There are also cases of a lack of ability to fix the gaze on the subject or to follow it. These symptoms have a rather unfavorable prognosis for further development.
Muscle spasms
It is serial and symmetrical in nature, the time intervals between them are quite short and usually make no more than a minute. Cramps are most intense at the onset of an attack, and in the end they decline. Spasmodic seizures have no predictability, their frequency can vary from one to several tens per day. Their characteristic feature is a rather dense physiological connection to the time of awakening and the time of falling asleep, when the child is between the stage of sleep and wakefulness. They can provoke a loud sound, a sudden unexpected movement and even touching.
Flexion and extensor
Depending on which muscle group undergoes involuntary contraction, spasmodic manifestations are classified into flexion and extensor, but most often the spasms are mixed. The flexors follow them in frequency, but the extensor ones are the most rare in frequency of cases. Most often, a child is disturbed by spasms of various types, while the prevailing picture of one of them is observed. It is impossible to predict exactly which spasm will prevail, since it depends on the position in which the child’s body is at the moment of the start of the next spasmodic attack.
Cramps can be localized in nature, which occurs most often, and can be generalized - this means that all muscle groups are contracting.
Let us describe the relationship of contractile activity of different muscle groups with their clinical picture:
- Convulsive flexion of the neck muscles causes head nods, which are one of the hallmarks of West syndrome symptoms.
- Spasmodic contractions of the muscles of the shoulder girdle manifest as shrugs.
- Paroxysm “folding knife” - the result of involuntary flexion of the abdominal muscles.
- Spasmodic contractions of the muscles of the upper extremities look as if the child is hugging himself. The combination of this type of spasm with the previous one (“folding knife”) is called the “Salaam attack”. The combined picture of these two types of spasms resembles oriental greeting and “salaam”.
- If the child already knows how to walk, then cramping can occur as follows: the child goes and suddenly falls, but remains conscious.
- Sometimes convulsive seizures are observed, which manifest themselves in the form of a sharp stop of motor functions.
- Spasmodic attacks of the respiratory system are manifested by a violation of respiratory activity, which is a particularly dangerous symptom.
- There are other types of seizures, they can have both an independent manifestation and occur in combination with others.
Diagnostics
The diagnosis of West syndrome is based on three factors:
- mental retardation;
- hypsarrhythmic picture of the EEG pattern;
- muscle spasms.
Of great importance is the age at which the disease begins to manifest itself, as well as the relationship of cramping with sleep. In the case when the disease manifests itself at an uncharacteristically late age, difficulties with diagnosis may occur.
If West syndrome is suspected, the child is consulted by a neurologist, followed by further examination by a geneticist and epileptologist. Important is the timely differentiation of diseases such as benign infant myoclonus, infant myoclonic epilepsy, Sandifer syndrome, in which the head tilts like torticollis are pronounced, as well as episodic manifestations of opistotonus, which resemble spasmodic contractions, but, in fact, they are not.
EEG
EEG (interictal) is done both in a dream and during wakefulness. It shows chaotic, dynamically changing spike-wave activity in both cases. EEG during sleep (polysomnography) records the absence of this activity during deep sleep. At an early stage of the disease, in approximately 66% of clinical cases, EEG shows hypsarrhythmia. At later stages, the EEG patterns have a chaotic organization, and at about 2-4 years old, the EEG is already represented by complexes of alternations of the acute and slow waves. EEG during spasms has a picture of generalized slow-wave high-amplitude complexes and the subsequent extinction of activity.
If the EEG fixes focal changes, it is generally accepted that there is a focal lesion of the brain or it has some structural anomalies.
The most accurate method for diagnosing focal brain lesions is MRI.
Treatment
The real breakthrough in the treatment of West syndrome in children was the use of ACTH (adrenocorticotropic hormone) drugs for the relief of epipristes. The use of ACTH in combination with prednisone leads to a reduction and even complete disappearance of muscle cramps. In turn, the EEG pattern confirms the absence of hypsarrhythmic characteristics. The only stumbling block in the treatment of West syndrome is that the selection of doses and the duration of the course of treatment with these drugs is a purely individual factor and is carried out empirically. In 90% of cases, the use of significant dosages of drugs gives a good effect.
In the early 90s of the 20th century, a positive effect of treatment with vigabatrin was discovered, but the advantage of this drug was proven only for patients with tuberous sclerosis. For the remaining category of patients, steroid therapy remained in the first place. However, the disadvantage of steroid therapy is the worst tolerance to drugs and the tendency of the disease to relapse.
Anticonvulsants
Anticonvulsants are also used for treatment, among which Nitrazepam and valproic acid are the most clinically effective . Some patients came to the positive dynamics of treatment during therapy with large doses of vitamin B6.
In the case of hardware confirmation of the lesion of the foci of the brain and the absence of positive dynamics of stopping the attacks with medications, neurosurgical intervention can be recommended to remove the lesion, which is a catalyst of epiprotic. In the absence of the possibility of such an operation and provided that the patient has a tendency to muscle spasms with a complete loss of motor activity (drop attacks), callosotomy may be necessary.
With West syndrome, is there a cure? We will talk about this later.
Predictive Criteria
With West syndrome, in children up to a year in about half the cases, infantile spasms regress and completely disappear by three years. However, in the remaining 50-60% of cases, an unfavorable continuation of the course of the disease is observed, followed by a transition to other epileptic forms. The most likely transition to Lennox-Gastaut syndrome. If infantile cramps occur against the background of Down syndrome, medication is usually ineffective.
However, it is worth remembering that even in the case of complete disappearance of spasmodic symptoms, the question remains of the psychomotor development of the child, which, as we recall, is an integral factor of West syndrome. Unfortunately, the prognosis of the further course of the disease, even in the absence of paroxysmal manifestations, is disappointing. This applies to lag in mental and physical development, which subsequently manifests itself in the form of cerebral palsy, and in the form of autistic disorders, and in the lag of cognitive-emotional development in general. Approximately 70-80% of children suffer from mental retardation, and half of patients suffer from a delay in physical development. And only a small percentage of the lucky have no serious consequences for further development and growth.
In the event that the disease is a consequence of anatomical structural defects and pathological changes in the brain that are not subject to diagnosis and subsequent surgical correction, the prognosis is even more unfavorable, including in terms of probable mortality.
If there is an idiopathic version of West syndrome, that is, when the appearance of spasms was not preceded by any symptoms of a delay in psychomotor development, the prognosis is much more favorable. The percentage of children with no residual psychomotor deficit is much higher and reaches 37-44%.
West syndrome reviews
Reviews about this disease are contradictory. The timeliness of the diagnosis and treatment of West syndrome is also of great importance. The sooner an ailment is detected and therapy begins, the higher the likelihood of the most favorable prognosis for further mental and physical development of children. Neurologists argue that all brain pathologies and delays in psychomotor development are most effectively amenable to correction in early infancy. The older the child, the less likely it is to have favorable consequences for its development.