He West syndrome (SW) Is an age-dependent type of childhood epilepsy (Arce-Portillo et al., 2011). It is an epileptic encephalopathy characterized by a symptomatic triad: infantile spasms, hypsarrhythmia and delayed psychomotor development.
In addition, it is also common to find other names in this pathology, such as"Infantile Spasms"or"Infantile Spasms", in the Anglo-Saxon medical literature (Asociación Andaluza de Epilepsia, 2016).
Generally, the typical development of the clinical picture of West syndrome occurs around 4-8 months of age (National Institute of Neurological Disorders and Stroke, 2015).
Both incidence and prevalence vary significantly depending on the geographical area, however, different statistical studies have shown a greater occurrence in males (Arce-Portillo et al., 2011).
West syndrome can be classified into several forms depending on the underlying etiologic cause (symptomatic, secondary, cryptogenic and idiopathic); however, the most frequent are related to prenatal events (Guillén Pinto and Guillén Mendoza, 2015).
Although there is no treatment for West syndrome, therapeutic intervention with Adrenocorticotropic hormone (ACTH) and Vigabatrin (VGB), tend to evolve favorably (Guillén Pinto and Guillén Mendoza, 2015).
Characteristics of West syndrome
West syndrome (SW) is an age-dependent type of childhood epilepsy that is associated with three classic symptoms: infantile spasms, hypsarrhythmia, and a generalized delay in psychomotor development (Arce-Portillo et al., 2011).
The epilepsy Is a neurological disorder that is characterized by the development of recurrent episodes of unusual neuronal activity, called seizures or seizures (Fernández-Suárez, et al., 2015, Mayo Clinic, 2015).
Besides, the epilepsy Is one of the most frequent chronic neurological diseases in the general population (Medina, 2015). Around 50 million people suffer from epilepsy worldwide (World Health Organization, 2016).
In the case of the child population, one of the most serious and common forms of epilepsy is West syndrome (SW), a type of epileptic encephalopathy (Medina, 2015).
The term Encephalopathy Is used to name different brain pathologies that alter both its structure and its efficient functioning (National Institute of Neurological Disorders and Stroke, 2010). In the case of epileptic encephalopathy, neurological alterations will include: abnormal cerebral activity, seizures, cognitive and behavioral deficits, among others (Epilepsy Foundation, 2008).
West's syndrome was first described in 1841 by William J. West through the case of his 4-month-old son (Guillén Pinto and Guillén Mendoza, 2015).
William J. West, pointed out the rare and unique seizures peculiar to the child population that occurred within this medical condition.
Later, some authors such as Lennox and Davis, or Vasquez and Turner (1951), accurately described the characteristic symptoms of West's syndrome, then referred to as" Little Bad Variant "(Andalusian Association of Epilepsy, 2016).
Over time, different denominations have been used, such as"infantile spasms"or"epileptic spasms"; however, the term"West syndrome"performs the most appropriate etiological, clinical, and historical grouping (Andalusian Association of Epilepsy, 2016).
About us
West syndrome presents a frequency of around 2-10% of all diagnosed cases of childhood epilepsy; it is the most frequent form of epilepsy during the first year of life (Arce-Portillo et al., 2011).
The incidence has been estimated in approximately 1 case per 4,000 children, while the characteristic age of onset is between 4 and 10 months (Arce-Portillo et al., 2011).
As for sex, some statistical studies have shown that males are slightly more affected by West syndrome (Andalusian Epilepsy Association, 2016).
Signs and symptoms
West syndrome (SW) is associated with a classic triad of symptoms: infantile spasms, hypsarrhythmic cerebral electrical tracing, and a significant delay or arrest of psychomotor development (Arce-Portillo et al., 2011).
Childhood spasms
Infantile spasms constitute a type of seizure that appears in different infantile epileptic syndromes. They usually appear in very early stages of life, between 4 and 8 months of age (National Institute of Neurological Disorders and Stroke, 2015).
These types of seizures are miclonic (strong and sudden jerks in the arms and legs) and can occur in groups of up to 100 episodes (Guillén Pinto and Guillén Mendoza, 2015).
Specifically, infantile spasms are characterized by a flexion of the body forward, accompanied by rigidity in the extremities (arms and legs). In addition, many children have to arch the lower back as they extend arms and legs (National Institute of Neurological Disorders and Stroke, 2015).
These muscle spasms are the result of an abnormal electric shock at the brain level, they usually start abruptly and can last from seconds to minutes, between 10 and 20 (National Organization for Rare Disorders, 2015).
Generally, infantile spasms have to appear in the early hours of the day (on awakening) or after a meal (National Institute of Neurological Disorders and Stroke, 2015).
In addition, it is also possible that muscle spasms are accompanied by other events such as (Discapnet-Fundacion ONCE-, 2009):
- Alteration of respiratory function.
- Screams or facial flushing.
- Abnormal or altered eye movements.
- Smiles or involuntary smiles.
Hipsarrhythmia
Studies of brain activity through Electroencephalography (EGG), has shown that children with West syndrome have an abnormal and chaotic brain electrical pattern, called hypsarrhythmia (Syndrome.info, 2016).
The University of Navarra Clinic (2015) defines hypsarrhythmia as an electroencephalographic pattern that is characterized by persistent slow wave, tip, acute wave and absence of hemispheric synchronization, giving the sensation of an absolute disorder of brain electrical activity To observe the electroencephalogram .
Psychomotor development
West syndrome can lead to both an absence and a delay in child psychomotor development.
Therefore, affected children may show a significant delay in acquiring the skills required for muscle coordination and control of voluntary movements (National Organization for Rare Disorders, 2015).
In addition, it is also possible that the affectation of this area is manifested as a regression of these abilities. It is possible to observe that the affected child stops smiling, holding his head, sitting down, etc. (Andalusian Association of Epilepsy, 2016).
The loss of previously acquired skills and Neurological disorders , May lead to the development of various medical conditions such as (Discapnet-Fundacion ONCE-, 2009):
- Diplegia : Paralysis in both parts of the body.
- Quadruple or quadriplegia : Paralysis of the four limbs.
- Hemiparesis : Weakness or light paralysis of one of the body halves.
- Microcephaly : The cranial perimeter and head of a baby or child is smaller in size compared to their age group and
sex.
Causes
Depending on the identification of the condition or event that gives rise to West syndrome, it is possible to classify it as symptomatic and cryptogenic (Arce-Portillo et al., 2011).
Symptomatic or secondary West syndrome
With the secondary or symptomatic term refers to those cases of West syndrome in which the clinical characteristics are the product of different detectable brain alterations (Pozo Alonso, et al., 2002).
In this group of cases, it is possible to distinguish between prenatal, perinatal and postnatal causes, depending on when brain damage occurs (Pozo Alonso, et al., 2002).
- Prenatal (Before birth): Cerebral dysplasia, tuberous sclerosis, chromosomal anomalies, infections, metabolic diseases, congenital syndromes or hypoxic-ischemic episodes are among the most common.
- Perinatal (during birth) : Hypoxic-ischemic encephalopathy and hypoglycemia are the most frequent etiologic causes during birth.
- Postnatal (after birth) : Among the most common postnatal causes are infections, cerebral haemorrhages, Cranioencephalic trauma , Hypoxic-ischemic encephalopathy and Brain tumors . In addition, we can also classify these causes in: determined brain involvement, encephalopathy and other causes (Andalusian Association of Epilepsy, 2016).
- Specific brain involvement : Product of metabolic diseases - phenylketonuria, hyperglycemia, histidinemia -; Cerebral malformations -microgyria, paquiria, lisencephaly, hiloprosencephalias, agenesis of the corpus callosum; Or phacomatosis.
- Pre-spasm encephalopathy : There are cases in which the affected children present with a previous significant psychomotor delay, neurological signs and epileptic seizures.
- Other causes : Brain injuries, tumors, Stroke , Hypoxia, etc., as Possible etiologic causes of West's syndrome.
West cryptogenic or idiopathic syndrome
With the term cryptogenic or idiopathic we refer to those cases of West syndrome in which the exact cause that gives rise to clinical manifestations is not known precisely or is not identifiable (Pozo Alonso, et al., 2002).
In addition to these classifications of etiological causes, different statistical studies have shown that the most frequent ones are secondary ones (83.8%) and within these, prenatal causes predominate (59.5%), among them sclerosis Tuberous and congenital brain malformations (Guillén Pinto and Guillén Mendoza, 2015).
- Tuberous sclerosis : Is a pathology of genetic origin that is characterized by the appearance or growth of benign tumors (hermatomas) and malformations in different organs - skin, brain, heart, eyes, lungs, kidneys - (Sáinz Hernández and Vallverdú Torón, x).
- Congenital cerebral malformations : Abnormal development of brain structure as a result of disruption complex process of prenatal development.
Diagnosis
The clinical diagnosis of West syndrome is based on the identification of the symptomatological triad: infantile spasms, abnormal cerebral electrical activity and psychomotor retardation.
Therefore, the first step in the detection of these is the making of the medical history, through which the different specialists try to obtain information about the presentation of symptoms, age of onset, individual and family medical history, etc. ...
On the other hand, the use of electroencephalography (National Organization for Rare Disorders, 2015) is frequently used to characterize the individual's brain activity pattern.
Electroencephalography is a noninvasive technique that does not cause pain. It is used to record patterns of brain activity and detect any abnormalities.
When the pattern called hypsarrhythmia is detected, this finding may help determine the diagnosis of West syndrome (National Organization for Rare Disorders, 2015).
In addition, the use of other brain imaging techniques such as Computed tomography (CT) or the magnetic resonance (MRI), are used both to determine the etiologic cause of the disease and to rule out the presence of other neurological disorders (National Organization for Rare Disorders, 2015).
Thus, other laboratory tests such as urine, blood, lumbar puncture, or genetic tests may also be required for differential and etiologic diagnosis (National Organization for Rare Disorders, 2015).
Is there a cure?
There is no cure for West's syndrome. Despite this, some beneficial pharmacological therapies have been identified.
In some cases, it is possible to use anticonvulsive drugs to control or reduce seizure activity, but in others it is not effective (National Organization for Rare Disorders, 2015).
On the other hand, the most common treatment in West's syndrome includes the use of two drugs: vigabatrin (VGT) and treatment with adrenocorticotropic hormone (ACTH) (Arce-Portillo et al., 2011).
Vigabatrin ( VGT )
Although it is a drug that has proven to be effective for the control of epileptic seizures, muscular spasms for children, etc. Its use is very restricted due to the possible side effects (alteration of the visual field, development of behavioral disorders, headache, paresthesia, amnesia, weight gain, essential tremor, diarrhea, etc. (Spanish Society of Neurology- Epilepsy Group- , 2016).
Adrenocorticotropic hormone (ACTH)
Hormone Therapy Adrecorticotropes Were the first to demonstrate their efficacy, however, it presents high toxicity. Some of the complications secondary to this treatment are: mortality (5%), infections, arterial hypertension, cerebral hemorrhages, cardiac alterations, sedation, drowsiness, among others (Discapnet - Fundacion ONCE-, 2009).
What is the forecast?
The future prognosis of children with West syndrome depends to a large extent on the underlying cause and severity (Syndrome.info, 2016).
Many sufferers respond quickly and effectively to treatment, reducing or even relapsing infantile spasms (Syndrome.info, 2016).
Most often, however, crises occur recurrently throughout childhood, including Lennox-Gastaut syndrome (Syndrome.info, 2016).
In general, children affected by West syndrome present a generalized development of learning and motor skills.
References
- Arce-Portillo, E., Rufo-Campos, M., Muñoz-Cabello, B., Blanco-Martínez, B., Madruga-Garrido, M., Ruiz-Del Portal, L., & Candau Ferández-Mensaque, R (2011). West syndrome: etiology, therapeutic options, clinical evolution and prognostic factors. Rev Neurol., 52 (2), 81-89.
- Andalusian Association of Epilepsy. (2016). West Syndrome . Obtained from Apex. Andalusian Association of Epilepsy.
- Clinical University of Navarra. (2015). Hypsarrhythmia . Obtained from Clínica Universidad de Navarra.
- Disability (2009). West Syndrome . Obtained from disability: http://salud.discapnet.es/.
- Epilepsy Foundation. (2008). Epileptic Encephalopathies in Infancy and Childhood . Obtained from Epilepsy Foundation.
- Glauser, T. (2016). Infantile Spasm (West Syndrome) . Obtained from MedsCAPE.
- Guillén-Pinto, D., & Guillén Mendoza, D. (2015). West's syndrome, experience with a series of cases with access to the first-line treatment. Rev Neuropsiquiatr, 78 (2).
- Medina, P. (2015). West syndrome, the challenge of timely care. Rev Neuropsiquiatr, 78 (2).
- NIH. (2010). Encephalopathy . Retrieved from the National Institute of Neurological Disorders and Stroke: http://www.ninds.nih.gov/.
- NIH. (2015). Infantile Spasms . Retrieved from the National Institute of Neurological Disorders and Stroke.
- NORD. (2015). West Syndrome . Retrieved from the National Organization for Rare Disorders.
- SEN. (2016). Vigabatrin . Obtained from SEN Epilepsy Group.
- Sindrome.info. (2016). West Syndrome . Obtained from Sindrome.info.