AUTHOR AND EDITOR INFORMATION

Section 1 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

INTRODUCTION

Section 2 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Background

West syndrome is composed of the triad of infantile spasms, an interictal EEG pattern termed hypsarrhythmia, and mental retardation, although the diagnosis can be made even if one of the 3 elements is missing (according to the international classification). This severe epilepsy syndrome is an age-dependent expression of a damaged brain. The term "infantile spasms" has been used to describe the seizure type, the epilepsy syndrome, or both. In this article, the term "infantile spasms" is synonymous with West syndrome.

The syndrome's namesake, Dr W J West, gave the first detailed description of infantile spasms, as they occurred in his child. In a letter to the editor of The Lancet in 1841, West described the events as "bobbings" that "cause a complete heaving of the head forward towards his knees, and then immediately relaxing into the upright position … these bowings and relaxings would be repeated alternately at intervals of a few seconds, and repeated from 10 to 20 or more times at each attack, which attack would not continue more than 2 or 3 minutes; he sometimes has 2, 3 or more attacks in the day."

This detailed clinical description was followed approximately 100 years later by the report of the typical interictal EEG pattern termed hypsarrhythmia. Most patients with infantile spasms have some degree of developmental retardation.

The eponym West syndrome was created in the early 1960s by Drs. Gastaut, Poirier, and Pampiglione.

Pathophysiology

Infantile spasms are believed to reflect abnormal interactions between the cortex and brainstem structures. Focal lesions early in life may secondarily affect other sites in the brain, and hypsarrhythmia may represent this abnormal activity arising from multiple brain sites. The frequent onset of infantile spasms in infancy suggests that an immature central nervous system may be important in the pathogenesis. The brain-adrenal axis also may be involved. One theory states that the effect of different stressors in the immature brain produces an abnormal excessive secretion of corticotropin-releasing hormone, causing spasms. The clinical response to adrenocorticotropic hormone (ACTH) and glucocorticoids can be explained by suppression of corticotropin-releasing hormone (CRH) production.

Frequency

United States

Infantile spasm constitutes 2% of childhood epilepsies but 25% of epilepsy with onset in the first year of life. The rate of infantile spasm is estimated between 2.5 to 6.0 per 10,000 live births. Its prevalence rate is 1.5-2.0 per 10,000 children aged 10 years or younger.

International

Infantile spasm occurs in 0.05 (Estonia) to 0.41 (Oulu, Finland) of 1000 live births and in 1.4% (Estonia), 4.2% (Odense, Denmark), and 7.6% (Tampere, Finland) of children with epilepsy.

Mortality/Morbidity

The premature death rate ranges from 5-31%. The upper limit comes from a study of 214 Finnish children with a history of infantile spasms who were followed for a mean of 25 years (range, 20-30 y). Most of the deaths (61%) occurred at or before age 10 years, while only 10% occurred after age 20 years.

Sex

Although males are affected slightly more often than females, no significant gender difference is noted.

Age

Ninety percent of infantile spasms begin in those younger than 12 months. Peak onset is at age 4-6 months.

CLINICAL

Section 3 of 11  

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• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

History

• Ictal manifestations
• • Spasms begin with a sudden, rapid, tonic contraction of trunk and limb musculature that gradually relaxes over 0.5-2 seconds.
    • Contractions can last 5-10 seconds.
    • The intensity may vary from a subtle head nodding to a powerful contraction of the body.
    • Infantile spasms usually occur in clusters, often several dozens, separated by 5-30 seconds.
    • Spasms frequently occur just before sleep or upon awakening. They can be observed during sleep, although this is rare.
  • Spasms can be flexor, extensor, or a mixture of flexion and extension.
    • Flexor spasms consist of brief contractions of the flexor muscles of the neck, trunks, and limbs, resulting in a brief jerk. They may resemble a self-hugging motion and often are associated with a cry. The patient then relaxes, and the jerk repeats. These attacks occur in clusters throughout the day and last anywhere from less than 1 minute to 10-15 minutes or longer in some patients.
    • Extensor spasms consist of contractions of the extensor musculature with sudden extension of the neck and trunk with extension and abduction of the limbs. Extensor spasms and asymmetric or unilateral spasms often are associated with symptomatic cases.
    • Mixed spasms are the most common type, consisting of flexion of the neck and arms with extension of the legs, or flexion of the legs with extension of the arms.
    • In different series the frequency of the 3 spasm types were 42-50% mixed, 34-42% flexor, and 19-23% extensor.
• Interictal manifestations: An arrest or regression in psychomotor development accompanies the onset of spasms in 70-95% of patients.
• Family history: A family history of infantile spasms is uncommon but as many as 17% of patients may have a family history of any epilepsy.

Physical

• General physical examination
• • Physical examination can be important in helping to identify specific etiologies that may have both systemic and neurological symptoms (eg, tuberous sclerosis complex).
  • Often a patient with infantile spasms has normal findings on general physical examination. No pathognomonic physical findings are present in patients with infantile spasms.
  • If abnormalities in the general physical examination are noted (eg, adenoma sebaceum, ash leaf macules), specific etiologies may be suggested.
  • Use a Wood lamp to examine the skin.
  • Patients may exhibit moderate-to-severe growth delay; this is a nonspecific finding and more a reflection of the underlying brain injury than of a specific epilepsy syndrome.
• Neurologic examination
• • The neurologic examination in patients with infantile spasms demonstrates abnormalities in mental status function, specifically deficits in cognitive function consistent with developmental delay or regression.
  • Abnormalities in level of consciousness, cranial nerve function, and motor/sensory/reflex examination are nonspecific findings and more a reflection of the underlying brain injury or effect of anticonvulsant medications than of the syndrome.
  • No pathognomonic findings are present on neurologic examination in patients with infantile spasms.

Causes

Infantile spasms (West syndrome) can be classified according to its suspected etiology as symptomatic, cryptogenic, or idiopathic.

• Symptomatic
• • Patients are diagnosed with symptomatic infantile spasms if an identifiable factor is responsible for the syndrome. Virtually any disorder that can produce brain damage can be associated with infantile spasms.
  • The list of etiologies can be subdivided into prenatal disorders, perinatal disorders, and postnatal disorders.
    • Prenatal disorders include hydrocephalus, microcephaly, hydranencephaly, schizencephaly, polymicrogyria, Sturge-Weber syndrome, incontinentia pigmenti, tuberous sclerosis, trisomy 21, hypoxic-ischemic encephalopathies, congenital infections, and trauma.
    • Perinatal disorders include hypoxic-ischemic encephalopathies, meningitis, encephalitis, trauma, and intracranial hemorrhages.
    • Postnatal disorders include pyridoxine dependency, nonketotic hyperglycinemia, maple syrup urine disease, phenylketonuria, mitochondrial encephalopathies, meningitis, encephalitis, degenerative diseases, biotinidase deficiency, and trauma.
  • Evaluating children with infantile spasms for possible tuberous sclerosis is critical, as this is the single most common disorder, comprising 10-30% of prenatal cases. Tuberosis sclerosis is an autosomally dominant inherited disease with variable manifestations including cardiac tumors, kidney tumors, cutaneous malformations such as ash-leaf hypopigmented lesions, and seizures. In more than a few patients, the family diagnosis of tuberous sclerosis is found only after a child presents with infantile spasms, and an extensive workup of the child and subsequently the family reveals the genetic disease.
  • Of patients with infantile spasms, 70-75% have symptomatic epilepsy. This percentage depends on the degree of sophistication of diagnostic studies. Development of more exquisite neurodiagnostic techniques will alter the relative proportion of symptomatic, cryptogenic, and idiopathic cases.
• Cryptogenic
• • Patients have cryptogenic infantile spasms if no cause is identified but a cause is suspected and the epilepsy is presumed to be symptomatic.
  • The proportion of cryptogenic cases varies from 8-42%. This wide range may be related to variations in the definition of the term "cryptogenic" and the age of diagnosis, since assessment of developmental level in early infancy is difficult.
• Idiopathic
• • Patients may be considered to have idiopathic infantile spasms if normal psychomotor development occurs prior to the onset of symptoms, no underlying disorders or definite presumptive causes are present, and no neurological or neuroradiological abnormalities exist. Some investigators use the terms "idiopathic" and "cryptogenic" interchangeably.
  • The percentage of idiopathic cases reportedly is 9-14%.
• Family history: A family history of infantile spasms is uncommon but as many as 17% of patients may have a family history of any epilepsy.

DIFFERENTIALS

Section 4 of 11  

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• Differentials
• Workup
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• Follow-up
• Miscellaneous
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Other Problems to be Considered

Benign myoclonus of early infancy
Myoclonic-astatic epilepsy

WORKUP

Section 5 of 11  

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• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Lab Studies

• Prior to initiating therapy, consider obtaining some or all of the following laboratory studies:
• • Complete blood count with differential, liver panel, renal panel with electrolytes and glucose, calcium, magnesium, phosphorus, and urinalysis with microscopic examination
  • Metabolic workup including glucose, liver panel, serum lactate and pyruvate, plasma ammonia, serum and urine amino acids, urine organic acids, and serum biotinidase
  • Blood, urine, and cerebrospinal fluid cultures if an infection is suspected
  • Cerebrospinal fluid analysis for cell count, glucose, protein, bacterial and viral culture, lactate, pyruvate, and amino acids

Imaging Studies

• Overview
• • About 70-80% of patients have abnormal findings on neuroimaging studies.
  • Magnetic resonance imaging (MRI) of the brain provides a more detailed evaluation than does a computed tomography (CT) scan of the brain.
  • Imaging studies should be obtained prior to starting ACTH or steroid therapy, as these therapies are associated with the appearance of apparent brain atrophy as treatment continues.
• CT scan
• • Structural brain anomalies such as hydrocephalus, hydranencephaly, schizencephaly, and agenesis of corpus callosum can be recognized easily by CT scans.
  • In addition, cerebral calcifications can be observed in patients with tuberous sclerosis or congenital infections.
• MRI: MRI scans are superior to CT scans in detecting areas of cortical dysgenesis, disorders of neuronal migration, or disorders of myelination.

Other Tests

• Electroencephalogram
• • Always perform an EEG in patients with suspected infantile spasms, since the diagnosis depends on the presence of specific EEG findings.
  • If possible, obtain prolonged video-EEG telemetry to record both waking and sleep EEG to assist in confirming a suspected diagnosis. A routine 20-minute EEG may not capture the patient while both awake and asleep and thus may miss specific important EEG findings.
• Interictal electroencephalogram
• • Hypsarrhythmia is the characteristic interictal EEG pattern and consists of chaotic, high- to extremely high-voltage polymorphic delta and theta rhythms with superimposed multifocal spikes and wave discharges (see Image 1). Multiple variations of this pattern are possible, including focal or asymmetric hypsarrhythmia.
  • In one study of 77 patients with infantile spasms, unilateral hypsarrhythmia and asymmetric ictal EEG changes during spasms often occurred together and correlated with focal or asymmetric cerebral lesions on imaging studies. Patients with symmetric hypsarrhythmia and infantile spasms rarely had focal or asymmetric cerebral lesions on imaging studies (most had structural diffuse brain lesions) and overall had better chances for a normal outcome.
  • In a study of 26 patients with infantile spasms, 6 patients (23%) had asymmetric hypsarrhythmia. All 6 had symptomatic infantile spasms and 5 had focal abnormalities on examination or imaging study (4 ipsilateral to the lesion, 1 contralateral). These focal abnormalities may identify a subset of patients with West syndrome who are candidates for focal cortical resections.
• Ictal electroencephalogram
• • Eleven different types of ictal patterns have been identified in patients with West syndrome.
  • In one study, the most common pattern found in 38% of patients with seizures was a high-voltage, frontal dominant, generalized slow-wave transient followed by voltage attenuation, also termed an electrodecremental episode. These electrodecremental episodes were a feature in 71% of the seizures.
  • No close correlation exists between the type of seizure and the EEG pattern.
• Ophthalmic examination: Ophthalmic examination may reveal chorioretinitis from congenital infections, chorioretinal lacunar defects in patients with Aicardi syndrome, or retinal tubers in patients with tuberous sclerosis.
• Wood lamp: Tuberous sclerosis is the single most common recognizable cause of West syndrome. Therefore, a careful examination of the skin for the characteristic hypopigmented lesions of tuberous sclerosis is mandatory. The unaided bedside identification of these lesions may be more difficult in patients with light complexions.

Procedures

• Lumbar puncture
• • In young infants with early onset of West syndrome, consider a lumbar puncture as part of a full sepsis workup to look for signs of meningitis.
  • In older infants in whom no clear signs of infection are present, a lumbar puncture also is useful in evaluating metabolic causes of West syndrome such as nonketotic hyperglycinemia.

TREATMENT

Section 6 of 11  

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• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Medical Care

• The goals of treatment for infants with West syndrome are the best quality of life with no seizures, the fewest adverse effects from treatment, and the least number of medications.
• Medications such as ACTH and conventional antiepileptic medications (AEDs) are the mainstay of therapy for infants with West syndrome. Unfortunately, no one medical treatment gives satisfactory relief for all infants with West syndrome.
• The various medical treatment options for infants with West syndrome can be divided into 2 major groups:
• • Commonly used first-line treatments (ie, ACTH, prednisone, vigabatrin, pyridoxine [vitamin B-6])
  • Second-line treatments (ie, benzodiazepines, valproic acid, lamotrigine, topiramate, zonisamide)

Surgical Care

• Focal cortical resection: In some patients, resection of a localized region can lead to freedom from seizures.

Consultations

• Pediatric neuropsychologists can assess intellectual function and educational needs and advise on nonpharmacologic management of behavioral problems.
• Pediatric psychiatrists can advise on pharmacologic management of behavioral problems.
• Neurosurgeons can help assess whether the infant is a candidate for focal resection.
• Dietitians can assist in the institution and maintenance of the ketogenic diet.

Diet

• The ketogenic diet has been employed successfully to treat a variety of seizure types. However, the role of the ketogenic diet in the treatment of infants with West syndrome is not defined.

MEDICATION

Section 7 of 11  

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The goals of treatment for infants with West syndrome are the best quality of life with no seizures, the fewest adverse effects from treatment, and the least number of medications.

Drug Category: Hormonal agents

These agents cause profound and varied metabolic effects. Corticosteroids modify the body's immune response to diverse stimuli.

Drug Name	Prednisone (Deltasone, Orasone, Meticorten)
Description	A 2004 American Academy of Neurology and Child Neurology Society practice parameter concluded that "there is insufficient evidence that oral corticosteroids are effective in the treatment of infantile spasms (Level U)." Few comparative studies between ACTH and prednisone have been performed; one double-blind, placebo-controlled, crossover study demonstrated no difference between low-dose ACTH (20-30 U/d) and prednisone (2 mg/kg/d), while second prospective, randomized, single-blinded study demonstrated high-dose ACTH at 150 U/m2/d was superior to prednisone (2 mg/kg/d) in suppressing clinical spasms and hypsarrhythmic EEG in infants with infantile spasms. A 2004 multicenter, randomized, controlled trial in the UK compared hormonal therapy (either oral prednisolone or intramuscular tetracosactide depot, a synthetic analogue of ACTH) to vigabatrin in 107 infants with infantile spasms. More infants assigned hormonal treatments (73%) had no spasms on days 13 and 14 compared to infants assigned vigabatrin (54%, p=0.043). A follow-up study demonstrated that, although hormone treatment controlled spasms better than vigabatrin initially, by age 12-14 months, both groups had similar seizure-free rates.
Pediatric Dose	2 mg/kg/d PO for 2-4 wk
Contraindications	Documented hypersensitivity; viral infection; peptic ulcer disease; hepatic dysfunction; connective tissue infections; fungal or tubercular skin infections; GI disease
Interactions	Barbiturates, phenytoin, rifabutin, and rifampin can increase metabolism of prednisone; hyperthyroidism can increase metabolism of prednisone; hypothyroidism can decrease metabolism of prednisone; isoproterenol in patients with asthma can increase risk of cardiac toxicity, clinical deterioration, myocardial infarction, congestive heart failure, and death
Pregnancy	B - Usually safe but benefits must outweigh the risks.
Precautions	Prolonged therapy can affect metabolic, GI, neurologic/behavioral, dermatologic, and endocrine systems; metabolic adverse events can include (but are not limited to) fluid retention and electrolyte disturbances (eg, hypernatremia, hypokalemia, hypokalemic metabolic alkalosis, hypocalcemia), edema, hypertension, and hyperglycemia GI adverse events can include nausea, vomiting, abdominal pain, anorexia, diarrhea, constipation, gastritis, esophageal ulceration, weight loss, and delayed growth Neurological and behavioral adverse events reported during prolonged administration can include headache, insomnia, restlessness, mood lability, anxiety, personality changes, and psychosis Visual adverse events may include exophthalmos, retinopathy, posterior subcapsular cataracts, and ocular hypertension Dermatological adverse events reported during therapy can include skin atrophy, diaphoresis, impaired wound healing, facial erythema, hirsutism, ecchymosis, and easy bruising Endocrinological adverse events from prolonged use include hypercorticism and physiologic dependence Idiosyncratic reactions include pancreatitis and dermatological hypersensitivity reactions (allergic dermatitis, angioedema, urticaria); avoid vaccination with live-virus vaccines; avoid abrupt discontinuation if patient has been on long-term therapy Caution in congestive heart failure, hypertension, glaucoma, GI disease, diverticulitis, intestinal anastomosis, hepatic disease, hypoalbuminemia, peptic ulcer disease, renal disease, osteoporosis, diabetes mellitus, hypothyroidism, coagulopathy or thromboembolic disease, or potential impending GI perforation

Drug Category: Anticonvulsants

These agents are used to manage severe muscle spasms.

Drug Category: Benzodiazepines

A 2004 American Academy of Neurology and Child Neurology Society practice parameter concluded that "there is insufficient evidence to recommend benzodiazepines for the treatment of infantile spasms (Level U, Class III and IV evidence)."

By binding to specific receptor sites, these agents appear to potentiate the effects of GABA and facilitate inhibitory GABA neurotransmission and other inhibitory transmitters.

Drug Category: Anticonvulsants

These agents prevent seizure recurrence and terminate clinical and electrical seizure activity.

Drug Name	Lamotrigine (Lamictal)
Description	A 2004 American Academy of Neurology and Child Neurology Society practice parameter concluded that "there is insufficient evidence to recommend lamotrigine for the treatment of infantile spasms (Level U, Class III and IV evidence)." Lamotrigine inhibits release of glutamate and inhibits voltage-sensitive sodium channels, leading to stabilization of neuronal membrane. Effectiveness in West syndrome has been investigated in open-label studies with promising results. Initial dose, maintenance dose, titration intervals, and titration increments depend on concomitant medications.
Pediatric Dose	Combination with AEDs that induce hepatic CYP-450 enzyme system WITHOUT valproate Initial starting dose: 0.6 mg/kg/d PO for 2 wk; 1.2 mg/kg/d for wk 3-4; 5-15 mg/kg/d thereafter; after week 4, dosage increment not to exceed 1.2 mg/kg/d q1-2wk until maintenance dose achieved; maximum daily dose is 400 mg/d Combination WITH valproate with or without other AEDs that induce hepatic CYP-450 enzyme system Initial starting dose: 0.15 mg/kg/d PO for 2 wk; 0.3 mg/kg/d for weeks 3-4; 1-5 mg/kg/d thereafter; after week 4, dosage increment not to exceed 0.3 mg/kg/d q1-2wk until maintenance dose achieved; usual maximum daily dose is 200 mg/d
Contraindications	Documented hypersensitivity; history of erythema multiforme, Stevens-Johnson syndrome, or toxic epidermal necrolysis; erythema multiforme; Stevens-Johnson syndrome; toxic epidermal necrolysis
Interactions	Affected by concomitant AEDs; when used in conjunction with medications that induce hepatic CYP-450 microsomal enzymes (eg, phenobarbital, carbamazepine, phenytoin), clearance enhanced; conversely, when used in conjunction with medications that inhibit hepatic CYP-450 microsomal enzymes (eg, valproate), clearance diminished; lower starting doses, slow titration rate (ie, 2-wk or greater intervals between dosage increases), and smaller increments are needed
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Dose-dependent adverse effects include ataxia, diplopia, dizziness, headache, nausea, and somnolence; idiosyncratic reactions include Stevens-Johnson syndrome and toxic epidermal necrolysis; no long-term (cumulative) adverse effects noted to date Risk factors for associated severe dermatologic reactions include younger age (children more than adults), co-medication with valproic acid, rapid rate of titration, and high starting dose; give careful attention to initial starting dose, titration rate, and co-medications; prompt evaluation of any rash is prudent and imperative; approximately 10-12% of patients develop non–life-threatening rash that usually resolves rapidly upon withdrawal and occasionally without changing dosage

Drug Name	Topiramate (Topamax)
Description	A 2004 American Academy of Neurology and Child Neurology Society practice parameter concluded that "there is insufficient evidence to recommend topiramate for the treatment of infantile spasms (Level U, Class III and IV evidence)." Topiramate is a sulfamate-substituted monosaccharide with broad spectrum of antiepileptic activity that may have state-dependent sodium channel blocking action, potentiates inhibitory activity of neurotransmitter GABA. May block glutamate activity. Effectiveness in West syndrome has been investigated in one open-label study with promising results.
Adult Dose	Initial starting dose: 2-3 mg/kg/d PO; increment of 2-3 mg/kg q3-4d Maintenance dose: 15-20 mg/kg/d PO
Pediatric Dose	Initial starting dose: 2-3 mg/kg/d PO; increment of 2-3 mg/kg q3-4d Maintenance dose: 15-20 mg/kg/d PO
Contraindications	Documented hypersensitivity
Interactions	May increase phenytoin plasma levels; may decrease valproate plasma levels; phenytoin and carbamazepine decrease levels
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Dose-dependent adverse effects include irritability, ataxia, dizziness, fatigue, nausea, somnolence, psychomotor slowing, concentration, constipation, and speech problems; if CNS adverse effects occur, reduce concomitant AEDs, slow titration, or reduce dose; no idiosyncratic reactions noted; oligohidrosis and nephrolithiasis reported

Drug Name	Zonisamide (Zonegran)
Description	A 2004 American Academy of Neurology and Child Neurology Society practice parameter concluded that "there is insufficient evidence to recommend zonisamide for the treatment of infantile spasms (Level U, Class III and IV evidence)." Effectiveness in West syndrome has been investigated in 5 open-label studies with promising results.
Pediatric Dose	Initial dose: 1-2 mg/kg/d PO; increase 1-2 mg/kg/d q2wk Maintenance dose: 8-12 mg/kg/d PO
Contraindications	Documented hypersensitivity
Interactions	Phenytoin, phenobarbital, carbamazepine, and valproate decrease half-life; no effect on steady-state plasma concentrations of other AEDs
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Dose-dependent adverse effects include headache, anorexia, nausea, dizziness, ataxia, paresthesia, difficulty concentrating, irritability, and somnolence; idiosyncratic reactions include severe rash (Stevens-Johnson syndrome, toxic epidermal necrolysis) with reporting rate of 46 per million patient-years of exposure; oligohidrosis and nephrolithiasis reported

Drug Category: Vitamins

These agents are essential for normal metabolic processes.

FOLLOW-UP

Section 8 of 11  

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• Medication
• Follow-up
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Complications

• Complications include dose-related, idiosyncratic, or long-term adverse effects from medications, including death.

Prognosis

• The long-term overall prognosis is poor and is related directly to the etiology.
• • Infants with idiopathic West syndrome have a better prognosis than do infants with symptomatic West syndrome. Only 14% of infants with symptomatic West syndrome have normal or borderline normal cognitive development, compared to 28-50% of infants with idiopathic West syndrome. Mental retardation is severe in 70% of patients, often with psychiatric problems such as autistic features or hyperactivity. Infrequently spasms may persist in adulthood. Fifty to seventy percent of patients develop other seizure types. Eighteen to fifty percent of patients will develop Lennox Gastaut syndrome.
  • Subsets of patients among the symptomatic West syndrome group seem to have a better prognosis. A retrospective study of 17 children with trisomy 21 and infantile spasms found that 13 of 16 survivors were seizure free for more than 1 year and 10 no longer were taking anticonvulsants.
  • A study of 15 children with neurofibromatosis type 1 and infantile spasms also reported a relatively benign seizure and cognitive outcome.
  • Prognosis appears to be worse in infants with other seizure types, persistent EEG abnormalities, poor response to ACTH, and delayed initiation of treatment. One study showed that later onset, normal-to-mild psychomotor delay at the time of diagnosis, and good seizure control were factors related to better prognosis.

MISCELLANEOUS

Section 9 of 11  

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• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Medical/Legal Pitfalls

• Failure to inform the patient's family of the risk for severe adverse effects, including death, from the use of either ACTH or oral steroids
• Failure to inform the patient's family of the risk for severe idiosyncratic reactions from two commonly used antiepileptic medications for West syndrome
• • Valproate - Hepatotoxicity, pancreatitis
  • Lamotrigine - Steven-Johnson syndrome, toxic epidermal necrolysis
• Failure to inform the patient's family of signs and symptoms to watch for that indicate severe adverse effects or idiosyncratic reactions
• Failure to instruct the family on what to do if they notice signs and symptoms indicating severe adverse effects or idiosyncratic reactions
• Failure to fully investigate and identify possible causes of the patient's West syndrome, including identification of tuberous sclerosis (a common cause of West syndrome), which can have implications for the entire family
• Failure to recognize signs and symptoms of West syndrome, which could result in failure to select an appropriate AED with proven efficacy; this could increase the risk for uncontrolled seizures that in turn increase the risk for injury and death

MULTIMEDIA

Section 10 of 11  

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• Follow-up
• Miscellaneous
• Multimedia
• References

Media file 1:  Infantile spasm (West syndrome). Mountainous chaotic disorganized rhythms with superimposed multifocal spikes demonstrating hypsarrhythmia in an 8-month-old boy with infantile spasms and developmental delay. Courtesy of E Wyllie.
	View Full Size Image
Media type:  Rhythm Strip

REFERENCES

Section 11 of 11

• Authors and Editors
• Introduction
• Clinical
• Differentials
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• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

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• Appleton RE, Peters AC, Mumford JP, et al. Randomised, placebo-controlled study of vigabatrin as first-line treatment of infantile spasms. Epilepsia. Nov 1999;40(11):1627-33. [Medline].
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• Commission on Classification and Terminology of the International League Agains. Proposal for revised classification of epilepsies and epileptic syndromes. Commission on Classification and Terminology of the International League Against Epilepsy. Epilepsia. Jul-Aug 1989;30(4):389-99. [Medline].
• Czochanska J, Langner-Tyszka B, Losiowski Z, et al. Children who develop epilepsy in the first year of life: a prospective study. Dev Med Child Neurol. Apr 1994;36(4):345-50. [Medline].
• Debus OM, Kurlemann G. Sulthiame in the primary therapy of West syndrome: a randomized double-blind placebo-controlled add-on trial on baseline pyridoxine medication. Epilepsia. Feb 2004;45(2):103-8. [Medline].
• Donat JF, Lo WD. Asymmetric hypsarrhythmia and infantile spasms in west syndrome. J Child Neurol. Jul 1994;9(3):290-6. [Medline].
• Drury I, Beydoun A, Garofalo EA, et al. Asymmetric hypsarrhythmia: clinical electroencephalographic and radiological findings. Epilepsia. Jan 1995;36(1):41-7. [Medline].
• Eisermann MM, DeLaRaillère A, Dellatolas G. Infantile spasms in Down syndrome--effects of delayed anticonvulsive treatment. Epilepsy Res. Jun-Jul 2003;55(1-2):21-7. [Medline].
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Article Last Updated: Apr 10, 2006