AUTHOR AND EDITOR INFORMATION

Section 1 of 11  

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• 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

Juvenile myoclonic epilepsy (JME) is an idiopathic generalized epileptic syndrome characterized by myoclonic jerks, generalized tonic-clonic seizures (GTCSs), and sometimes absence seizures. JME is relatively common and usually responds well to treatment with appropriate anticonvulsants. However, JME is frequently misdiagnosed until the patient is specifically asked about the leading symptom, jerky movements occurring primarily within the first couple of hours after awakening. Other keys to the diagnosis include normal intelligence, onset around adolescence, GTC seizures occurring shortly after awakening, family history of the condition, and seizures after precipitating factors such as sleep deprivation or psychological stress. Although patients usually require lifelong treatment with anticonvulsants, their overall prognosis is generally good.

Brief history of JME

In 1867, Herpin was the first to describe a probable case of JME.¹ He described a bright boy aged 13 years who developed upper-body jerks that progressed to "full seizures" 3 months later. Later, Rabot², Lundborg³, and other physicians reported patients who had similar seizures, and terms such as impulsions were used to describe the myoclonic jerks. Janz and Mathes published a monograph about patients with "propulsive petit mal epilepsy" in 1955.⁴ In 1957, Janz and Christian published observations of a group of patients with a syndrome now known as JME.⁵ Janz named this syndrome "impulsive petit mal epilepsy." Lund introduced the term juvenile myoclonic epilepsy in 1975⁶, and the International League Against Epilepsy has adopted this term.

Definition

Under the proposal for revised classification of epilepsies and epileptic syndromes, in 1989 the Commission on Classification and Terminology of the International League Against Epilepsy defined JME (impulsive petit mal) as follows: "Impulsive petit mal appears around puberty and is characterized by seizures with bilateral, single or repetitive, arrhythmic, irregular myoclonic jerks, predominantly in the arms. Jerks may cause some patients to fall suddenly. No disturbance of consciousness is noticeable. Often, there are GTCS and, less often infrequent absences. The seizures usually occur shortly after awakening and are often precipitated by sleep deprivation. Interictal and ictal EEG have rapid, generalized, often irregular spike-waves (SW) and polyspike-waves (PSW); there is no close phase correlation between EEG spikes and jerks. Frequently the patients are photosensitive. The disorder may be inherited and sex distribution is equal. Response to appropriate drugs is good." 

In one case of identical twins in the first author's experience (JEC), one twin exclusively had absences and had been treated only with ethosuximide since childhood. She never had myoclonic or generalized tonic-clonic seizures, and her seizures were well controlled with a drug that was considered ineffective in the treatment of these other types of seizures. The other twin first presented with generalized tonic-clonic seizures at the age of 18 years; in retrospect, she had noticed morning myoclonic jerks for 2 years before her presentation. She had never had absences. Their EEGs showed typical polyspike and slow-wave discharges interictally in both cases with no obvious difference between the twins.

Pathophysiology

Etiology

JME is an idiopathic generalized epilepsy syndrome. It is not associated with conditions such as head trauma, brain tumor, or encephalitis. Neuropathologic studies involving specialized staining techniques in patients with primary generalized seizures (including a few with a diagnosis of JME) have revealed microscopic brain alterations. Changes include an increase in the number of partially dystopic neurons in the stratum moleculare, white matter, hippocampus, and cerebellar cortex; an indistinct boundary between the cortex and the subcortical white matter and between lamina 1 and 2; and a columnar arrangement of cortical neurons. These findings are termed microdysgenesia and have been interpreted as a manifestation of minimal developmental disturbances. However, results of routine pathologic analysis of brain specimens from patients with JME are typically normal.

The exact cause of this disorder remains unknown. However, considerable progress has been made in the understanding of some families with specific mutations that yield the clinical phenotype of JME. Some of the known mutations result in abnormalities in ion channel proteins such as the beta-4 subunit of calcium channels and the chloride channel 2 protein. A protein called myoclonin has been identified. Its function remains uncertain but has been implicated in apoptosis, cell division, and cell migration. These functions might explain the subtle abnormalities in cortical migration reported in the neuroimaging of some patients with JME.

Genetics

JME is an inherited disorder, but the exact mode of inheritance is not clear. About a third of patients with JME have a positive family history of epilepsy. About 17-49% of patients with JME have relatives who have epileptic seizures, including parents (about 4%) and children (about 7%). The risk of expressing clinical JME might be slightly higher in female individuals than in male individuals and in relatives of people with JME. However, some studies have shown similar sex-related risks.

Progress in identifying genetic mutations in patients and families with JME has been considerable. Dr. Delgado-Escuet has written a comprehensive review about the genetics of JME.⁷ The syndrome of JME likely consists of many genetic diseases that result in a similar electroclinical syndrome. See Causes for a further discussion on specific mutations.

Although investigators in most studies have presumed that JME is an autosomal dominant condition (ie, 50% risk of inheritance), it has incomplete penetrance, which means that some individuals who inherit the JME gene or genes do not express clinical JME. However, their children may inherit the JME genes and express clinically obvious disease. To an untrained observer, the disease seems to skip generations. For relatives of a patient with JME, the risk of having clinically obvious JME is small: 3.4% in parents, 7% in siblings, and 6.6% in children.

Frequency

United States

The risk of JME in the general population is estimated to be 1 case per 1000-2000 people. JME is a relatively common idiopathic generalized epilepsy. It represents about 5-10% of all epilepsies; however, the exact figures may be higher, as the condition is often misdiagnosed.

International

The incidence and prevalence of JME appear to be the same in all the populations that have been studied.

Mortality/Morbidity

Sudden unexpected death in epilepsy (SUDEP) and accidental morbidity and mortality have been observed as in other epileptic syndromes with generalized tonic clonic seizures. Seizure precautions to minimize these risks are discussed later in this chapter.

Race

No systematic racial differences have been observed. However, it is likely that some specific genetic mutations among the different types described in families with JME might be more prevalent among different racial groups. For example, the myoclonin (EFHC1) mutation has been found in 9-20% of Mexican-American families with JME, but only in 3% of Japanese families with this disorder.⁷

Sex

Findings from some studies suggest that JME is slightly more prevalent among females than males. The reason is unknown. However, data from other studies indicate similar prevalences in both sexes.

Age

• JME typically begins in adolescence. Although the age of onset varies from 6-36 years, symptoms typically begin in adolescents aged 12-18 years.
• Myoclonic jerks, GTCSs, and absence seizures all have an age-related onset in JME.
• If absence seizures are a feature, they usually begin between the ages of 5 years and 16 years. Myoclonic jerks may follow 1-9 years later, usually around the age of 15 years. GTCSs typically appear a few years later than myoclonic jerks.
• Why the onset of this genetic disorder is delayed until adolescence is unclear.

CLINICAL

Section 3 of 11  

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• Clinical
• Differentials
• Workup
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History

JME is diagnosed based on clinical findings. Video EEG monitoring of typical seizures is the criterion standard, but in the great majority of patients, a working diagnosis of probable JME is made on clinical history. Although observers' descriptions of seizures are helpful, caution must be used regarding their validity. The most important element in the diagnosis of JME is the patient's history. Any patient who presents with generalized tonic clonic seizures (GTCSs) without an aura should be questioned about myoclonic jerks, the time of day when the seizures occurred, and any precipitating factors.

• Symptoms usually begin in adolescence.
• Leading symptom is jerky movements that occur in the morning but might occur throughout the day.
• Patients do not lose consciousness during myoclonic jerks.
• Typically, seizures occur shortly after awakening.
• Intelligence is normal.
• Precipitating factors include sleep deprivation and psychological stress.
• About 17-49% of patients have a family history of epilepsy.
• Myoclonic jerks or seizures
• • Myoclonic jerks or seizures without impairment of consciousness are the cardinal symptoms of JME. Although an occasional, strong myoclonic jerk may make patients momentarily seem to be "in a fog," a key feature is that consciousness is preserved during these jerks.
  • The jerks are usually brief, bilateral, arrhythmic contractions that mainly involve the shoulders and arms. However, some patients report jerking in the lower limbs, trunk, or head. Some jerks occur unilaterally.
  • The frequency and intensity of these jerks may vary. For instance, they may be perceived only internally, as an electric shock–like sensation. If the jerks are violent, patients may throw objects they are holding or even fall to the floor.
  • Myoclonic jerks can occur in rapid succession and even progress to myoclonic status epilepticus. However, more often a rapid succession of myoclonic jerks evolves into a primary GTCS.
  • Myoclonic jerks occur as the only seizure type in approximately 17% of patients with JME; the rest have GTCSs, or absence seizures, or both in addition to myoclonic jerks.
• Generalized tonic-clonic seizures
• • GTCSs occur in approximately 80% of patients with JME.
  • GTCSs of JME are typically symmetric, with a prolonged tonic phase that may lead to cyanosis and tongue biting and no sensory aura.
  • GTCSs are sometimes preceded by a series of myoclonic jerks of increasing severity that evolve into an initial clonic phase of a GTCS. The GTCSs often cause a patient with JME to seek medical attention; in this setting, patients should be questioned specifically about myoclonic jerks because most patients do not mention them.
• Absence seizures
• • In JME, absence seizures occur somewhat less often than do GTCSs. Janz reported that 28% of his patients with JME also had absence seizures.
  • When these seizures are a feature of JME, they are often the first clinical manifestation of the syndrome, with myoclonic jerks typically following 1-9 years later. In JME, absence seizures are typically short, lasting a few seconds, and they usually are not accompanied by motor signs.
  • Severity of seizures is somewhat age dependent. When they appear in children younger than 10 years, absence seizures of JME are reported less often than those of childhood absence epilepsy. Some recollection of the ictal events is common, particularly in patients that have persistence of these seizures during adulthood. Automatism is rare. When the seizures begin in children aged 10 years or older, absence seizures of JME may be even less severe than they otherwise would be, with merely a brief interruption in the patient's ability to concentrate.
  • Sometimes, the first manifestations of JME are childhood absence seizures. A clue to this diagnosis is the development of GTCSs or myoclonic seizures within a couple of years after starting treatment with ethosuximide.
  • Approximately 3-8% of children who present with absence seizures ultimately receive a diagnosis of JME.
• Seizure presentations
• • Patients may have myoclonic jerks plus a combination of other seizure types.
  • In about 60% of patients, JME begins with myoclonic jerks, which are followed by the onset of relatively uncommon GTCSs a few years later.
  • The finding of myoclonic jerks plus absence seizures and GTCSs is the next most common combination, occurring in approximately 30% of patients with JME.
  • The combination of myoclonic jerks and absence seizures without GTCSs is rare, occurring in only 2% of patients.
• Precipitating factors of seizures
• • Seizures of JME often are precipitated by lack of sleep, psychological stress, noncompliance of medication, and drinking alcohol. These factors can be a particular problem in adolescents; staying up late at night to study or party can easily lead to myoclonic seizures or GTCS the next morning. Patients with JME tend to be sensitive to photic stimulation. Approximately 30% of patients with JME are photosensitive; females typically are more sensitive than males.
  • The time of day is also important because JME has a characteristic circadian pattern of clinical activity. Myoclonic jerks, GTCSs, and absence seizures all tend to occur in the early morning after the patient awakens. To a lesser extent, these symptoms also occur in the evening when the patient is relaxing. When myoclonic jerks occur in the mornings, patients may have difficulty in eating breakfast or brushing their teeth. In some studies, nearly 90% of patients with JME had myoclonic jerks on awakening; the rest had either random jerks throughout the day or jerks at night.
  • Precipitating factors can be summarized as follows:
  • • Sleep deprivation
    • Psychological stress
    • Alcohol use
    • Noncompliance of medication
    • Photic stimulation
    • Menses
    • Time of day - Usually mornings

Physical

• Findings on physical examination are usually normal. No abnormalities are usually identified in patients with JME.
• Intelligence is normal. This observation is in contrast to findings with diseases such as progressive myoclonic epilepsies, in which progressive mental deterioration is the rule.

Causes

The exact cause of JME remains unknown. Several families have specific mutations in various genes and a complex mode of inheritance.

Mutations in genes encoding ion channels have been associated with JME, including those encoding for the beta-4 calcium channel subunit (CACNB4), the gamma-aminobutyric acid (GABA) receptor subunit (GABRA1), and the chloride channel (CLCN2). Each of these channelopathies have been described in a single family and are rare causes of JME.⁸

One approach has been the use of linkage studies in several families with JME at the same time. This approach led to the identification of 3 additional loci: EJM1 at chromosomal region 6p12-p11, EJM2 at 15q14, and EJM3 at 6p21.

Susuki et al described a gene (EFHC1) in the EJM1 site at 6p12–p11, which had 5 missense mutations that cosegregated with epilepsy or EEG PSW in affected members of 6 unrelated families with JME.⁹ Small, R-type calcium currents were observed with the mutations of EFHC1. Apoptosis, a form of programmed cell death, was also reduced with mutations of EFHC1.

The causative gene at the EJM2 locus has not been identified. The EJM3 locus has been associated with 2 SNP variants of the promoter of the BRD2 (RING3) gene in patients with JME.¹⁰ BRD2 (RING3) is presumed to be a regulator of nuclear transcriptional regulator during development. The mutations found in EJM1 and EJM3 pinpoint genetic factors that are important during development. Therefore, microdysgenetic abnormalities are likely to be found in patients with JME.

DIFFERENTIALS

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Other Problems to be Considered

Epilepsy with generalized tonic-clonic seizures on awakening
Nocturnal generalized tonic-clonic seizures
Myoclonic absence epilepsy
Myoclonus
Partial seizures with secondary generalization
Progressive myoclonic epilepsies

WORKUP

Section 5 of 11  

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• Medication
• Follow-up
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• Multimedia
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Imaging Studies

• Neuroimaging studies are typically normal in JME. Many clinicians believe that, in the presence of an adequate supportive history, EEG abnormalities, normal intelligence, and normal neurologic findings, neuroimaging studies are unnecessary. However, the clinical scenario might not be as clear as the classical description.
• MRIs of the brain are usually unremarkable. This observation reflects the fact that JME is an idiopathic generalized epilepsy and not caused by conditions such as brain tumors or encephalitis.
• Some patients with brain MRIs, particularly if the MRIs are high definition, or high Telsa studies, have shown minor abnormalities of cortical development.

Other Tests

• Study of choice to confirm the clinical diagnosis is sleep-deprived EEG with activation procedures (ie, hyperventilation, photic stimulation). A normal study does not rule out epilepsy or JME. Typical EEG abnormalities are highly supportive of the clinical diagnosis (see Media file 1).
• The typical interictal EEG abnormality consists of a generalized 4- to 6-Hz spike or polyspike and slow-wave discharges lasting 1-20 seconds (see Media file 1). Usually, 1-3 spikes precede each slow wave. When absence seizures are also present, 3-Hz spike-and-wave activity may be seen in addition to the polyspike-and-wave pattern.
• The ictal EEG associated with myoclonic jerks typically reveals 10- to 16-Hz polyspike discharges. These may be preceded by spike and wave activity and are often followed by 1- to 3-Hz slow waves. The number of spikes is typically 5-20 and tends to be proportionately correlated with the clinical intensity of the seizure. These epileptic discharges may briefly persist, even after clinical activity has ceased.
• Absence seizures of JME may be associated with ictal EEG patterns consisting of 3-Hz spike-and-wave activity. Sometimes, these are preceded by 4- to 6-Hz polyspike-and-wave discharges, which slow to 3 Hz as the patient loses consciousness.
• Background activity of the EEG is normal in JME. Hyperventilation and photic stimulation often facilitate the appearance of epileptiform discharges. Photic stimulation frequently precipitates spike-and-wave patterns. This occurs in approximately 30% of patients with JME, compared with 18% of patients with childhood absence epilepsy, 13% of patients with epileptic seizures on awakening, and 7.5% of patients with juvenile absence epilepsy.
• Ictal and interictal polyspike-and-wave discharges are not pathognomonic of JME; they may be seen in other primary generalized epilepsies as well as in myoclonic epilepsies of early childhood.
• In addition to generalized epileptiform discharges, focal abnormalities may be found in 20-55% of patients with JME. These include focal slow waves, generalized discharges that evolve from a focal onset, and focal spikes or spike-and-wave discharges. Ignorance of these changes may lead to one's mistakenly ruling out the syndrome. The etiology of these focal abnormalities is unclear. A possible explanation is structural changes in the cerebral cortex secondary to recurrent seizures or head injury; another is fluctuation in the refractoriness of the cortex to the influence of a spike/wave generator.

TREATMENT

Section 6 of 11  

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Medical Care

Medical therapy with anticonvulsants typically is needed (see Medication). Avoidance of precipitating events such as alcohol use and sleep deprivation may be useful but is not sufficient to control the seizures of JME.

The selection of AEDs for the treatment of JME depends on patient's co-morbidities, preferences, prior history of adverse events, gender, etc. Traditionally, divalproex sodium has been used as first line therapy for JME despite not having an approved FDA indication for this condition. Several studies using Lamotrigine, Topiramate, Levetiracetam and Zonisamide have shown similar efficacy, and in some cases better tolerability than divalproex sodium. In 2006, Levetiracetam became the first drug that received an FDA indication for use specifically in JME.

Surgical Care

Surgical treatment is not indicated, as JME is a primary generalized epilepsy. Some uncontrolled studies have suggested that vagal nerve stimulation might be helpful for patients with intractable seizures of primary generalized onset, such as JME.

Consultations

JME is rarely diagnosed in the primary care setting. Most often, an epileptologist diagnoses the condition after several years of inadequate treatment with medications such as carbamazepine or phenytoin.

Activity

Seizure precautions, including restrictions on driving, must be observed until seizures that impair consciousness are controlled (ie, seizure free) for the recommended period, typically 3-12 months, though the length varies from state to state in the United States. Other precautions include the avoidance of heights, swimming alone, and taking unsupervised baths. Patients with seizures cannot have a commercial driving license until they complete a seizure-free period of 5 years. In addition, patients with seizures are not permitted to fly aircraft.

MEDICATION

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The goal of pharmacotherapy is to reduce morbidity and prevent complications.

The US Food and Drug Administration (FDA) has not approved any anticonvulsant solely for the treatment of JME. In 2006, the FDA approved the adjunctive use of levetiracetam for the treatment of JME. Divalproex sodium has been approved as adjunctive therapy for patients with multiple seizure types that include absence seizures. However, many patients with JME do not have absence seizures. In most patients with JME, seizures are well controlled with monotherapy. Valproic acid has been considered the treatment of choice for JME for many years, but epileptologists are increasingly using other choices as first-line therapies. Approximately 80% of patients with JME become seizure free with valproate monotherapy.

Levetiracetam is useful for the treatment of myoclonic seizures.^{11, 12} It received FDA approval for adjunctive therapy for the treatment of JME in 2006. 

Lamotrigine may also be useful in the treatment of JME. This agent is ideal for patients who cannot tolerate the adverse effects of valproate, such as weight gain, tremor, stomach upset, and hair loss. In some patients, lamotrigine monotherapy has completely controlled their seizures. However, recent evidence indicates that lamotrigine may exacerbate myoclonic jerks. Data from a recent open-label study suggested that lamotrigine was better tolerated than valproate, with similar efficacy.¹³

Topiramate has been useful in the treatment of primary generalized seizures; it may effectively prevent the seizures of JME.¹⁴

Findings from an open-label study also suggested that zonisamide might be effective and well tolerated in patients with JME.¹⁵

In general, low doses of appropriate anticonvulsants are needed to successfully treat JME. Although treatment with phenytoin, carbamazepine, or phenobarbital may control some seizure components of JME (typically at high doses), these drugs may increase seizure frequency (eg, myoclonic exacerbation with carbamazepine) and occasionally precipitate new seizure types, such as absence seizures. However, they may be used in combination if the patient's condition does not respond to other drugs.¹⁶

Clonazepam is often used during seizure exacerbations in patients with JME; however, it is inadequate as long-term treatment.

A patient's medication should rarely changed because he or she is not having seizures. In medical school, physicians are taught to treat patients and not serum concentrations. A low-dose requirement is not unusual; in fact, the great majority of patients with JME need relatively low levels of anticonvulsants to achieve adequate seizure control (as long as it is an appropriate medication for the syndrome). A valproic-acid serum concentration of <20 mcg/mL is certainly a concern, and the patient's spouse or other observer should be interviewed for confirmatory evidence that the patient is not having seizures.

Drug Category: Anticonvulsants

These agents are given to prevent myoclonic, generalized tonic-clonic, and absence seizures.

FOLLOW-UP

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Prognosis

• Seizure control tends to be excellent with relative low doses of the appropriate anticonvulsants (eg, valproic acid).
• • The severity of JME seizures appears to decrease in adulthood and senescence.
  • Whether patients outgrow JME, as compared with other primary generalized epilepsies, at a late age (ie, >60 y) is unknown. However, in one author's experience, older relatives of people with JME who have a history of seizures are often untreated and rarely have seizures. An epidemiologic study is needed to settle this issue.
• Risk of recurrence is more than 80% if anticonvulsants are withdrawn during adolescence or adulthood, even after many years of complete seizure control with low doses of appropriate medications.
• Life-long treatment is usually necessary. However, treating a patient older than 60 years with this condition is rare. Whether JME spontaneously remits after a particular age is uncertain.

Patient Education

• The Epilepsy Foundation has a large selection of brochures and informational booklets for patients and their families. The American Epilepsy Society is the professional organization for people treating patients with epilepsy or for those doing research in this field.
• For excellent patient education resources, visit eMedicine's Brain and Nervous System Center. Also, see eMedicine's patient education article Epilepsy.

MISCELLANEOUS

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Medical/Legal Pitfalls

• The medicolegal pitfalls comprise 2 categories: inappropriate diagnosis and liability of the patients having seizures.
• • One reason for inappropriate diagnosis is that patients often do not report myoclonic jerks. In most patients, JME is diagnosed after they have a generalized tonic-clonic seizure and are treated with one of the usual first-line anticonvulsants, such as phenytoin or carbamazepine. In some cases, carbamazepine increases the frequency of myoclonic seizures, often unmasking the diagnosis. Recognition of worsening with carbamazepine should lead to appropriate diagnosis and therapy. Myoclonic seizures are typically not harmful and rarely associated with any kind of injury.
  • Patients with suspected seizures manifesting as lapses of consciousness during wakefulness should be educated and warned about seizure precautions. Documenting on the patient's chart that driving and occupational hazards for people with seizures were discussed is helpful. Physicians should be aware of state regulations regarding driving, which considerably vary among states and nations.
• Seizure precautions include warnings about unpredictable lapses of consciousness due to seizures during a variety of activities, including the following:
• • Driving vehicles or flying aircraft
  • Immersing oneself in water, eg, for baths, swimming, and other purposes
  • Being at heights, eg, on roofs, scaffolds, and ladders
  • Using fire, eg, on stoves, in ovens, in open fires
  • Using power tools, eg, drills and saws
• Warnings should be tailored to each specific patient, and they should include factors such as seizure control, time of the occurrence of seizures, medication compliance, and the patient's occupation, among other concerns.

Special Concerns

• Most of the time, when a neurologist examines a pregnant woman with epilepsy, it is after the first 6 weeks of gestation (ie, after the neural tube normally closes).
• • That is one of the reasons all women of childbearing age who are taking anticonvulsants should also take folic acid 1 mg/d.
  • In general, most epileptologists believe that the anticonvulsants that help that patient the most should be continued during pregnancy.
  • Frequent monitoring of drug levels is recommended, as pregnancy induces clinically significant changes in drug metabolism, clearance, and volume of distribution.
  • Women with JME are no different than other women who need to take anticonvulsants.
• A great majority of children born to women taking anticonvulsant monotherapy are healthy.
• • Valproic acid and divalproex sodium clearly pose a recognized risk of neural-tube defects (category D) that is higher than the risk associated with older anticonvulsants.
  • Evidence suggests that supplementation with folic acid may decrease this risk.
• Experience is limited with the newer anticonvulsants, including lamotrigine (category C), levetiracetam (category C), and topiramate (category C).
• • Laboratory data indicate some teratogenicity with topiramate, but the effect in humans is unknown.
  • Animal studies have revealed no evidence of teratogenicity related to lamotrigine.
  • Lamotrigine is a weak folic-acid antagonist in the gut; therefore, folic-acid supplementation is required in women of childbearing age taking this drug.

MULTIMEDIA

Section 10 of 11  

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• Differentials
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• Follow-up
• Miscellaneous
• Multimedia
• References

Media file 1:  Findings in a man with a history of generalized tonic-clonic seizures (mostly nocturnal) and myoclonic jerks (mostly in the morning) since the age of 14 years. Carbamazepine exacerbated his myoclonic seizures. Sleep-deprived EEG was digitally recorded and then plotted by using an analog paper machine. The patient was getting drowsy when this burst of polyspike and slow wave was recorded.
	View Full Size Image
Media type:  Photo

REFERENCES

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1. Herpin TH. Des asces incomplets de l'epilepsie. J Balliere et Fils. 1867.
2. Rabot T. De la myoclonia epileptique. Paris, France: Medical thesis; 1899.
3. Lundborg H. Die Progresive Myoklonusepilepsie (Unverricht's Myoklonie). Stockholm, Sweden: Almqvist & Wiksell; 1903.
4. Janz D, Mathes A. Die Propulsiv Petit Mal Epilepsie. New York, NY: Garger; 1955.
5. Janz D, Christian W. Impulsive petit mal. Deutsche Leitschrift f Nervenheilkunde. 1957;176:346-386.
6. Lund M, Reintoft H, Simonsen N. Ein kontrolleret social og psychologisk Undersgelse af Patienter med Juvenil Myoklon Epilepsi. Ugeskr Laeg. 1975;137:2415-18.
7. Delgado-Escueta AV. Advances in genetics of juvenile myoclonic epilepsies. Epilepsy Curr. May-Jun 2007;7(3):61-7. [Medline].
8. Wallace R. Identification of a new JME gene implicates reduced apoptotic neuronal death as a mechanism of epileptogenesis. Epilepsy Curr. Jan-Feb 2005;5(1):11-3. [Medline].
9. Suzuki T, Delgado-Escueta AV, Aguan K, et al. Mutations in EFHC1 cause juvenile myoclonic epilepsy. Nat Genet. Aug 2004;36(8):842-9. [Medline].
10. Pal DK, Evgrafov OV, Tabares P, et al. BRD2 (RING3) is a probable major susceptibility gene for common juvenile myoclonic epilepsy. Am J Hum Genet. Aug 2003;73(2):261-70. [Medline].
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12. Specchio LM, Gambardella A, Giallonardo AT, Michelucci R, Specchio N, Boero G, et al. Open label, long-term, pragmatic study on levetiracetam in the treatment of juvenile myoclonic epilepsy. Epilepsy Res. 2006;71(1):32-39. [Medline].
13. Morris GL, Hammer AE, Kustra RP, Messenheimer JA. Lamotrigine for patients with juvenile myoclonic epilepsy following prior treatment with valproate: results of an open-label study. Epilepsy Behav. Aug 2004;5(4):509-12. [Medline].
14. Prasad A, Kuzniecky RI, Knowlton RC, et al. Evolving antiepileptic drug treatment in juvenile myoclonic epilepsy. Arch Neurol. Aug 2003;60(8):1100-5. [Medline].
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Article Last Updated: Nov 29, 2007