Myoclonic-astatic epilepsy, also known as Doose syndrome, is a type of idiopathic childhood epilepsy presenting with astatic as well as myoclonic component. It presents in children with previously normal development but can cause some degree of mental disturbance later in life.
Presentation
Myoclonic-astatic epilepsy (MAE) consists of both myoclonic and astatic components. This disease can be accompanied by other types of seizures, such as absence, complex partial and generalized tonic-clonic or be atypical in presentation [1]. On more rare occasions, a diagnosed syndromic epilepsy can precede another kind as in the example provided by Auvin et al., who described a case of a young male suffering from myoclonic-astatic epilepsy successive of myoclonic epilepsy. Auvin et al. also described an MAE presenting before juvenile myoclonic epilepsy [2]. Episodes of seizures in MAE are documented to be triggered by physical stimuli, including tactile or acoustic provocation in early presentation [3].
Myoclonic seizures are characterized by brief jolting motions in muscles of axial skeleton and extremities. Likewise, more indistinct seizures appear as small twitches or incoherent sounds. If extremity muscles are affected, the person falls as if thrown on the ground but most commonly afflicted person regains equilibrium and avoids serious injury [4].
Astatic seizures, on the other hand, are manifested by a short loss of tone e.g. may cause the person to appear nodding. This type of seizure typically supersedes a myoclonic one. Late manifestations in addition to previously described include tonic vibrations as well as axial tonic seizures. In negative dynamics of the disease, seizures become more frequent and exhibit in the mornings amid sleep. Moreover, a risk of status epilepticus, absence seizure is possible subsequent to MAE episodes [4].
Mental development in affected children ranges from normal to profound mental retardation [5] [6]. Some behavioral issues bear similarity to autism spectrum disorders presenting as defective social interaction skills, lack of sympathy, tendency to be uncompromising and have a short extent of interests. Children with MAE also exhibit problems with depression, attention span, and aggressive behavior, although the latter is thought to be found less often [7].
Entire Body System
- Falling
Atonic drop attacks appear to be a common cause of ictal epileptic falling in MAEE. [ncbi.nlm.nih.gov]
Both of these words mean ‘loss of tone’ which causes the person to fall to the ground. [epilepsy.org.uk]
Gastrointestinal
- Persistent Vomiting
Five of our patients discontinued the ketogenic diet in less than 3 months (four because of lack of effectiveness and one because of persistent vomiting). [ncbi.nlm.nih.gov]
Psychiatrical
- Short Attention Span
Hyperkinesia, short attention span and emotional lability were the most frequent complaints. [ncbi.nlm.nih.gov]
Neurologic
- Drop Attacks
Atonic drop attacks appear to be a common cause of ictal epileptic falling in MAEE. [ncbi.nlm.nih.gov]
[…] my·o·clon·ic a·stat·ic ep·i·lep·sy a petit mal variant characterized by atonic (drop attacks) and tonic or tonic-clonic attacks in neurologically disabled for example, hemiplegic, ataxic children with mental retardation; characterized in EEG by 2-second [medical-dictionary.thefreedictionary.com]
- Myoclonus
CONCLUSIONS: These neurophysiologic findings indicate that epileptic myoclonus in LGS originates from a stable generator in the frontal cortex, to spread to contralateral and ipsilateral cortical areas, whereas myoclonus in MAE appears to be a primary [ncbi.nlm.nih.gov]
It also differs from typical juvenile myoclonic epilepsy (JME) in its mode of inheritance and action myoclonus. We herein reported a 20-year-old male patient with non-progressive familial myoclonus epilepsy. [ci.nii.ac.jp]
Eyelid myoclonus Expand Eyelid myoclonus Section Eyelid myoclonus may occur either as a very short event lasting 12 s without any detectable impairment of consciousness or, as in absences with eyelid myoclonus, be prolonged and accompany an absence seizure [epilepsyontario.org]
- Dizziness
Common side effects may include dizziness, drowsiness, and fatigue. [stlukes-stl.com]
We went home with a prescription for Keppra, while Nora was dizzy and disoriented from the initial high dose. After 3 unexplained seizures in 3 weeks, Nora got an appointment with Dr. [blogs.oregonstate.edu]
Workup
Myoclonic-astatic epilepsy (MAE) can be diagnosed by findings on electroencephalogram (EEG). In early stages of the disease EEG can appear normal but after advancement of MAE, some findings may be exhibited. These results include short flares of spikes or waves in 2-5 Hz frequency which are combined with polyspikes and wave complexes. Interestingly, a study proposed that the second component of the spike-wave tends to be more positive, correlating to the severity of the seizure [8]. Furthermore, data of spike-wave complexes ranging in frequency 4-7 Hz tend to accompany photosensitivity. Parietal theta and background slowing are also present in EEG. A conglomeration of spike-waves and background slowing can exist after seizure episodes and occur in the time of sleep with no clinical manifestations or disturbances in the sleep cycle. Additionally, occipital activity at 4 Hz can be established, it is typical for such finding to be depressed after the opening of the eyes [4].
EEG in combination with functional magnetic resonance imaging (fMRI) can detect generalized spike and wave (GSW) signals that are associated with blood oxygen level dependent (BOLD) signal changes. Such signals are sought in the thalamus, cerebellum, premotor cortex, and in the putamen. Likewise, deactivation areas can be found in default mode network [9].
International league against epilepsy (ILAE) developed criteria to identify MAE [4]. These are:
- Unremarkable cerebral, behavioral and physical development before the onset of seizures;
- An encounter of myoclonic, myoclonic-astatic, astatic seizures during the developmental period of 7 months to 6 years;
- EEG findings of generalized spikes or polyspike-wave discharges at 2-3 Hz with an absence of focal spikes;
- Exclusion of other syndromes, specifically, cryptogenic Lennox-Gastaut syndrome, benign or severe myoclonic epilepsy.
Nevertheless, MAE is purely an electroclinical diagnosis as there is an absence of diagnostic tests.
EEG
- Hypsarrhythmia
Infantile spasms (West syndrome) West syndrome usually occurs in the first year of life and consists of the triad of infantile spasms, developmental deterioration, and a hypsarrhythmia pattern on EEG. [emedicine.medscape.com]
The origin of hypsarrhythmia and tonic spasms in West syndrome: evidence from a case of porencephaly and hydrocephalus with focal hypsarrhythmia. Brain Dev. 1999;21(2):129-31.Bruyere H, Lewis S, Wood S, MacLeod PJ, Langlois S. [malattierare.regione.veneto.it]
West Syndrome is characterized by infantile spasms, developmental regression, and a specific pattern on electroencephalography (EEG) testing called hypsarrhythmia (chaotic brain waves). [epilepsywarriors.org]
West Syndrome Edit This is a triad of developmental delay, seizures termed infantile spasms, and EEG demonstrating a pattern termed hypsarrhythmia. Onset occurs between 3 months and 2 years, with peak onset between 8-9 months. [house.wikia.com]
Effect of ACTH therapy for epileptic spasms without hypsarrhythmia. Epilepsia 46(5):709-15, 2005. Yanagaki S, Oguni H, Yoshii K, Hayashi K, Imai K, Funatsuka M, Osawa M. [twmu.ac.jp]
- Spike-and-Slow-Waves
EEG showed long sequences of generalised irregular spike and slow waves. [ncbi.nlm.nih.gov]
Myoclonic-atonic seizures manifest with discharges of irregular spike-wave or polyspike-wave complexes at a frequency of 2.5 to 3 Hz, or faster. Atonia is usually concurrent with the slow wave of a single- or polyspike-wave complex. [medlink.com]
Google Scholar | Medline | ISI Tassinari CA, Bureau M., Dravet C., et al: Epilepsy with continuous spikes and slow waves during slow sleep—otherwise described as ESES (epilepsy with electrical status epilepticus during slow sleep), in Roger J, Bureau [journals.sagepub.com]
- Multifocal Spikes
LTG, lamotrigine; M, myoclonic seizure; MA, myoclonic-astatic seizure; MF, multifocal spikes; PHT, phenytoin; PSW, diffuse polyspike and wave complexes; SBA, slowing of background activity consisting mainly of theta rhythm; SW, diffuse spike and wave [omicsonline.org]
Treatment
Little is known about the use of newer antiepileptic treatments (AET) in MAE. The purpose of this study was to describe the characteristics, treatment, and outcome of a contemporary MAE cohort exposed to the new generation AET. [ncbi.nlm.nih.gov]
They experienced from 2-8 seizures daily before starting treatment with TPM. [jpgmonline.com]
Additional data analysis will aim at describing possible correlations between treatment response and cognitive outcome and will focus on delineating distinctive subgroups of MAE. [thieme-connect.com]
Prognosis
CONCLUSIONS: MAE onset in patients with refractory seizures occurs earlier than in those with favorable prognosis. Prognosis was excellent when EEG findings show no focal spike discharges. [ncbi.nlm.nih.gov]
Early onset and focal spike discharges as indicators of poor prognosis for myoclonic-astatic epilepsy. Brain Dev. 2014 Aug;36(7):613-9. MAE onset in patients with refractory seizures occurs earlier than in those with favorable prognosis. [pediatricfocus.wordpress.com]
Prognosis Prognosis is variable, ranging from normal neurodevelopmental outcome and complete seizure remission after several years, to severe intellectual disability and intractable seizures. [orpha.net]
Inoue T, Ihara Y, Tomonoh Y et al (2013) Early onset and focal spike discharges as indicators of poor prognosis for myoclonic-astatic epilepsy. Brain Dev Google Scholar 14. [doi.org]
Etiology
Abstract The majority of severe epileptic encephalopathies of early childhood are symptomatic where a clear etiology is apparent. [ncbi.nlm.nih.gov]
Purpose: Myoclonic-astatic epilepsy (MAE) is a generalized epileptic syndrome of childhood with an unknown etiology with a variable evolution. [moh-it.pure.elsevier.com]
Etiology Exact etiology is unknown but thought to be genetic. Several genes have been identified in patients with MAE, with and without a family history of generalized epilepsy with febrile seizures-plus (GEFS+) (see this term). [orpha.net]
Epidemiology
Epilepsy, Part I, Basic Principles and Diagnosis, Volume 107, in the Handbook of Clinical Neurology series offers a comprehensive review of our knowledge of the field today, including epidemiology, basic mechanisms, animal models, and topics of increasing [books.google.com]
Particular updates include full coverage of new developments in epidemiology, genetics, classification, imaging, drug therapy and other treatments. [books.google.ro]
Summary Epidemiology The incidence is approximately 1/10,000 children. Boys are more frequently affected than girls. Clinical description In 94% of cases, onset occurs during the first 5 years of life, most commonly between the ages of 3-4 years. [orpha.net]
Pathophysiology
To study the pathophysiologic mechanism of astatic seizures in a patient with myoclonic astatic epilepsy of early childhood, ictal magnetoencephalography was recorded and the neuronal pathway involved was analyzed. [ncbi.nlm.nih.gov]
Pathophysiology Myoclonic seizures are generally the product of hypersynchronous, generalized cortical discharges. These discharges arise from hyperexcitable neuronal networks. [emedicine.medscape.com]
In this article, the author details the clinical manifestations, pathophysiology, EEG, and optimal management of patients with myoclonic-atonic seizures. [medlink.com]
The clinical picture of Glut1 defects and the understanding of the pathophysiology of this disease have significantly grown... [readbyqxmd.com]
Polysomnographical assessment of the pathophysiology of West syndrome. Brain Dev. 2001;23(7):523-7.Hayashi M. Neuropathology of the limbic system and brainstem in West syndrome. [malattierare.regione.veneto.it]
Prevention
RUF seemed particularly effective in the prevention of myoclonic-astatic seizures (comparable with drop attacks in Lennox-Gastaut-Syndrome, for which RUF is particularly effective). Some loss of efficacy was noticed in the long-term observation. [ncbi.nlm.nih.gov]
The prognosis of Lennox-Gastaut Syndrome is generally guarded Please find comprehensive information on Lennox-Gastaut Syndrome regarding definition, distribution, risk factors, causes, signs & symptoms, diagnosis, complications, treatment, prevention, [dovemed.com]
AEDs are used to prevent recurrent seizures. [stlukes-stl.com]
Any number of medications may be used to both prevent and treat seizures. Generally after three medications are tried, different treatment should be considered. [en.wikipedia.org]
Medication Any number of medications may be used to both prevent and treat seizures. Generally after three medications are tried, different treatment should be considered. [ipfs.io]
References
- Babu SS, Peter CS, Mogadati S, Joseph PM, Reddy N, Gupta P.Three siblings with multiform seizures: An unusual presentation of Doose syndrome. Natl Med J India. 2014;27:314–15.
- Auvin S, Lamblin MD, Cuvellier JC, Valle L. A patient with myoclonic epilepsy in infancy followed by myoclonic astatic epilepsy. Seizure. 2012;21:300–303.
- Dragoumi P, Chivers F, Brady M, et al. Epilepsy with myoclonic–atonic seizures (Doose syndrome): When video-EEG polygraphy holds the key to syndrome diagnosis. Epilepsy Behav Case Rep. 2016;5:31-33.
- Kelley SA, Kossoff EH. Doose syndrome (myoclonic-astatic epilepsy): 40 years of progress. Dev Med Child Neurol. 2010 Nov;52(11):988-93.
- Stephani U. The natural history of myoclonic astatic epilepsy (Doose syndrome) and Lennox–Gastaut syndrome. Epilepsia. 2006;47(2):53–5.
- Inoue T, Ihara Y, Tomonoh Y, et al. Early onset and focal spike discharges as indicators of poor prognosis for myoclonic-astatic epilepsy. Brain Dev. 2014 Aug;36(7):613-9.
- Trivisano M, Specchio N, Cappelletti S, et al. Myoclonic astatic epilepsy: an age-dependent epileptic syndrome with favorable seizure outcome but variable cognitive evolution. Epilepsy Res. 2011;97:133-141.
- Oguni H, Fukuyama Y, Tanaka T, et al. Myoclonic–astatic epilepsy of early childhood – clinical and EEG analysis of myoclonic–astatic seizures, and discussions of the nosology of the syndrome. Brain Dev 2001;23:757–64.
- Moeller F, Groening K, Moehring J. EEG-fMRI in myoclonic astatic epilepsy (Doose syndrome). Apr. 2014; 82(17):1508-1513.