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.
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 . 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 . Episodes of seizures in MAE are documented to be triggered by physical stimuli, including tactile or acoustic provocation in early presentation .
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 .
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 .
Mental development in affected children ranges from normal to profound mental retardation  . 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 .
Entire Body System
- 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]
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]
LEV efficacy against myoclonic seizures has led to its off label use in a variety of conditions associated with myoclonus including post-anoxic myoclonus [ 7 ] and childhood epilepsies with myoclonic seizures [ 8 - 10 ]. [bmcpediatr.biomedcentral.com]
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 . 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 .
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 .
International league against epilepsy (ILAE) developed criteria to identify MAE . 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.
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 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]
West Syndrome is characterized by infantile spasms, developmental regression, and a specific pattern on electroencephalography (EEG) testing called hypsarrhythmia (chaotic brain waves). [epilepsywarriors.org]
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]
EEG showed long sequences of generalised irregular spike and slow waves. [ncbi.nlm.nih.gov]
• EEG shows frequent generalized discharges of spike/polyspike-slow wave at varying frequencies of 2.5 to 3 Hz or higher. • Differential diagnosis is often demanding and requires exclusion of structural epilepsies and epileptic encephalopathies that [medlink.com]
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 M, Dravet C, et al (eds): Epileptic Syndromes in Infancy, Childhood [journals.sagepub.com]
- Multifocal Spikes
spikes; PHT, phenytoin; PSW, diffuse polyspike and wave complexes; SBA, slowing of background activity consisting mainly of theta rhythm; SW, diffuse spike and wave complexes T, tonic seizure; TC: tonic-clonic seizure; VPA, valproic acid; ZNS, zonisamide [omicsonline.org]
- 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.