Early myoclonic encephalopathy

Early myoclonic encephalopathy
ICD-10	G 40.3
MeSH	D004831

For patient information, click Insert page name here Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] ;

Synonyms and keywords: neonatal myoclonic encephalopathy

Overview

Early myoclonic encephalopathy, is a seizure disorder that begins in the neonatal period. It has features like partial or fragmentary erratic myoclonic seizures,massive myoclonus, partial motor seizures (jerking movements of one side)and tonic seizures.

Classification

According to International Classification of Epilepsies and Epileptic Syndromes(ILAE), early myoclonic encephalopathy is categorized as age related, generalized symptomatic epilepsy of non specific etiology.

Pathophysiology

Genetics

• In most cases the disease appears to be inherited as an autosomal recessive trait.

Associated Conditions

• Non-ketotic hyperglycemia
• D-glycemic acidemia
• Methylmalonic acidemia
• Propionic acidemia
• Hyperammonemia due to carbamyl phosphate synthetase deficiency

Causes

Cause is uncertain.

Differentiating Early myoclonic encephalopathy from other Diseases

Early myoclonic encephalopathy has to be differentiated from few other epilepsy syndromes due to similar presentations.

• Ohtahara syndrome
• West syndrome
• Lennox-Gastaut syndrome

Differentiating features are:

Features/Disease	Early myoclonic encephalopathy	West syndrome	Lennox-Gastaut syndrome
Age at presentation	Early infancy	Infancy	Early childhood
Diverse seizures	May or may not be present	Not present	Present
Tonic spasms	May or may not be present	Present	Not present
Response to ACTH	Poor	Good	Poor
Interictal EEG	Suppression bursts	Hypsarrhythmia	Diffuse slow spike wave

Differentiating Early myoclonic encephalopathy from Ohtahara syndrome:

Features/Disease	Early myoclonic encephalopathy	West syndrome
Etiology	Non structural or metabolic	Structural brain lesions
Clinical	Myoclonia and partial seizures	Tonic spasms
Suppression bursts(SB)	More apparent in sleep	Consistently seen in wakeful and sleep states
Course	SB's persist to childhood with transient transformation to hypsarrhythmia	Evolve to hypsarrhythmia and then to diffuse slow spike waves
Transformation	Persists for long period	Evolves to West syndrome and then to Lennox-Gastaut syndrome

Epidemiology and Demographics

Early myoclonic encephalopathy(EME) is a rare disease with only around 30 cases described so far.

Diagnosis

Family History

• There is a high risk of familial recurrence since in most cases the disease appears to be inherited as an autosomal recessive trait.

References

Template:WikiDoc Sources