Transcript Epilepsy in Down Syndrome without videos or pictures

Epilepsy in Down’s Syndrome
Dr Sameer Zuberi
Paediatric Neurologist
Fraser of Allander Neurosciences Unit
Royal Hospital for Sick Children
Glasgow
What is epilepsy ?
• An epileptic seizure is the
behavioural manifestation of
an abnormal
hypersynchronous electrical
discharge from cortical
neurons
• Epilepsy is recurrent epileptic
seizures not provoked by
everyday stimuli
Almost every condition affecting the cerebral cortex can result in epilepsy
Chromosome disorders & Epilepsy
•
6% of (172) patients with learning difficulties and
epilepsy have a chromosome abnormality (Ieshima
A et al 1998)
•
Rises to 50% in patients with seizures and >3
dysmorphic features
•
> 400 chromosomal disorders are associated with
epilepsy and many (≈ 40) have epilepsy as a
common feature. Smaller number have epilepsy as a
consistent feature
•
Chromosome studies rarely ordered when faced with
a child who develops cognitive problems after the
onset of epilepsy
Chromosomal disorders strongly
associated with epilepsy
•
Wolf-Hirschhorn Syndrome (4p-)
•
Miller-Dieker Syndrome (del 17p13.3)
•
Angelman Syndrome
•
Inversion duplication 15 Syndrome
•
Duplication syndromes
– additional segment of material
•
Terminal deletion chromosome 1q
•
Terminal deletion chromosome 1p
•
Deletion syndromes
– Segment genetic material missing
•
Ring 14 syndrome
•
•
Breakpoint disruptions
– Only one or very few genes affected
Ring 20 syndrome
?Phenotype related to gene dosage- haploinsufficiency or “triplo-excess”
How common is epilepsy in Down’s
syndrome?
• Figures depend on size of series, definition of epilepsy,
age of cases, source of population
• Prevalence figures vary from 1 to 9%, compares to
<0.5% in general population
• Are some seizure types such as febrile seizures (0.9%)
less common in Down’s Syndrome?
Postal Survey of 1000 families with a child
with Down’s Syndrome
Mary King and John Stephenson (Fits & Faints 1990)
• Most children do not have epileptic or nonepileptic seizures
• Infantile spasms occurred in 2%
• Syncope appeared to be common including
reflex anoxic seizures and convulsive
syncope
Goldberg-Stern et al. Brain Dev 2001; 23:375-8
• 350 children & adolescents
• 8% had epilepsy (prevalence)
• 47% partial seizures
• 32% infantile spasms
• 21% generalised tonic clonic seizures
Epilepsy Phenotypes in Down Syndrome
• Infantile spasms
• Focal epileptic seizures secondary to acquired
brain lesions
• Reflex / startle epilepsy
• Late onset myoclonic epilepsy in Down’s
Syndrome (LOMEDS)
A bi-modal distribution
Infantile spasms
• 8-10 x more common than in general
population
• 2 groups
– Those symptomatic of perinatal hypoxic brain
injury who have a poor prognosis
– No acquired brain injury. A relatively good
prognosis
Infantile Spasms
• West Syndrome
An electroclinical triad of:
spasms, hypsarrythmia, and
regression or stagnation of
mental abilities
West Syndrome is not synonymous
with Infantile spasms
Classified as symptomatic or
cryptogenic(15%)
Video of behaviour pre-treatment
EEG prior to treatment
EEG during spasm
Treatment options
• Hormonal treatments
• Steroids
– 2mg/kg of prednisolone for 2 weeks
– ACTH
• Vigabatrin
• Pyridoxine
• Sodium valproate
Important to repeat the EEG
Behaviour post treatment in EEG department
EEG post treatment
Eisermann et al. Infantile Spasms in Down Syndrome –
effects of delayed anticonvulsive treatment.
Epilepsy Research 2003; 55:21-7
• 18 patients with spasms
• Correlation between treatment lag
– cessation spasms
– developmental quotient
– autistic features
Video of Sleep Start
EEG during sleep start
Non-epileptic Paroxysmal Disorders
in Down Syndrome
• Syncope
– Associated with congenital heart disease
– Reflex anoxic seizures / reflex asystolic
syncope
• Sleep starts
• Tics / Tourette Syndrome
Focal epileptic seizures
• Can have benign focal epilepsies such as
rolandic epilepsy
• More common are lesional focal epilepsies
– Cyanotic heart disease and abscess
– Stroke related to cardiac disease or to cardiac
surgery
Startle Epileptic Seizures
Guerrini R, Genton P, Bureau M, Dravet C,
Roger J Reflex seizures are frequent in patients
with Down syndrome and epilepsy.
Epilepsia. 1990 Jul-Aug;31(4):406-17.
Seizures with variety of aetiologies but triggered by
sound and touch. Is there reduced cortical
inhibition in Down’s Syndrome?
Late onset myoclonic epilepsy
• Incidence of epilepsy in Alzheimer’s
disease without Down’s Syndrome is 10%
• Incidence of epilepsy in Down’s Syndrome
with Alzheimer’s like dementia is 75%
Late onset progressive myoclonus
Most common after age 50
Associated with dementia
May respond to valproate or
levetiracetam
Occasional generalised
generalised tonic clonic seizures
Also called senile myoclonic
epilepsy