Conditions

Angelman syndrome

Angelman syndrome (AS) is a behavioural disorder characterised by seizures, severe developmental delay, absent speech and ataxia.

  • Epidemiology
  • Clinical Presentation
  • Physical Signs
  • Complications

Epidemiology

  • Incidence: 1 in 12 000-40 000
  • All ethnic groups
  • Male = Female

Clinical Presentation

  • Severe developmental delay
  • Profound speech delay. Many children do not speak more than 3-4 words.
  • Seizures
  • Specific behaviour with excitability and inappropriate laughter.
  • Movement and balance problems
  • Wide based ataxic gait.
  • Sleep disorder.
  • Less commonly there is hypopigmentation

 

Physical Signs

  • Microcephaly
  • Jerky gait
  • Increased muscle tone
  • Down-turned corners of the mouth
  • Wide mouth
  • Deep set eyes
  • Prominent chin
  • Hypotonia
  • Happy and sociable affect

 

Complications

  • Almost all patients develop seizures. Usual onset is by the second year.
  • Scoliosis occurs in 40% of adults
  • Loss of mobility and contractures