Figure – This 4-year-old girl has a relatively small head, deep-set ears, a protruding tongue, and a wide mouth-all characteristic features of Angelman syndrome. In addition- although not visible in this photograph-she has intermittent exotropia, a flat occiput, widespaced teeth, and drooling.
This 4-year-old girl was born to a 27-year-old gravida, 1 para 0 mother at 37 weeks' gestation via vaginal delivery. The pregnancy was uncomplicated. Apgar scores were 8 at 1 minute and 9 at 5 minutes. The child's birth weight, head circumference, and length were 3045 g, 33 cm, and 50 cm, respectively. Her mother noted global developmental delays (particularly in the areas of speech and fine motor skills), abnormal sleep habits, obstructive sleep apnea, and seizure disorder. Family history was unremarkable.
Her weight, height, and head circumference were 18 kg (90th percentile), 100 cm (50th percentile), and 48.5 cm (25th percentile), respectively. The child appeared quite happy. She had deep-set eyes, a posteriorly flattened head, intermittent left exotropia, occasional hand flapping, and tremors of her upper extremities. Deep tendon reflexes were 2+ and symmetrical bilaterally, with a downgoing plantar reflex. Results of the remainder of the physical examination were unremarkable.
An electroencephalogram (EEG) showed diffuse slow (2 to 3 Hz), high-voltage delta waves and moderate posterior discharges.
WHAT'S YOUR DIAGNOSIS?
ANSWER: ANGELMAN SYNDROME
Colloquially referred to as "happy puppet" syndrome or marionette joyeuse, Angelman syndrome was first described by Harry Angelman in 1965.1 Characteristic features of this syndrome include unusual facial characteristics, an especially happy demeanor, severe global developmental delays (particularly in language), seizures, and a jerky, marionettelike spasticity.2 Along with its sister condition, Prader-Willi syndrome, Angelman syndrome is commonly cited as a prime example of the effects of abnormal parental genomic imprinting.3,4
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