Prader-Willi syndrome

• 759.81 Prader-Willi syndrome1

• Q87.1 Congenital malformation syndromes predominantly associated with short stature2

• 5C: Impaired motor function and sensory integrity associated with nonprogressive disorders of the central nervous system—congenital origin or acquired in infancy or childhood

Description

• Lack of impression from several imprinted genes3
• Genetic disorder characterized by
  • Specific facial features such as almond shaped eyes
  • Hypotonia
  • Hypogonadism
  • Strabismus5
  • Short stature
  • Cognitive deficits
  • Inability to regulate appetite
  • Males with undescended testicles6
  • Small hands and feet5,6

Essentials of Diagnosis

• Two stages3,4
  • Stage 1 occurs during infancy with hypotonia and poor suck/swallow reflex that may result in failure to thrive
  • Stage 2 generally begins about 2 years of age with lack of satiety progressing to obesity

General Considerations

• Growth hormone deficiency5
• Patients often develop complications from obesity and osteoporosis as they age8

Demographics

• 1 in 15,000 individuals4
• Affects females and males equally

Signs and Symptoms

• Poor suck/swallow ability at birth
• Hypotonia in infancy
• Specific facial features such as almond shaped eyes
• Hypogonadism
• Strabismus5
• Short stature
• Obesity
• Cognitive deficits
• Inability to regulate appetite
• Hypogenitalism; males with undescended testicles6
• Small hands and feet5,6
• Developmental delay

Functional Implications

• May require gastrostomy tube5
• Cognitive impairment
• Learning disabilities
• Poor speech articulation
• Behavioral problems7
• Obsessive-compulsive disorder7
• Scoliosis7

Possible Contributing Causes

• Deletion in portion of chromosome 15q115
• Possibly due to dysfunction of hypothalamus4

Differential Diagnosis8

• Obsessive-compulsive disorder
• Failure to thrive
• Fragile X syndrome
• Growth hormone disorder

Laboratory Tests

• DNA methylation analysis4,5
• Magnetic resonance imaging (MRI) to assess pituitary gland8

Imaging

• Fluorescence in situ hybridization (FISH)
• Chromosomal Microarray Analysis (CMA)
• Standard radiograph to screen for scoliosis

• Deletion in portion of chromosome 15q11 detected by FISH or microarray3

Medication

• Human growth hormones8
  • Saizen
  • Genotropin
  • Humatrope
  • Nutropin
  • Serostim

• Orthopedist for possible scoliosis
• Endocrinologist
• Geneticist
• Nutritionist
• Ophthalmologist
• Gastroenterologist
• Psychiatrist
• Occupational therapist
• Speech therapist

• Poor head control
• Poor trunk control
• Inability to sit independently

• Bayley Scales of Motor Development or Bayley II
• Peabody Scales of Motor Development
• Movement Assessment of Infants
• Neonatal Behavioral Assessment Scale
• Early Intervention Developmental Profile
• Test of Infant Motor Performance
• Alberta Infant Motor Scale
• Bruininks Oseretsky Test of Motor Proficiency
• Skin fold analysis
• Six-minute walk test

• Behavior modification
• Developmental activities
  • Acquisition of motor milestones through facilitation
• Therapeutic exercise
  • Strengthening
  • Aerobics

• Sustain prone position on elbows ...