Definition

Prader-Willi syndrome (PWS) is group of symptoms caused by a rare genetic problem. It can cause a variety of problems with growth and development.

Causes

PWS is caused by a random genetic defect. The defect is most often caused by a gene from the father.

Risk Factors

There are no known risk factors. About 1% may have a family history.

Symptoms

Some physical features in people with PWS are:

• Almond-shaped eyelid openings
• Poor eye alignment
• A thin upper lip
• A downturned mouth
• A narrow forehead
• Small hands and feet

Other symptoms of PWS can change as the child ages.

Infants may have:

• Problems feeding
• Slow growth
• A weak, squeaky cry
• Sleepiness

Toddlers may have:

• A delay in normal development, such as language skills and walking
• Behavior problems, such as temper tantrums and stubbornness
• Short stature compared to peers in the family
• Increased hunger

Older children may have:

• Insatiable hunger
• Increased behavior problems, such as:
  • Anger and inflexibility
  • Problems with transitions
  • Mood swings
  • Obsessive habits
• Learning problems
• Fatigue
• Sleep problems
• High threshold for pain
• Problems sensing temperature extremes

Diagnosis

The doctor will ask about your child's symptoms and health history. This may be enough to suspect PWS.

A genetic test can help to confirm the diagnosis. This test is done with a sample of blood.

Treatment

There is no cure. Lifetime treatment will be needed to manage symptoms. Some methods are:

• Nutrition support to make sure the child gets the right amount of calories and maintains a healthy weight
• Lifestyle changes, such as exercising regularly
• Physical, speech, and occupational therapy to help with developmental delays
• Special education services
• Medicines to improve feeding and behavior issues as well as:
  • Growth hormones to normalize height
  • Hormone replacement therapy to help with development

Prevention

There are no known guidelines to prevent PWS.