Prader-Willi syndrome is a rare genetic disorder that results in physical, mental and behavioral problems, including a constant sense of hunger.
Prader-Willi (PRAH-dur VIL-e) syndrome is a rare genetic disorder that results in a number of physical, mental and behavioral problems. A key feature of Prader-Willi syndrome is a constant sense of hunger that usually begins at about 2 years of age.
People with Prader-Willi syndrome want to eat constantly because they never feel full (hyperphagia), and they usually have trouble controlling their weight. Many complications of Prader-Willi syndrome are due to obesity.
Best managed by a team approach, various specialists can work with you to manage symptoms of this complex disorder, reduce the risk of developing complications and improve the quality of life for your loved one with Prader-Willi syndrome.
Signs and symptoms of Prader-Willi syndrome can vary among individuals. Symptoms may slowly change over time from childhood to adulthood.
Signs and symptoms that may be present from birth include:
Other features of Prader-Willi syndrome appear during early childhood and remain throughout life, requiring careful management. These features may include:
Regularly scheduled well-baby visits can help identify early signs of poor growth and development, which can be signs of Prader-Willi syndrome or other disorders.
If you have concerns about your baby's health between well-baby visits, schedule an appointment with your child's doctor.
Prader-Willi syndrome is a genetic disorder, a condition caused by an error in one or more genes. Although the exact mechanisms responsible for Prader-Willi syndrome haven't been identified, the problem lies in the genes located in a particular region of chromosome 15.
With the exception of genes related to sex characteristics, all genes come in pairs — one copy inherited from your father (paternal gene) and one copy inherited from your mother (maternal gene). For most types of genes, if one copy is "active," or expressed, then the other copy also is expressed, although it's normal for some types of genes to act alone.
Prader-Willi syndrome occurs because certain paternal genes that should be expressed are not for one of these reasons:
In Prader-Willi syndrome, a defect on chromosome 15 disrupts the normal functions of a portion of the brain called the hypothalamus, which controls the release of hormones. A hypothalamus that isn't functioning properly can interfere with processes that result in problems with hunger, growth, sexual development, body temperature, mood and sleep.
In most cases, Prader-Willi syndrome is caused by a random genetic error and is not inherited. Determining which genetic defect caused Prader-Willi syndrome can be helpful in genetic counseling.
In addition to having constant hunger, people with Prader-Willi syndrome have low muscle mass, so they need fewer than average calories, and they may not be physically active. This combination of factors makes them prone to obesity and the medical problems related to obesity, such as:
Complications arising from inadequate hormone production may include:
Other complications that can result from Prader-Willi syndrome include:
If you have a child with Prader-Willi syndrome and would like to have another baby, consider seeking genetic counseling. A genetic counselor may help determine your risk of having another child with Prader-Willi syndrome.
Typically, doctors suspect Prader-Willi syndrome based on signs and symptoms. A definitive diagnosis can almost always be made through a blood test. This genetic testing can identify abnormalities in your child's chromosomes that indicate Prader-Willi syndrome.
Early diagnosis and treatment can improve the quality of life for people with Prader-Willi syndrome. A team of health professionals will likely work with you to manage the condition.
Your team may include a doctor who treats hormonal disorders (endocrinologist), behavior specialists, a dietitian, physical and occupational therapists, a mental health professional, a geneticist, and other specialists as needed.
Although specific treatments vary depending on symptoms, most children with Prader-Willi syndrome will need the following:
Most people with Prader-Willi syndrome will need specialized care and supervision throughout their lives. Many adults with the disorder live in residential care facilities that enable them to eat healthy diets, live safely, work and enjoy leisure activities.
As your child approaches adulthood, consider these strategies:
Tips to help you take care of your loved one with Prader-Willi syndrome include the following:
Having a child with Prader-Willi syndrome is challenging and can take a lot of patience. Managing eating problems, behavior and medical issues can impact the whole family.
Some options for coping and support can include:
You may start by seeing your family doctor or your child's pediatrician. He or she may refer you to a pediatric endocrinologist and other specialists as needed.
Here's some information to help you prepare for your appointment. Consider taking a family member or friend along for support and to help you remember information.
To prepare for the appointment, make a list of:
Some basic questions to ask your doctor may include:
Your doctor is likely to ask you a number of questions. Be ready to answer them to reserve time to go over points you want to focus on. For example, your doctor may ask different questions depending on your child's age.
Questions about your baby:
Questions about early childhood: