Insatiable Hunger and Low Metabolism
Although it is rare, Prader Willi Syndrome (PWS) is the most common genetic cause of potentially life-threatening childhood obesity. The Prader-Willi Syndrome Association explains, "A chronic feeling of hunger that, coupled with a metabolism that utilizes drastically fewer calories than normal, can lead to excessive eating and life-threatening obesity."
The International Prader-Willi Syndrome Organization (IPWSO) notes that the two "hallmark characteristics" of Prader-Willi Syndrome are extraordinarily low metabolism and an insatiable hunger. IPWSO quotes Dr. Hans Zellwegger about the degree of this eating compulsion, “PWS children constantly appear plagued by a relentless hunger that dominates their lives. The presence of this insatiable urge to eat, which is beyond the control of the patient, his family, or physician, becomes the primary focus for the child and inhibits all other activities and interest.”
Parents of children with PWS often have to restrict the child’s access to food and lock the kitchen cabinets and refrigerator.
Symptoms of Prader Willi Syndrome
Infants with Prader Willi Syndrome present with weak muscle tone and reduced bone mineral density, have difficulty feeding, poor growth, and delayed development. At first, they will have trouble growing and gaining weight. Then in early childhood, usually between 1 and 6 years of age, the appetite becomes exaggerated to an extreme that leads to chronic consumption and obesity.
Infants with Prader Willi Syndrome may exhibit symptoms at birth such as a small and floppy appearance. Other physical appearances are almond shaped eyes, a narrow bifrontal skull, short stature, and very small hands and feet when compared to the rest of the body. Male newborns may have undescended testicles. Children may have delayed or incomplete sexual development.
Children who have Prader Willi Syndrome have some cognitive impairment and learning disabilities, as well as poor motor skills. Temper tantrums, stubbornness, and compulsive behavior and sleep disorders are also common.
Most patients with PWS are incapable of having children.
Causes of Prader Willi Syndrome
Discovered in 1956, doctors at first had no idea about what was causing the features of Prader-Willi Syndrome. In 1981, it was discovered that many afflicted with PWS had the same gene segment missing from one of their chromosomes. It also was found that the missing gene segment on chromosome 15 was responsible for about seventy percent of Prader Willi Syndrome cases.
In another twenty-five percent of cases, a person afflicted with Prader Willi Syndrome will have inherited two copies of chromosome 15 from the mother instead of a single copy from each parent.
All children of all races are susceptible and the possibility of a child having it is about one in fifteen thousand.
Treatment for Prader Willi Syndrome
There is no cure for PWS. Growth hormone has been approved by the Food and Drug Administration to treat Prader Willi Syndrome. The hormone helps to improve strength and agility, height, lean muscle mass, distribution of weight, stamina, and the density of bone mineral. There are concerns that taking growth hormone can lead to sleep apnea, so children receiving growth hormone treatment need annual sleep studies.