Prader-Willi Syndrome is a serious genetic disorder that begins
at birth with no known cure ; causing mental retardation,short stature,low
muscle tone,incomplete sexual development,and its main charecteristic,the
desire to eat everything and anything in sight.
Prader-Willi syndrome was first known as Prader-Labhart-Willi Syndrome after three
Swiss doctors who first described the disorder in 1956. The doctors described a small
group of kids with obesity, short stature and mental deficiency , neonatal hypotonia
(floppiness) and a desire to constantly eat because they are always hungry. Many other
features of PWS have since been described, but extreme obesity and the health problems
associated with being fat are the most prominent features.
Individuals with PWS have some but not all of the same features and symptoms.
PWS is a birth defect. A defect in the hypothalamus, a region of the brain, is
suspected to be the cause.The hypothalamus determines hunger and satiety.They can't fell
satiety,so they always have a urge to eat.Some PWS cases are so out of control thay will
eat bottlecaps,glass,pencils,garbage,bugs,dogfood, and anything else they can stuff in
their mouths.
"The ingenuity and determination of PWS children in surreptitiously obtaining edibles
is almost legendary and belies their cognitive defects. Serial weighing may be the only
way to discover whether such a child is, in fact, stealing food"(Finey,1983).
PWS occurs in about l in 10,000 births. It occurs in both males and females equally and
is found in people of all races and all nations.It is one of the ten most common
conditions seen in genetics clinics.
Young people with PWS resemble each other very much.Most of the time, they look like
brother and sister. Most of PWS people have almond shaped eyes, narrow foreheads,
downturned mouth, thin upper lip and a small chin. Other common features are : obesity ,
they may be short; they have small hands and feet; have a skin picking habit, thick and
sticky saliiva,incomplete sexual development, a curved spine (scoliosis),and chronic
sleepiness.
PWS patients also have similar personalities: talkative, friendly,extreme attempts
towards getting food,arguementivness,repetitve thoughts and behavior, stubbornness,
frequent temper tantrums, and sometimes sudden acts of violence.
Most people with PWS have some degree of mental deficiency. The average IQ of people
with PWS is 65 ,and it ranges from 20 to 90. 41% of PWS people have IQs in the normal
or borderline range.Specific academic weakness in math and writing are common, but
reading and art are considered strengths.A delay in getting to early developmental
milestones is common in PWS. The average IQ testing shows that people with PWS are
mildly retarded, the range is from severely retarded to not retarded, with 40% having
borderline retardation or just a low normal intelligence. Most affected children,
besides their IQ scores, will have many, severe learning disabilities,and will show poor
academic performance no matter what their IQ shows to their mental abilities.
There are many signs and symptoms of PWS that show up before birth.some are decreased
fetal movement in 80-90% and having an abnormal delivery in 20-30% due to having a
really floppy baby. There are two distinct clinical stages of PWS.
Stage 1
Babys with PWS are called "floppy babies"a lot. Thats because they have weak muscles,
officially it is known as hypotonia. This hypotonia,which almost always occurs, could be
mild to severe. Neonatal hypotonia makes sucking difficult, and a special feeding method
called a gavage is used.A gavage the placing of a tube into the stomach through the
mouth.They use it during the first days of life a lot.. Decreased caloric intake from the
special feeding difficulties may lead to failure to gain weight. To keep the baby's
weight under control supervision by a professional nutritionist or a specialist who
understands the syndrome might be necessary. Physical therapy is strongly recommended to
improve muscle tone.
When the muscle tone improves enough, an increased appetite and weight gain starts.The
beginning of the second stage has begun. This hypotonia does not progress and begins to
improve between 8 and 11 months of age in most cases.It improves,but it is never
completly normal.
Stage 2
stage 2 occurs between one and two years of age and is characterized by an appetite
that can not be satisfied whic causes excessive weight gain. Speech problems,
sleepiness, decreased pain sensitivity, skin picking habits and decreased growth are
also characteristics of the second stage of PWS. The personality problems develop between
ages 3 and 5 years also.
Most parents who have a kid with PWS do not have another kid affected with PWS . The
cases of PWS are thought by scientist to have occured by chance in isolated flukes of
nature. But, there have been reports of families with more than one kid with PWS, but it
is not common. Fewer than a dozen families with more than one affected offspring have
ever been reported.
A blood sample for high resolution chromosome analysis is drawn on anyone who is though
to have PWS.This will check out the chromosones. Chromosomes are packages of information
found in the cells of our bodies. Each cell has a set of 46 chromosomes, which come in
pairs numbered from 1 to 23. Parents contribute with one chromosome from each
pair.Okay,now Prader-Willi Syndrome is caused by the absence of some genes on one of the
chromosones that affect the functionimg of the hypothalamus.Many laboratories around the
world are researching this. About three-fourths of people with PWS have a tiny piece
missing from one member of the pair of chromosone fifteens (the one inherited by the
father).The other one fourth are missing the dads contribution to this part of the
chromosone by missing all of the fathers chromosone fifteen and having two copies the
mother's chromosone fifteen.The genes in this region are not functional and noone
understands why.
As soon an the kid has improved muscle tone, and has increased its appetite, and is old
enough to get move on the floor,than any food that can be easily gotten must be moved to
a safer,out-of-reach place. To make inappropriate "food" unavailable to the kid with PWS,
parents must learn special patterns of food storage and handling
Sleepiness during the day and napping a lot are some of the common features of PWS.
Recently, studies have show that there is a strong link between this and sleep quality.
Some of the types of sleep disorders that have been described in PWS affected people are:
disturbance to the sleep\ wake cycle, obstructive sleep apnea, hypoventilation syndromes
and narcolepsy. Although patients with PWS fall asleep very quickly, their sleep period
is significantly disrupted with frequent awakenings and abnormal patterns of rapid eye
movements sleep (rems). Obstructive sleep apnea occurs with increased upper airways
resistance, either from enlarged tonsils , relaxation of the upper airway musculature, or
from structural airway anomalies. Sometimes actual pauses in breathing during sleep can
occur.. Narcolepsy, which involves sleep attacks and occasional loss of muscle tone,
Short stature is also a common feature of almost all PWS affected people (80-100%),
but birth height is usually normal. The average adult height is 59 inches in women and 61
inches in men. Abnormal growth hormone response suggests a possible dysfunction of the
hypothalamus and, growth hormone deficiency as a contributing factor in short stature.
Improvement in growth rate and decreased rate of weight gain have recently been
demonstrated in several growth hormone-deficient children with PWS after six months of
growth hormone treatment
Other significant actions of growth hormone that have been reported is an improvement of
muscle mass, muscle strength, energy expenditure, bone mineralization ,sexual development
,and also a decrease in fat mass ,have led to further investigations in people with PWS.
Children with PWS have distinct behavioral abnormalities because of all the frustrations
associated with the syndrome. These behaviors may begin as early as two years of age.
They will get a variety of different eating behaviors like foraging for food, secretly
eating large amounts of food, and other attempts to continue eating. Other problems
include verbally and physically aggressive behaviors such as lying, stealing, scratching
and skin picking. Tantrums and unprovoked outbursts are common among children and youths
with PWS.
People with mild cases of PWS can do many things their normal peers can do,such as go to
school,get jobs,and sometimes even move away from home.However they need a lot of
help.Kids going to school would need to be enrolled in special education
programs(Otherwise they'd be eating their pencil and paper).They need to be constantly
supervised.
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