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WILLIAMS SYNDROME
Williams syndrome is a non-hereditary syndrome which strikes at random and
can cause brain-damage in varying degrees, combined with some physical
side-effects. These include lack of co-ordination, slight muscle weakness,
possible heart defects, and occasional kidney damage. Hypercalcaemia, a high
calcium level, is often discovered in infancy, and normal development is
generally delayed. The incidence of cases is approximately 1 in 20,000.
Diagnosis
Diagnosis is not easy because side-effects vary considerably, but various
clues can be combined to produce a near-certainty. The probable cause of
Williams Syndrome is a micro-deletion of the Elastin Gene on Chromosome 7, and
a blood-test (called the FISH technique) can establish if the Elastin Gene is
in fact missing. The symptoms are of two types, physical and psychological.
Physical symptoms
Facial features provide a clue. All the children have a facial similarity,
referred to as "elfin" features, which include:
- a wide mouth, with large, slack bottom lip
- very retrousse nose with flattened bridge
- slightly "bulgy" cheeks
- irregular teeth widely spaced
- sometimes a squint
The child experiences many early problems, including:
- low birth-weight
- slow weight gain
- sometimes weight loss
- below average growth
- very slow feeding
- restless sleeping
- irritability
- sometimes a hernia
- excessive vomiting leading to dehydration and constipation
- sometimes a raised calcium level
Additionally, all WS children appear to have a slight narrowing of the aorta
above the valve, in many cases insignificant, but occasionally leading to more
serious heart defects.
Psychological symptoms
Hyperactivity is often displayed in early years, exhibited as extreme
uninhibited behaviour, excessive talking (in an inappropriate and
"adult" manner), over-friendliness with strangers, and a compulsion
to talk to adults, while being unable to make friends with peers.
Later on, the child exhibits a high verbal ability leading to artificial
expectations of matching mental ability. He or she may have an obsessional
interest in certain things (e.g. cars, trains, vacuum cleaners, wheels, etc.).
Fear of heights, open stairs, and uneven surfaces is a common symptom. A very
short concentration span and high distractibility adds to learning
difficulties. An emotional immaturity is exhibited by over-reaction to events,
and exaggerated displays of fear, excitement, sadness, and happiness.
The most common clue is hypersensitivity to noise. About 90% of affected
children show great distress on hearing sudden loud noises, such as guns
firing, balloons bursting, Christmas crackers, fireworks etc.
Treatment
There is no "cure" for Williams Syndrome. When hypercalcaemia is
present, a low-calcium diet can stabilise the situation, but any damage done by
birth cannot be reversed. However, early diagnosis means better understanding
of the problems which may arise, leading to a happier life for the child, and
relief and support for the parents. Continuing further education can help to
realise full potential.
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