Williams Syndrome

What Is Williams Syndrome?

Williams syndrome, also known as WS, WMS, and Williams-Beuren syndrome (WBS) is a rare neurodevelopmental genetic disorder in which the individual has mild mental retardation, unusual "elfin" facial features along with a low nasal bridge, cardiovascular disease, and unique personality traits. A person with Williams syndrome tends to have high hypercalcemia (high blood calcium level) and hypercalciuria (high urine calcium level).

An individual with Williams syndrome characteristically has surprisingly advanced verbal skills, is highly sociable and is likely to have an affinity to music. Some experts say that the high verbal skills mask other developmental problems and sometimes contribute towards late diagnoses.

Unlike a significant number of developmental disorders, children with WS are extremely endearing, friendly and social. Parents will generally find them pleasant company.

The disorder is caused by a deletion of approximately 26 genes from the long arm of chromosome 7.

Dr. J.C.P. Williams (born 16 November 1922), a cardiologist from New Zealand first identified and described the syndrome fully, hence its name.

Experts estimate that between 1 in every 7,500 and 20,000 babies are born with Williams syndrome. According to the Williams syndrome association, approximately 1 in 10,000 people worldwide are affected and between 20,000 and 30,000 people in the USA have WS.

Many babies with WS have life-threatening cardiovascular problems. As they get older their ongoing medical care and early life interventions, such as occupational and speech therapies can become costly, unless the individual lives in the UK or Canada, where such services tend to be free-of-charge.

Later problems may include spatial relations, abstract reasoning and numbers. An adult with WS will probably need supportive housing for best results. A person with WS and the right support has a good chance of becoming an active working adult.

Features commonly associated with Williams syndrome

Characteristic facial appearance - small upturned nose, long upper lip length, wide mouth, small chin, puffiness around eyes, and full lips. Those with blue or green eyes may later on in life develop a white lacy pattern around the iris.

Heart and blood vessel problems - in a considerable number of cases the aorta narrows, or the pulmonary arteries narrow. There may be general vascular narrowing (narrowing of most blood vessels), which sometimes may require surgical intervention. Hypertension (high blood pressure) may eventually become a problem. The patient will require regular monitoring.

Hypercalcemia (elevated blood calcium) - blood calcium levels will typically be high. Experts are not sure what the cause is. Patients with hypercalcemia may have colic-like symptoms and be irritable. Some patients may have to follow certain diets, or take medications. In the majority of cases signs and symptoms ease as the child gets older. However, problems with calcium levels and vitamin D metabolism may continue for the rest of the child's life.
Cognitive and developmental features - mild to severe learning disabilities and cognitive challenges are common. Developmental delays are experienced by most children with WS. The child will take longer than other children to learn to walk upright, talk, or become toilet trained (UK: potty-trained). As the child gets older speech, social skills and long-term memory are usually strong, while spatial relations and fine motor skills tend to be weak.

Colic - the infant from the age of 4 to 10 months of age may have long periods of colic. Problems usually resolve. The baby may become irritable. Experts say hypercalcemia may be one of the causes. The child may take longer to acquire proper day-night sleeping patterns.

Feeding problems - babies and young children may have problems when feeding. Experts say that severe gag reflex, poor muscle tone, poor suck/swallow, and tactile defensiveness may cause problems early in life. These difficulties tend to get better as the child grows up.

Hernia - people with WS have a higher chance of having groin (inguinal) and umbilical hernias, compared to others.

Low birth weight - a child with WS will usually have a lower birth rate than his/her siblings. Some may be diagnosed as "failure to thrive" (not putting on weight fast enough). Most adults with WS have a smaller stature than average.

Personality - individuals may be surprisingly endearing. Their expressive language skills are often astonishingly strong. Children with WS are usually very polite. They tend to be more interested in communicating with adults than other children of their age. Most children with WS are not fearful of strangers.

Problems with bones and muscles (musculoskeletal problems) - joints may be lax and there may be low muscle tone early in life. Contractures (joint stiffness) may develop as the child grows. Muscle tone, joint range of motion, and strength respond well to physical therapy (UK: physiotherapy).

Renal (kidney) problems - patients with WS have a slightly higher risk of developing functional or structural kidney problems.

Sensitive hearing (hyperacusis) - children may be more sensitive to specific noise levels or frequencies, which may occasionally be painful or upsetting. As the child gets older the condition generally gets better.

Teeth - children may have wide teeth which are slightly small, with wider-than-normal spacing. Teeth may have an unusual shape or appearance. The individual might have abnormalities of occlusion (aligning the upper and lower teeth, as for chewing or biting). In the majority of cases, these problems can be fixed by an orthodontist.