Definition of Russell-Silver syndrome:

Russell-Silver syndrome is a disorder present at birth that involves poor growth, low birth weight, short height, and differences in the size of the two sides of the body.

Causes, incidence, and risk factors:

An estimated 7 - 10% of patients with this syndrome have a defect called the maternal uniparental disomy (UPD) for chromosome 7. In another 35% of patients, there is an abnormality on chromosome 11 that affects genes important in growth. However, a cause cannot be identified in most patients. Most cases occur in people with no family history of the disease.

The estimated number of people who develop this condition varies greatly. Some say it affects about 1 in 3,000 people. Other reports say it affects 1 in 100,000 people. Males and females are equally affected.

Symptoms:

• Arms and legs of different lengths
• Coffee-with-milk (cafe-au-lait) colored spots
• Curving of the pinky toward the ring finger
• Delayed bone age
• Failure to thrive
• Gastroesophageal reflux disease
• Kidney problems, such as:
  • Horseshoe kidney
  • Hydronephrosis
  • Posterior urethral valves
  • Renal tubular acidosis
• Low birth weight
• Normal width of head
• Poor growth
• Short arms
• Short height (stature)
• Short, stubby fingers and toes
• Swelling of the food pipe (esophagus)
• Wide forehead with a small triangle-shaped face and small, narrow chin

Signs and tests:

The condition is usually diagnosed by early childhood. The doctor will perform a physical exam. Signs include:

• Small, pointed chin
• Thin, wide mouth
• Triangle-shaped face with broad forehead

There are no specific laboratory tests to diagnose Russell-Silver syndrome. However, the following tests may be done:

• Blood sugar
• Bone age testing
• Genetic testing
• Growth hormone
• Skeletal survey (to rule out other conditions that may mimic Russell-Silver syndrome)

Treatment:

Growth hormone replacement may help if this hormone is lacking. Other treatments include:

• Making sure the person gets enough calories
• Physical therapy
• Special education

Many specialists may be involved in treating this condition:

• A doctor specializing in genetics can help diagnose Russell-Silver syndrome.
• A gastroenterologist or nutritionist can help develop the proper diet to enhance growth.
• An endocrinologist may prescribe growth hormone, if it is needed.
• Genetic counselors and psychologists may also be involved.

Expectations (prognosis):

Older children and adults do not show typical features as clearly as infants or younger children. Intelligence may be normal, although the patient may have a learning disability.

Complications:

• Self esteem and emotional problems related to appearance
• Chewing or speaking difficulty if jaw is very small
• Learning disabilities

Calling your health care provider:

Call your health care provider if signs of Russell-Silver syndrome develop. The doctor may refer you to a genetic professional for a full evaluation and chromosome studies.