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.

It is estimated that 7-10% of patients with this syndrome have a defect in a gene called the maternal uniparental disomy (UPD) for chromosome 7. However, a cause can not be identified for most patients. Most cases occur in a person whose family has no history of the disease.

The features associated with Russell-Silver syndrome have been linked to many other genetic problems such as:

• Chromosome rearrangements
• Autosomal dominant and recessive families (rarely reported)
• Abnormal methylation of chromosome 11p15

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

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

The condition is usually diagnosed no later than early childhood. The doctor will perform a physical exam. Signs include a:

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

There are no specific laboratory tests for the diagnosis of Russell-Silver syndrome. However, the following tests may be done:

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