Sotos Syndrome

What is Sotos syndrome?

Sotos syndrome is a disorder characterized by a distinctive facial appearance, overgrowth in childhood, and learning disabilities or delayed development of mental and movement abilities.

What are the symptoms of Sotos syndrome?

Characteristic facial features include a long, narrow face; a high forehead; flushed (reddened) cheeks; and a small, pointed chin. In addition, the outside corners of the eyes may point downward (down-slanting palpebral fissures). This facial appearance is most notable in early childhood. Affected infants and children tend to grow quickly; they are significantly taller than their siblings and peers and have an unusually large head. However, adult height is usually in the normal range. Other symptoms include:

Macrocrania (large skull) without megalencephaly (large brain)
Characteristic structural changes in the brain on MRI (extra fluid, midline changes
High arched palate (roof of mouth is narrow and arched upward)
Increased birth length and weight
Disproportionately large hands and feet
Low muscle tone
Developmental delay
Expressive language delay
Advanced bone age
Premature tooth eruption, soft enamel
Poor fine motor control
Learning disabilities
Frequent upper respiratory infections
Behavioral disturbance

What causes Sotos syndrome?

Sotos syndrome is caused by an abnormality (mutation) in the NSD1 gene, and is inherited in an autosomal dominant manner.

How is Sotos syndrome diagnosed?

Making a diagnosis for Sotos can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The diagnosis of a patient with the typical craniofacial configuration and excessive growth can often be made at the first site. The diagnosis can be confirmed by DNA studies by FISH (fluorescence in situ hybridization) analysis to detect microdeletions or MLPA (multiplex ligation-dependent probe amplification). DNA analysis by sequencing would determine NSD1 mutations.

What are the treatments for Sotos syndrome?

The treatment of Sotos syndrome is directed toward the specific symptoms that are apparent in each individual. Treatment may require the coordinated efforts of a team of specialists. There is currently no cure.