Sotos Syndrome

What is Sotos syndrome?

Sotos syndrome, also known as cerebral gigantism, is a rare genetic condition that causes children to grow faster than other children their age.

Characteristics of Sotos syndrome include:

• Tall stature.
• Large head with distinct facial features.
• Cognitive impairment (learning disabilities).
• Behavioral challenges.

Who does Sotos syndrome affect?

Sotos syndrome is a genetic condition that can affect any child. Sotos syndrome is the result of a genetic mutation — a change in a gene that makes it not work the way it should. About 95% of cases of Sotos syndrome occur due to a new genetic mutation in an egg or sperm cell. New genetic mutations happen randomly. While less likely to occur, children can inherit the condition if one parent carries the mutated gene and passes it to their child (autosomal dominant); if a parent has Sotos syndrome, any child born to them will have a 50% chance of inheriting it.

How common is Sotos syndrome?

Sotos syndrome is a rare condition that affects an estimated 1 in every 14,000 births. Often, Sotos syndrome shares the same symptoms as other conditions. For this reason, many cases go undiagnosed.

What causes Sotos syndrome?

A mutation in the NSD1 gene causes Sotos syndrome. The NSD1 gene gives your body instructions on how to grow and develop. When a mutation affects the NSD1 gene, your genes can’t regulate your body’s growth, causing children diagnosed with Sotos syndrome to be taller than their peers.

What are the symptoms of Sotos syndrome?

Since Sotos syndrome causes physical overgrowth, children with this diagnosis have some defining characteristics. Physical symptoms of the condition include:

• A high forehead.
• A long, narrow face.
• A pointed chin.
• Downward slanting eyes (palpebral fissures).
• Increased arm span.
• Weak muscle tone (hypotonia).
• Tall stature.

What are the physical complications of Sotos syndrome?

Children diagnosed with Sotos syndrome may have complications including:

• Coordination difficulties.
• Hearing loss.
• Heart and kidney problems.
• Scoliosis.
• Seizures.
• Vision problems.

Treatment is available to address the complications of Sotos syndrome, ensuring that your child lives as happy and as healthy a life as possible.

How does Sotos syndrome affect my child?

Sotos syndrome not only affects your child’s physical development, but it can also affect your child’s central nervous system. The central nervous system is responsible for maintaining the function of your child’s body (spinal cord) and mind (brain).

Since the condition affects your child’s central nervous system, they may face developmental milestone delays during their first few years. Developmental milestones are things that most children can do by a certain age including:

• Cognitive skills (how your child learns, thinks and solves problems).
• Language development (how your child speaks and responds).
• Physical development (how your child perfects their motor skills).
• Social and emotional skills (how your child plays and interacts with other people).

Because your child’s central nervous system functions differently due to a genetic mutation, people with Sotos syndrome commonly have issues with cognitive function (intellectual disabilities).

Differences in how your child learns and plays can affect how your child behaves. Behavioral symptoms of Sotos syndrome include:

• Anxiety.
• Attention-deficit/hyperactivity disorder (ADHD).
• Autism spectrum disorder.
• Impulsive behaviors.
• Socialization difficulties.
• Tantrums.

How does Sotos syndrome differ in adults and children?

Children with Sotos syndrome experience physical growth at a rate much higher than their peers of the same age. Children diagnosed with Sotos syndrome will often be taller than other children, but as they grow into adults, their height is no longer an anomaly.

Because of their height differences, children diagnosed with Sotos syndrome often have coordination problems that extend into adulthood if not treated at an early age.

While many people with Sotos have learning problems that can vary widely in severity, not all do. The amount of trouble someone has learning tends to stay the same over the course of their life.

How is Sotos syndrome diagnosed?

Diagnosing Sotos syndrome can be challenging because it shares the same symptoms as other common conditions. Your healthcare provider will begin the diagnosis by physically examining your child to look for symptoms of the condition. If indicated, a genetic test will follow the physical examination, where your healthcare provider will take a small sample of blood from your child to look for mutations on the NSD1 gene. If the results show a mutation on the NSD1 gene, your healthcare provider will diagnose your child with the condition. This usually happens during infancy or early childhood.

How is Sotos syndrome treated?

Treatment for Sotos syndrome varies based on the severity of the diagnosis and aims to alleviate symptoms of the condition. Treatment for Sotos syndrome includes:

• Educational support (special education program).
• Participating in therapy (behavioral, physical, speech).
• Taking medications to manage symptoms (ADHD, anxiety).
• Using hearing aids.
• Wearing a back brace or undergoing surgery for scoliosis.
• Wearing glasses.

Early intervention for developmental delays and other symptoms related to Sotos syndrome generally helps children reach their full potential.

How can I reduce my risk of having a child with Sotos syndrome?

There is no way to prevent most cases of Sotos syndrome. It’s a rare condition caused by a genetic mutation that happens unexpectedly. If you have Sotos syndrome, or if you plan on becoming pregnant, talk with your healthcare provider about genetic testing to assess your risk of having a child with a genetic condition.

What can I expect if I have a child with Sotos syndrome?

Sotos syndrome is a lifelong condition and there is no cure. The condition often times does not have any life-threatening side effects and the outlook for a child diagnosed with Sotos syndrome is positive, with a normal life expectancy. Your child may experience symptoms from the genetic condition, but treatments and therapies are available to minimize them as much as possible. Your child’s healthcare provider will work with you to address any concerns.

When should I see my child’s healthcare provider?

You should visit your child’s healthcare provider if you notice your child:

• Doesn't respond to simple verbal commands or has trouble hearing.
• Has behavioral problems that affect how they learn in school.
• Has trouble seeing clearly or squints frequently when looking at something.
• Misses developmental milestones.

When should I go to ER?

If your child has Sotos syndrome and experiences a seizure, you should visit the emergency room. Seizures are a severe complication of Sotos syndrome. A seizure occurs when your child:

• Loses consciousness temporarily.
• Moves their arms and legs uncontrollably.
• Shows signs of confusion, anxiety or fear.

Seizures normally last between 30 seconds and two minutes. Any seizure lasting more than five minutes is a medical emergency, so call 911 immediately.

What questions should I ask my doctor?

• What happens if my child misses developmental milestones?
• How do I prevent my child from getting hurt if they have coordination difficulties?
• Does my child need to see a specialist for any side effects of their diagnosis?

What’s the difference between Sotos syndrome and autism spectrum disorder?

Sotos syndrome and autism spectrum disorder (ASD) are different conditions. But they both have some of the same symptoms, which could lead to a misdiagnosis. Sotos syndrome is a genetic condition caused by a gene mutation and ASD is a neurodevelopmental condition, which many times has an unknown cause. However, people with Sotos syndrome have a higher chance of developing ASD than people without Sotos syndrome.

Both Sotos syndrome and autism spectrum disorder share some similar symptoms, including:

• Cognitive differences (intellectual disabilities).
• Delayed language development.
• Delayed motor skills and coordination.
• Difficulty adjusting to social situations.
• Difficulty paying attention.
• Patterns of behavior and routines.

The main difference between the two conditions is that Sotos syndrome also affects growth whereas autism spectrum disorder doesn’t. Children diagnosed with Sotos syndrome grow more and faster than their peers of the same age, are taller and have distinct facial characteristics.

A note from Cleveland Clinic

While a rare genetic diagnosis for your child may be overwhelming, Sotos syndrome is most often not a life-threatening condition. Your child will be able to reach their full potential with love and support from their caregivers. If you plan on becoming pregnant, discuss genetic testing with your healthcare provider to assess your risks of having a child with a genetic condition.