Shprintzen-Goldberg Syndrome

Shprintzen-Goldberg syndrome is a rare genetic disorder that affects multiple parts of the body, causing distinctive skull and facial features, skeletal problems, and developmental challenges that vary widely from person to person.

Table of contents

• What is Shprintzen-Goldberg Syndrome?
• Other Names for This Condition
• Medical Classification Codes
• How Common is This Condition?
• What Causes Shprintzen-Goldberg Syndrome?
• How is the Condition Inherited?
• Signs and Symptoms
• Related Conditions
• Diagnosis
• Treatment and Management

What is Shprintzen-Goldberg Syndrome?

Shprintzen-Goldberg syndrome is a rare genetic disorder that affects several parts of the body^[1]. The condition was first described as a distinct medical condition in 1982 by Shprintzen and Goldberg^[6].

People with this syndrome have a combination of distinctive facial features and skeletal and neurological problems^[2]. A key feature is craniosynostosis, which means the skull bones fuse together too early during development before birth. This early fusion prevents the skull from growing normally^[1].

The condition affects many body systems, including the skeleton, brain, heart, and digestive system. The symptoms can range from mild to severe, and they vary widely from person to person^[1].

Other Names for This Condition

Marfanoid-craniosynostosis syndrome, Shprintzen-Goldberg craniosynostosis syndrome, SGS

Medical Classification Codes

Q87.8
C537328

How Common is This Condition?

Shprintzen-Goldberg syndrome is very rare. Scientists are not sure exactly how many people have the disorder. There are fewer than 50 cases described in medical literature^[1]. Another source suggests approximately 75 cases have been documented since the condition was first described in 1982^[6].

The true number of affected people may be higher because the condition is sometimes misdiagnosed. Experts often confuse it with other similar conditions, particularly Marfan syndrome and Loeys-Dietz syndrome, which makes it difficult to know how many people are actually affected^[1].

What Causes Shprintzen-Goldberg Syndrome?

Most cases of Shprintzen-Goldberg syndrome are caused by changes in the SKI gene^[1]. This gene provides instructions for making a protein that regulates an important signaling pathway in the body called the transforming growth factor beta (TGF-β) pathway^[2].

The TGF-β pathway controls many processes, including how cells grow and divide, how they mature to carry out special functions, how they move, and even how they die^[2]. The SKI protein normally works by attaching to certain proteins in this pathway and blocking the TGF-β signaling^[2].

When the SKI gene has a mutation, the altered protein can no longer properly attach to proteins in the TGF-β pathway and block signaling. As a result, the pathway becomes abnormally active. This excess TGF-β signaling disrupts the normal development of many body systems, including the bones and brain, resulting in the wide range of symptoms seen in Shprintzen-Goldberg syndrome^[2].

The SKI protein is found in many different types of cells throughout the body and appears to play a role in the development of many tissues, including the skull, other bones, skin, and brain^[2]. This explains why the syndrome affects so many different parts of the body.

Not all cases of Shprintzen-Goldberg syndrome involve a mutation in the SKI gene. In some cases, other genes may be involved, and scientists do not currently understand what else causes the condition^[1].

How is the Condition Inherited?

Most cases of Shprintzen-Goldberg syndrome are not inherited from parents. The gene mutation usually occurs spontaneously, which means it happens randomly during development before birth^[1]. Most people with the disorder have no family history of it^[1].

The condition is described as autosomal dominant^[6]. This means that if the mutation is present, only one copy of the mutated gene is needed to cause the condition. In rare cases, parents can pass the condition on to their children. When it is inherited, you only need to inherit one copy of the mutated gene from one parent who carries the mutation^[1].

Some cases have occurred in siblings born to unaffected parents, which suggests the possibility of germline mosaicism. This means that one parent may have the mutation in their egg or sperm cells but not in other cells of their body^[4].

Signs and Symptoms

Signs and symptoms of Shprintzen-Goldberg syndrome vary widely. They can range from mild to severe, and they may affect several different body parts^[1].

Skull and Facial Features

When skull bones fuse too early (craniosynostosis), this can cause several distinctive facial and head features^[1]:

• Long, narrow head
• Widely spaced eyes that may protrude (stick out) or slant downward
• High, narrow palate (roof of the mouth)
• High, prominent forehead
• Small lower jaw
• Low-set ears that may be rotated backward

Skeletal Problems

People with Shprintzen-Goldberg syndrome are often said to have a marfanoid habitus, which means their bodies resemble those of people with Marfan syndrome^[2]. Skeletal abnormalities may include^[1]:

• Long arms and legs
• Long, skinny fingers (a condition called arachnodactyly)
• Ability to move the joints beyond the normal range of motion (joint hypermobility)
• Fingers that are permanently bent (called camptodactyly)
• Clubfoot
• Chest that sticks out or appears to sink in (pectus carinatum or pectus excavatum)
• Curved spine (scoliosis)

Neurological Features

People with Shprintzen-Goldberg syndrome often have delayed development and mild to moderate intellectual disability^[2]. Intellectual disability is more likely to occur in Shprintzen-Goldberg syndrome than in similar conditions like Marfan syndrome or Loeys-Dietz syndrome^[2].

Brain abnormalities may also occur, such as excess fluid in the brain (a condition called hydrocephalus)^[1].

Heart and Blood Vessel Problems

Heart abnormalities are less common and usually less severe in Shprintzen-Goldberg syndrome compared to Marfan syndrome and Loeys-Dietz syndrome^[1]. However, some cardiovascular problems may include^[3]:

• Mitral valve prolapse
• Mitral and aortic valve regurgitation
• Aortic root enlargement

Other Features

Additional symptoms that some people with Shprintzen-Goldberg syndrome may experience include^[1]:

• Gastrointestinal (digestive) problems such as constipation or gastroparesis (delayed emptying of the stomach)
• Abdominal or umbilical hernias
• Skin that seems almost see-through and bruises easily
• Weak muscle tone in infancy (called hypotonia)
• Vision problems such as myopia (nearsightedness)

Related Conditions

Shprintzen-Goldberg syndrome has signs and symptoms similar to those of Marfan syndrome and Loeys-Dietz syndrome. However, these three disorders are caused by different genetic mutations^[1].

The key differences are that people with Shprintzen-Goldberg syndrome are more likely to have an intellectual disability and are less likely to have heart abnormalities compared to people with Marfan syndrome or Loeys-Dietz syndrome^[1]. Heart abnormalities are more common and usually more severe in Marfan syndrome and Loeys-Dietz syndrome^[2].

Diagnosis

Formal diagnostic criteria for Shprintzen-Goldberg syndrome have not been established^[4]. The diagnosis is established when a person has a combination of the typical clinical features and a heterozygous pathogenic variant in the SKI gene identified by molecular genetic testing^[4].

Healthcare providers should suspect Shprintzen-Goldberg syndrome in individuals with a combination of craniosynostosis, distinctive facial features, skeletal abnormalities, and neurological problems^[4].

Treatment and Management

There is no cure for Shprintzen-Goldberg syndrome, but various treatments can help manage the symptoms and improve quality of life.

Treatment of Symptoms

Management strategies include^[4]:

• Early intervention for developmental delay with placement in special education programs
• Standard management of cleft palate and craniosynostosis
• Surgical fixation may be necessary for cervical spine instability
• Routine management for scoliosis
• Surgical correction for pectus excavatum is rarely indicated
• Physiotherapy for joint contractures
• Clubfoot deformity may require surgical correction
• If aortic dilatation is present, treatment with beta-adrenergic blockers or other medications should be considered to reduce stress on the heart
• Surgical intervention for aneurysms may be indicated
• Treatment of myopia as recommended by an ophthalmologist
• Surgical repair of abdominal hernias as indicated

Prevention and Surveillance

Preventive measures include^[4]:

• Subacute bacterial endocarditis prophylaxis is recommended for dental work or other procedures for individuals with cardiac complications

Regular monitoring should include^[4]:

• Developmental assessment with each visit
• Cervical spine evaluation and clinical evaluation for scoliosis as recommended by an orthopedist
• Imaging as recommended by a cardiologist familiar with this condition
• Ophthalmology exams as recommended by an ophthalmologist

Activities to Avoid

People with Shprintzen-Goldberg syndrome should avoid^[4]:

• Contact sports
• Use of agents that stimulate the cardiovascular system
• Activities that may lead to joint pain or injury

Genetic Counseling and Testing

Once a SKI pathogenic variant has been identified in an affected family member, prenatal testing for a pregnancy at increased risk and preimplantation genetic testing are possible^[4].