Ellis-van Creveld syndrome

Ellis-van Creveld syndrome (EVC), also known as chondroectodermal dysplasia, is a rare genetic disorder that affects bone growth, leading to short stature and polydactyly, among other symptoms. It is characterized by a combination of postaxial polydactyly, congenital heart defects, nail dysplasia, and oral manifestations including fusion of the upper lip to the gum. This condition was first described in 1940 by Richard W.B. Ellis and Simon van Creveld, following their observation of the syndrome in Amish populations.

Etiology and Genetics

Ellis-van Creveld syndrome is inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the mutated gene, one from each parent, to be affected by the condition. The genes implicated in EVC are EVC and EVC2, located on chromosome 4p16. Mutations in either of these genes disrupt the normal development of bones, teeth, and other tissues, leading to the manifestations of the syndrome.

Clinical Features

The clinical presentation of Ellis-van Creveld syndrome can vary significantly among affected individuals. However, common features include:

• Short stature: Most individuals with EVC have disproportionately short limbs.
• Polydactyly: The presence of extra fingers or toes is a hallmark of the syndrome.
• Congenital heart defects: Approximately half of the individuals with EVC have heart anomalies, which can be life-threatening.
• Nail dysplasia: Abnormalities in nail growth and appearance.
• Oral manifestations: These may include a cleft palate or a partial cleft, fusion of the upper lip to the gum, and dental anomalies.

Diagnosis

Diagnosis of Ellis-van Creveld syndrome is primarily based on clinical observation and family history. Genetic testing can confirm mutations in the EVC or EVC2 genes, providing a definitive diagnosis. Prenatal diagnosis is possible through genetic testing if there is a known family history of the condition.

Treatment

There is no cure for Ellis-van Creveld syndrome, and treatment focuses on managing symptoms and improving quality of life. Surgical interventions may be necessary to correct congenital heart defects or polydactyly. Dental and orthodontic treatments can address oral and dental anomalies. Regular follow-up with a multidisciplinary team is essential to monitor and treat the various aspects of the syndrome.

Prognosis

The prognosis for individuals with Ellis-van Creveld syndrome varies depending on the severity of symptoms, particularly the presence and severity of congenital heart defects. With appropriate medical and surgical management, many individuals with EVC can lead active lives.

Epidemiology

Ellis-van Creveld syndrome is rare, with a higher prevalence in certain populations, such as the Old Order Amish of Pennsylvania, due to the founder effect. The incidence is estimated to be 1 in 60,000 to 1 in 200,000 live births worldwide.

See Also

• Dwarfism
• Polydactyly
• Congenital heart defect