Welcome to the Rare Classroom, a new series from Patient Worthy. Rare Classroom is designed for the curious reader who wants to get informed on some of the rarest, most mysterious diseases and conditions. There are thousands of rare diseases out there, but only a very small number of them have viable treatments and regularly make the news. This series is an opportunity to learn the basics about some of the diseases that almost no one hears much about or that we otherwise haven’t been able to report on very often.

Eyes front and ears open. Class is now in session.

The disease that we will be learning about today is:

Apert Syndrome

Sometimes called acrocephalo-syndactyly type 1.

What is Apert Syndrome?

• Apert syndrome is a congenital disorder distinguished by deformations impacting the skull and extremities
• It’s a form of acrocephalosyndactyly and branchial arch syndrome
  • The branchial arch is the precursor of the upper and lower jaw
• Apert syndrome produces distinctive physical characteristics which allow for diagnosis to be relatively easy compared to other genetic disorders
  • CT scans or skull x-ray can also aid in diagnosis, and molecular genetic testing can be used as final confirmation
• The disease is named after Eugéne Apert, a French physician who described the disease from nine cases in 1906
• Prevalence is around 1 in 70,000 births

How Do You Get It?

• Apert syndrome may be passed along in an autosomal dominant fashion, but an exact cause hasn’t been identified
  • A child of someone with the disorder has a 50% chance of inheriting the disease
  • Nearly all cases are sporadic, meaning they aren’t inherited and are instead the result of a random, sporadic mutation
• Males and females are impacted at equal rates
• A mutation impacting the FGFR2 gene is implicated in two thirds of cases
• One risk factor for Apert syndrome is an older father

What Are the Symptoms?

• Symptoms of Apert syndrome include:
  • Craniosynostosis, in which the infant’s skull sutures close prematurely
  • Syndactyly, a deformation of the feet and/or hands
    • Common types include:
      • Type 1 (“spade hand”) – Index, middle, and ring fingers are fused together.
      • Type 2 (“spoon hand”) – More severe; the thumb is also involved, fusing to the index finger
      • Type 3 (“hoof hand”) – Most severe form, with all digits fused together, connected with a long, conjoined fingernail
  • High arched palate
  • Crowded teeth
  • Narrow palate
  • Pseudomandibular prognathism

How Is It Treated?

• Surgery is the critical component of treatment in Apert syndrome
• For craniosynostosis, surgery is vital to prevent the sutures from closing prematurely
• There is no standard approach for the management of syndactyly, primarily due to the great degree of variation among cases
  • Surgery focuses on releasing the fused digits, with the more complex, type III form being the most challenging to treat
  • As the hands grow and develop, continued operations may be necessary over time

Where Can I Learn More???

• Check out our cornerstone on this disease here.