Jansen-de Vries syndrome

Jansen-de Vries syndrome is a developmental disorder that affects many parts of the body. Features of this condition include unique facial features, intellectual disability, certain personality characteristics, behavioral changes, and gastrointestinal problems. 

The signs and symptoms of Jansen-de Vries syndrome typically begin soon after birth. Affected infants often have low muscle tone (hypotonia) and feeding difficulties. Children with this disorder are often slow to develop speech and language skills, They may also be slow to acquire motor skills, such as standing or walking. People with Jansen-de Vries syndrome also tend to have intellectual disability, which can range from mild to severe.  

Additional features seen in people with Jansen-de Vries syndrome may include short stature, small hands and feet, and differences in facial features. The facial features that are common in people with this condition include a broad forehead, thin upper lip, low-set ears that are rotated backwards, and downturned corners of the mouth. 

Gastrointestinal problems, such as constipation, are also common in people with Jansen-de Vries syndrome. Many affected individuals experience recurrent episodes of nausea and vomiting (cyclic vomiting).

Though people with Jansen-de Vries syndrome tend to be very social with outgoing and friendly personalities, affected individuals may experience behavioral differences, such as anxiety disorders and attention-deficit hyperactivity disorder. Some people with Jansen-de Vries syndrome have autism-spectrum disorder, a developmental disorder that affects communication and social skills.

Other signs and symptoms of Jansen-de Vries syndrome include vision problems, an increased sensitivity to sound (hyperacusis), and a higher-than-normal pain threshold. Less commonly, people with Jansen-de Vries syndrome can have congenital heart defects. These may include openings in the wall (septum) that separates the upper or lower chambers of the heart (atrial or ventricular septal defects).