Hanhart syndrome

The exact underlying cause of Hanhart syndrome is currently unknown. However, researchers suspect that there may be genetic and/or environmental factors that contribute to the development of the condition. To date, no specific disease-causing genes have been identified. Possible environmental factors including:

• Exposure of the pregnant mother to radiation, teratogenic medications, or hypothermia
• Trauma or disrupted blood flow to the baby in the womb
• Chorionic villus sampling procedures (when performed too early in the pregnancy)

A diagnosis of Hanhart syndrome is typically made based on the presence of characteristic signs and symptoms. In some cases, the diagnosis may be suspected before birth if concerning features are seen on ultrasound.

Hanhart syndrome is a rare condition that primarily affects the craniofacial region and the limbs (arms and legs). People affected by this condition are often born with a short, incompletely developed tongue; absent or partially missing fingers and/or toes; abnormalities of the arms and/or legs; and an extremely small jaw. The severity of these physical abnormalities varies greatly among affected people, and children with this condition often have some, but not all, of the symptoms. The cause of Hanhart syndrome is not fully understood. Treatment depends on the signs and symptoms present in each person.

The long-term outlook (prognosis) for people with Hanhart syndrome varies and largely depends on the signs and symptoms present in each person. Severe associated craniofacial abnormalities can be life-threatening and may impair breathing, eating, and/or swallowing. However, early diagnosis and treatment can improve survival and quality of life for affected people.

Because Hanhart syndrome affects many different systems of the body, medical management is often provided by a team of doctors and other healthcare professionals. Treatment for this condition varies because it depends on the signs and symptoms present in each person. For example, limb and/or craniofacial abnormalities may be treated with surgery and/or prostheses. Affected children may also need speech therapy, physical therapy, and/or occupational therapy.