Noonan Syndrome: A Guide for Parents

Noonan syndrome is a genetic condition diagnosed in 1 in 1000-2500 live births. It can cause a variety of issues that can affect the heart, growth and learning. Noonan syndrome can be inherited from a parent, or it can be a random genetic difference that the baby is born with. Children with Noonan syndrome often need to see multiple specialists, including a pediatric endocrinologist and cardiologist. Below are several endocrine conditions that can be seen in children with Noonan syndrome.

Common Endocrine Problems in Noonan Syndrome:

· Short stature: Children with Noonan Syndrome often are shorter than their peers. Sometimes, they are not producing enough growth hormone. Oftentimes, the child will need to be evaluated by a pediatric endocrinologist and undergo a diagnostic work up to determine why they are not growing well. Growth hormone can be used to treat short stature in patients with Noonan syndrome.

· Hypothyroidism: This means the thyroid gland doesn’t make enough thyroid hormone. Some signs of hypothyroidism include feeling tired or cold easily, constipation, dry skin and poor growth. Children with Noonan syndrome should have their thyroid levels checked regularly. If their levels are low, they may be prescribed a medication called levothyroxine to increase their levels of thyroid hormone.

· Late puberty: For girls, this is defined as lack of breast developed by age 13 or not having a period by age 16. For boys, this is defined as not having testicular development by age 14. A pediatric endocrinologist can run additional tests to figure out why the child hasn’t started puberty and prescribe medications if necessary.