Medical Information

HEALTH & SOCIAL ISSUES

The following are guides to some of the different and critical medical issues that you should be aware of, as well as resources for learning more about each of them.

FEEDING ISSUES

Some children with Noonan Syndrome will have feeding difficulties. They can be very difficult for parents but the good news is that they often get better and improve with time.

Children with Noonan Syndrome may have some of the following feeding problems:

Poor or slow sucking as newborns (this may include a period of tube feeding)
Lack of interest in eating or an aversion for eating (this may follow prolonged tube feeding)
Difficulty in progressing to solid food, particularly of this contains lumps
Poor chewing, which means meals take a long time
Vomiting and/or retching which appears to have no definable cause
A sensitivity to particular food

For more resources related to feeding tubes you can visit www.feedingtubeawareness.org.

GROWTH ISSUES

Approximately 50% to 70% of those with Noonan syndrome have short stature. The MAGIC Foundation is the global leader in endocrine health, advocacy, education, and support.

ORTHOPAEDIC ISSUES

More information on orthopedic issues associated with Noonan Syndrome can be found here.

BREATHING ISSUES

There have been some reported cases of breathing issues in babies and children with Noonan syndrome (NS). Some of these breathing issues may include laryngomalacia, tracheomalacia, subglottic stenosis and other issues with floppiness in the airway.

Cincinnati Children's Hospital has a world-renown Aerodigestive and Sleep Center that can help in these matters. They can even review your child's transcripts if you live far away, and help your doctors find solutions.

For details, please visit Cincinatti Children's Hospital.

BLEEDING ISSUES

It is important to note that some people with Noonan syndrome (NS) have significant bleeding disorders. Please read the following articles on NS and bleeding disorders before any procedure and/or surgery is performed.

Hemostatic Abnormalities in Noonan Syndrome

Bleeding Disorders in Noonan Syndrome

Imbalance of plasminogen activator inhibitor type-1 (PAI-1) and

tissueplasminogen activator (t-PA) activity in patients with Noonan Syndrome

CARDIOVASCULAR ISSUES

The following information is from the article titled Noonan Syndrome: Clinical Features and Management Guidelines:

More than 80% of patients with NS have an abnormality of the cardiovascular system. PVS is the most common. The valve may be dysplastic in 25% to 35% of those with PVS64,–,66 and is often associated with an ASD. Isolated ASDs and partial atrioventricular canal defects are also relatively common. A broad spectrum of cardiac abnormalities has been reported, as noted in Table 5. Approximately 50% of patients with NS have an unusual electrocardiographic pattern characterized by left-axis deviation, an abnormal R/S ratio over the left precordial leads, and an abnormal Q wave. Many patients have mild PVS that requires only periodic reevaluation. If the PVS is or becomes clinically significant, initial treatment is usually pulmonary balloon valvuloplasty, but it may be unsuccessful if the valve is dysplastic. With severe dysplasia, a pulmonary valvectomy or pulmonary homograft may be needed in childhood. The other cardiac defects can be treated in the standard ways.

HCM is present in ∼20% of patients with NS overall but is particularly frequent with RAF1 mutations, 31, 32 and it is variable in severity and natural history. In some infants with HCM the condition resolves, whereas in others it becomes rapidly progressive and may have a fatal outcome. Others develop HCM after infancy. The course may be stable or progressive, or it may improve. Management is similar to that for any patient with HCM and may include the use of β-blocker medications or surgical myomectomy to reduce outflow obstruction.

It is important for adults with NS to have lifetime cardiac follow-up. Left-sided obstructive lesions may develop in adulthood. Pulmonary valve insufficiency and right ventricular dysfunction are potential problems after earlier pulmonary valve surgery. Cardiac arrhythmias have been rare in the limited reports available about long-term follow-up of adults.

RASopathies and the Heart

A webinar by Dr. Bruce Gelb on Noonan syndrome and the heart.

SCHOOL ISSUES

The Noonan Syndrome Foundation recognizes that parents and young adults may face difficulties regarding educational and school-related issues. Follow this link to a guide about Attention & Executive Function Concerns in Children with Noonan Syndrome.

GENETIC TESTING

The National Institutes of Health's Library on Genetic Research and testing related to Noonan Syndrome can be found here.