Noonan syndrome is a rare genetic condition that is present at birth. Most people affected by the syndrome can lead a normal life. You can find more information below.
What is Noonan syndrome?
Noonan syndrome is a genetic disease that prevents normal development in various parts of the body . A person can be affected by Noonan syndrome in a wide variety of ways. These; unusual facial features, short stature, heart defects, other physical problems, and possible developmental delays.
Noonan syndrome is caused by a genetic mutation and occurs when the child inherits a copy of the affected gene from one parent (dominant inheritance). However, the disease can also occur with a spontaneous mutation, so in this case it has nothing to do with family health history.
Treatment of Noonan syndrome focuses on controlling the symptoms and complications of the disease. For example, growth hormone may be used to treat short stature in some people with this genetic syndrome.
Noonan syndrome causes and risk factors
Noonan syndrome is caused by a genetic mutation. These mutations can occur in more than one gene. Defects in these genes result in the production of proteins that are constantly active. Because these genes play a role in the formation of many tissues in the body, this constant activation of proteins disrupts the normal process of cell growth and division.
Mutations that cause Noonan syndrome may include:
- Inherited from parents: Children with a parent with Noonan syndrome who carry the defective gene (autosomal dominant) have a 50 percent chance of developing the disorder.
- Random mutation: Noonan syndrome may develop due to a new genetic mutation in children who do not have a genetic predisposition to the disease.
Who is at risk?
A parent with the disease has a 50 percent chance of passing the defective gene on to their child. The child who inherits the defective gene may have fewer or more symptoms than the affected parent.
Noonan syndrome symptoms
Noonan syndrome develops before birth. Sometimes the disease is diagnosed right away, but some children with mild symptoms may not be diagnosed until adulthood.
Children with this genetic condition often have medical problems such as heart defects, bleeding (clotting) abnormalities, and bone deformities. They are usually shorter and their muscle tone (the tension that creates the space needed for the muscle to contract) may be low.
Individuals with this genetic disease may also have a distinctive appearance, including the following symptoms:
- a characteristic facial appearance
- congenital heart defects
- a wide or thick neck
- Minor eye problems such as strabismus in up to 95 percent of individuals
- Bleeding problems such as abnormal bleeding or a history of bruising
- An unusual chest shape with a wide gap
- varying degrees of developmental delay
- In males, undescended testicles (Cryptorchidism is the condition in which the testicles cannot reach where they should be during the developmental process of the male child in the mother’s womb.)
Some children with Noonan syndrome may experience intellectual disability, clumsiness, or behavioral problems such as irritability. As babies with Noonan syndrome get older, their symptoms may change and may become less noticeable as they reach adulthood.
When should you see a doctor?
The symptoms of Noonan syndrome can be mild. If you suspect that you or your child may have a disorder, it is always useful to consult a doctor. You or your child may be referred to a geneticist or a cardiologist.
Diagnosis of Noonan syndrome
The diagnosis of Noonan syndrome is usually made after the doctor observes some key symptoms, but this can be difficult. Because some features show mild symptoms and are difficult to identify. In some cases, Noonan syndrome is not diagnosed until adulthood because symptoms may not be noticed or absent until adulthood.
Molecular genetic testing can help confirm a diagnosis. If there is evidence of heart problems, a doctor who specializes in heart conditions (cardiologist) can assess the type and severity.
Noonan syndrome treatment
Although there is no way to repair the gene changes that cause Noonan syndrome, treatments can help minimize its effects. The earlier the diagnosis is made and the treatment started, the greater the benefits.
Treatment of symptoms and complications that occur with Noonan syndrome depends on the type and severity of the disease. Most of the health and physical problems associated with this syndrome are treated with the same methods for anyone with a similar health condition. However, when the presence of the syndrome is considered together with the treatment process, a coordinated team work is required for many other problems of this disorder.
- Heart treatment: Some medications can be effective in treating certain heart problems. If there is a problem with the valves of the heart, surgery may be needed. The doctor may also recommend periodic evaluation of heart function.
- Treating low growth rate: Height should be measured three times a year up to 3 years of age to ensure growth. To assess nutrition, the doctor will likely order blood tests. If your child’s growth hormone levels are insufficient, growth hormone therapy may be a treatment option.
- Elimination of learning difficulties: For delays in early childhood development, information about infant stimulation programs should be obtained from the doctor. Physical and speech therapies can be helpful in addressing a variety of potential problems. In some cases, special education or personalized teaching strategies may be appropriate.
- Vision and hearing treatments: Eye examinations are recommended at least every two years. Most eye problems can be treated with glasses alone. Some conditions, such as cataracts, may require surgical intervention. Hearing screenings are recommended annually and in childhood.
- Treatment for bleeding and bruising: If you have easy bruising or excessive bleeding, you should avoid medications that thin the blood, such as aspirin . In some cases, doctors may prescribe medications that help blood clot.
- Treatment of lymphatic problems: Lymphatic (the pattern that produces lymph fluid and transfers it from the tissues to the circulatory system) problems can occur in many forms and may not require treatment. If treatment is needed, the doctor can recommend appropriate measures.
- Treatment of genital problems: If one or both testicles have not moved into the proper position in the first few months of life, surgery may be required.
Your doctor may recommend other evaluations and regular follow-up care depending on certain issues, such as regular dental care. Children, adolescents and adults should continue to be evaluated by healthcare professionals on an ongoing and periodic basis.
Can Noonan syndrome be prevented?
There is no known way to prevent it, as some cases occur spontaneously. However, if you have a family history of this syndrome, you can talk to your doctor about the benefits of genetic counseling before having children. Noonan syndrome can be detected by molecular genetic testing.
It is thought that if the syndrome is detected early, continued and comprehensive care can reduce some of its complications, such as heart disease.
Noonan syndrome complications
Complications that may require special attention may occur with this genetic syndrome, including the following:
- Developmental delays: If your child is developmentally affected, they may have difficulties socially and spatially. Sometimes the developmental challenges are so significant that they require a specific plan to meet the child’s learning and educational needs.
- Bleeding and bruising: Sometimes the excessive bleeding condition common in Noonan syndrome is not discovered until it occurs during a person’s dental treatments, at any stage of surgery, or if they experience excessive bleeding.
- Lymphatic complications: These complications usually involve excess fluid stored in various parts of the body. Sometimes this fluid can collect in the space around the heart and lungs.
- Urinary tract complications: Structural abnormalities in the kidneys can increase the risk of urinary tract infections.
- Fertility issues: Men can have low sperm count and other fertility issues due to undescended testicles or testicles that don’t work properly.
- Increased risk of cancer: There may be an increased risk of developing certain types of cancer, such as leukemia or certain types of tumors.