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Noonan syndrome and congenital heart conditionsNNoonan syndrome and congenital heart conditionsNoonan Syndrome and Congenital Heart ConditionsEnglishCardiologyChild (0-12 years);Teen (13-18 years)HeartCardiovascular systemConditions and diseasesAdult (19+)NA2021-05-10T04:00:00Z9.9000000000000052.20000000000001192.00000000000Health (A-Z) - ConditionsHealth A-Z<p>Noonan syndrome is a genetic condition. Learn about the symptoms and diagnosis of Noonan syndrome and the heart conditions associated with the condition.</p><h2>What is Noonan syndrome?</h2><p>Noonan syndrome is a genetic condition that occurs in about 1 in every 1000–2500 children. It is equally present in both males and females and in all parts of the world. </p><h2> Key points </h2><ul><li>Noonan syndrome is a relatively common genetic condition. It is most often diagnosed in childhood but can be diagnosed at any age.</li><li>In 60% of cases, Noonan syndrome is caused by a genetic change (variant) which occurs for the first time in the child. However, it can also be inherited from a parent.</li><li>Every child with Noonan syndrome is different, individuals with Noonan syndrome can have many or few physical or developmental differences. About 80% of cases of Noonan syndrome involve a heart condition.</li><li>There is currently no single treatment for Noonan syndrome, but it is often possible to successfully manage several aspects of the condition. </li></ul><h2>Signs and symptoms of Noonan syndrome</h2><p>Noonan syndrome can affect different parts of the body. Individuals with Noonan syndrome may have only a few or many of the physical or developmental differences listed below:</p><h3>Face and neck</h3><ul class="akh-steps"><li> <figure> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Eyes.jpg" alt="Close up of widely-spaced eyes and close up of eyes with ptosis" /> <figcaption>Top: Widely-spaced eyes. Bottom: Eyes with ptosis (droopy eyelid).</figcaption></figure> <p>Widely-spaced eyes or abnormalities of the eyes and eyelids that may or may not affect vision (e.g., <a href="/article?contentid=1032&language=english">ptosis</a>)</p></li><li> <figure> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Nose.jpg" alt="Close up of flattened nasal bridge between the eyes" /> </figure> <p>Flattened nasal bridge</p></li><li> <figure> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Ear.jpg" alt="Ears that are oval-shaped and sit lower on the head" /> </figure> <p>Oval-shaped, low-set ears</p></li><li> <figure><img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Nuchal.jpg" alt="Child with nuchal fold at back of neck" /> </figure> <p>Increased nuchal fold (area at the nape or back of the neck)</p></li><li> <figure><img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Neck.jpg" alt="Child with normal neck compared to child with broad or webbed neck" /><figcaption>Top: A normal neck. Bottom: Broad neck with excess skin.</figcaption></figure> <p>Broad neck with excess skin (webbed neck)</p></li></ul><h3>Skeleton and limbs</h3><ul class="akh-steps"><li> <figure> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Scoliosis.jpg" alt="Orange dotted line showing the curve in a child's spine" /> <figcaption>The orange dotted line represents the curve in the child's spine (scoliosis). The solid orange line shows where the child's spine should be straight. </figcaption></figure> <p>Abnormal side-to-side curvature of the spine (<a href="/article?contentid=2006&language=english">scoliosis</a>).</p></li><li> <figure> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Chest.jpg" alt="Child on the left with sunken chest and child on the right with protruding chest" /> <figcaption>On the left is an example of a sunken chest. On the right is an example of a protruding chest.</figcaption></figure> <p>Sunken chest (pectus excavatum) or a protruding chest (pectus carinatum)</p></li><li>Short stature</li><li>Swollen hands and feet (lymphedema) usually seen in infants</li></ul><h3>Brain</h3><ul><li>A spectrum of learning difficulties</li><li>Impaired hearing </li><li>Delayed milestones</li></ul><h3>Genitals</h3><ul><li> <a href="/article?contentid=884&language=english">Undescended testicles</a></li><li>Delayed puberty onset</li></ul><h3>Feeding and nutrition</h3><ul><li>Feeding difficulties in infants and small children</li></ul><h3>Blood</h3><ul><li>Increased tendency to bleed<br></li><li>A rare but increased risk of some types of cancer</li></ul><h2>Causes of Noonan syndrome</h2><p>Noonan syndrome is caused by one of several <a href="/body/interactive?module=genetics">genes</a> that play a key role in the normal functioning of cells. At least 12 genes have currently been associated with Noonan syndrome.</p><p>In most cases (60%), Noonan syndrome is caused by a genetic change (variant) that occurs for the first time (de novo) in the child. </p> <figure class="asset-c-80"> <span class="asset-image-title">De novo inheritance</span> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_de_novo_mutation_EN.jpg" alt="Baby inherits one copy of gene from each unaffected parent with spontaneous new gene variant causing baby to be affected with Noonan syndrome." /></figure> <p>Noonan syndrome can also be inherited from a parent. Most cases of inherited Noonan syndrome are inherited in an autosomal dominant manner. This means that if a parent has Noonan syndrome, there is a 50% chance in each pregnancy to have a child with Noonan syndrome. </p> <figure class="asset-c-80"> <span class="asset-image-title">Autosomal dominant inheritance</span> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_IMD_autosomal_dominant_EN.jpg" alt="Baby receives genes from affected parent and unaffected parent resulting in 50% chance of having Noonan syndrome." /></figure> <p>When the genetic change occurs de novo in the child, there is a less than 1% chance for the parents to have another child with Noonan syndrome.</p><p>There are a number of options for genetic testing either prior to or during a pregnancy for families that have an increased chance to have a child with Noonan syndrome. A <a href="/article?contentid=343&language=english">genetic counsellor</a> can help review these options. </p><h2>Diagnosis of Noonan syndrome</h2><p>The diagnosis of Noonan syndrome can be made either clinically or by genetic testing. A genetic change associated with Noonan is found in about 80-85% of individuals with Noonan syndrome. This means that a negative genetic test does not rule out the diagnosis. Genetic testing has important implications for genetic counselling and management.</p><h2>Treatment of Noonan syndrome</h2><p>There is currently no single treatment for Noonan syndrome, but it is often possible to successfully manage several aspects of the condition. Studies are underway for novel treatments.</p><p>Every child with Noonan syndrome is different and many go on to lead normal lives. Some children with Noonan syndrome can have delayed milestones or learning difficulties. However, when recognized early, they respond well to additional support. Children with Noonan syndrome typically also require regular follow-up by several medical specialties.</p><p>Patients with heart conditions may require a heart intervention or surgery, depending on the symptoms and severity of the condition. The treatment will depend on the specific heart defect. With pulmonary stenosis, the aim is to relieve the thickening of the valve and to make it easier for the blood to flow from the heart to the lungs. This can be achieved by a cardiac catheter (e.g. <a href="/article?contentid=1669&language=english">balloon dilation</a>) or, more frequently, by cardiac surgery (open-heart surgery). For information on treatment of hypertrophic cardiomyopathy, please see the article Hypertrophic cardiomyopathy. </p><h2>Heart conditions associated with Noonan syndrome</h2><p>About 80% of Noonan syndrome cases involve a heart condition. These conditions fall into two main categories: congenital heart disease (about 80% of cases involving a heart condition) and hypertrophic cardiomyopathy (about 20% of cases involving a heart condition).</p><h3>Congenital heart disease: Pulmonary stenosis</h3><p> <a href="/article?contentid=1619&language=english">Pulmonary valve stenosis</a> is the most common heart condition associated with Noonan syndrome, seen in up to 70% of cases. The pulmonary valve controls the blood flow from the heart to the pulmonary artery, which then leads to the lungs so the blood can get oxygen. Stenosis means that the valve is thick and its opening is narrower than normal, which makes it hard for the blood to flow through it. </p><p>In most cases this pulmonary valve narrowing is only mild and will not cause your child to have any symptoms or to require any intervention. Your child’s doctor might hear a murmur as they listen to your child’s chest. This is related to the turbulence of the blood as it crosses the thickened valve. </p><p>Less frequently, the pulmonary valve narrowing may be moderate or severe. These cases might require a cardiac intervention or a surgery.</p><h3>Congenital heart disease: Other heart defects</h3><p>Other heart defects may occur in Noonan syndrome patients, although this is less common. The majority of these defects are related to the abnormal formation of the walls that divide the left and the right sides of the heart. The atria are located in the upper part of the heart. The wall that separates the right and left atria is called the atrial septum. A defect (hole) in this wall is called an <a href="/article?contentid=1607&language=english">atrial septal defect (ASD)</a>. The majority of ASDs will produce no symptoms at first and might only be detected due to a murmur.</p> The ventricles (the pumping chambers) are located in the lower part of the heart. The wall that separates the right and left ventricles is called the ventricular septum. A defect in this wall is called a <a href="/article?contentid=1626&language=english">ventricular septal defect (VSD)</a>. Depending on the size of this hole, your child might have no symptoms at all or present with heart failure symptoms. This lesion will also produce a murmur that your child’s doctor may be able to hear with a stethoscope (auscultation). For more information on heart failure please see <a href="https://www.aboutkidshealth.ca/heartfailure">aboutkidshealth.ca/heartfailure</a>. <p></p><h3>Hypertrophic cardiomyopathy</h3><p>Hypertrophic cardiomyopathy is a condition in which the heart muscle becomes unusually thick. This can affect the amount of blood pumped to the body and cause heart rhythm problems. Many patients with this condition may not experience any symptoms at all, the only sign being a heart murmur on auscultation. Some patients may have shortness of breath, chest pain, dizziness, fainting, palpitations and, in rare cases, cardiac arrest. For more information please see the article <a href="/article?contentid=1629&language=english">Hypertrophic Cardiomyopathy</a>.</p><h2>Resources</h2><p><a href="https://www.teamnoonan.org/">Noonan Syndrome Foundation (USA)</a></p><p><a href="https://www.noonansyndrome.org.uk/">Noonan syndrome association (UK)</a></p><p><a href="https://noonansyndrome.com.au/support/">Noonan syndrome awareness association (Australia)</a></p><p><a href="http://ghr.nlm.nih.gov/condition/noonan-syndrome">Genetics Home Reference</a><br></p>
Syndrome de Noonan et les anomalies cardiaques congénitalesSSyndrome de Noonan et les anomalies cardiaques congénitalesNoonan Syndrome and Congenital Heart ConditionsFrenchCardiologyChild (0-12 years);Teen (13-18 years)HeartCardiovascular systemConditions and diseasesAdult (19+)NA2009-12-14T05:00:00Z11.000000000000042.0000000000000221.000000000000Flat ContentHealth A-Z<p>Environ 80 % des cas du syndrome de Noonan amènent une anomalie cardiaque.</p><p> Les enfants atteints du syndrome de Noonan ont souvent une anomalie cardiaque. </p><h2> À retenir </h2> <ul><li> Ce syndrome est une maladie génétique de cause inconnue marquée par certaines caractéristiques physiques.</li> <li> La majorité des cas du syndrome de Noonan impliquent une anomalie cardiaque.</li></ul>

 

 

 

 

Noonan syndrome and congenital heart conditions1637.00000000000Noonan syndrome and congenital heart conditionsNoonan Syndrome and Congenital Heart ConditionsNEnglishCardiologyChild (0-12 years);Teen (13-18 years)HeartCardiovascular systemConditions and diseasesAdult (19+)NA2021-05-10T04:00:00Z9.9000000000000052.20000000000001192.00000000000Health (A-Z) - ConditionsHealth A-Z<p>Noonan syndrome is a genetic condition. Learn about the symptoms and diagnosis of Noonan syndrome and the heart conditions associated with the condition.</p><h2>What is Noonan syndrome?</h2><p>Noonan syndrome is a genetic condition that occurs in about 1 in every 1000–2500 children. It is equally present in both males and females and in all parts of the world. </p><h2> Key points </h2><ul><li>Noonan syndrome is a relatively common genetic condition. It is most often diagnosed in childhood but can be diagnosed at any age.</li><li>In 60% of cases, Noonan syndrome is caused by a genetic change (variant) which occurs for the first time in the child. However, it can also be inherited from a parent.</li><li>Every child with Noonan syndrome is different, individuals with Noonan syndrome can have many or few physical or developmental differences. About 80% of cases of Noonan syndrome involve a heart condition.</li><li>There is currently no single treatment for Noonan syndrome, but it is often possible to successfully manage several aspects of the condition. </li></ul><h2>Signs and symptoms of Noonan syndrome</h2><p>Noonan syndrome can affect different parts of the body. Individuals with Noonan syndrome may have only a few or many of the physical or developmental differences listed below:</p><h3>Face and neck</h3><ul class="akh-steps"><li> <figure> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Eyes.jpg" alt="Close up of widely-spaced eyes and close up of eyes with ptosis" /> <figcaption>Top: Widely-spaced eyes. Bottom: Eyes with ptosis (droopy eyelid).</figcaption></figure> <p>Widely-spaced eyes or abnormalities of the eyes and eyelids that may or may not affect vision (e.g., <a href="/article?contentid=1032&language=english">ptosis</a>)</p></li><li> <figure> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Nose.jpg" alt="Close up of flattened nasal bridge between the eyes" /> </figure> <p>Flattened nasal bridge</p></li><li> <figure> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Ear.jpg" alt="Ears that are oval-shaped and sit lower on the head" /> </figure> <p>Oval-shaped, low-set ears</p></li><li> <figure><img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Nuchal.jpg" alt="Child with nuchal fold at back of neck" /> </figure> <p>Increased nuchal fold (area at the nape or back of the neck)</p></li><li> <figure><img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Neck.jpg" alt="Child with normal neck compared to child with broad or webbed neck" /><figcaption>Top: A normal neck. Bottom: Broad neck with excess skin.</figcaption></figure> <p>Broad neck with excess skin (webbed neck)</p></li></ul><h3>Skeleton and limbs</h3><ul class="akh-steps"><li> <figure> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Scoliosis.jpg" alt="Orange dotted line showing the curve in a child's spine" /> <figcaption>The orange dotted line represents the curve in the child's spine (scoliosis). The solid orange line shows where the child's spine should be straight. </figcaption></figure> <p>Abnormal side-to-side curvature of the spine (<a href="/article?contentid=2006&language=english">scoliosis</a>).</p></li><li> <figure> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_Chest.jpg" alt="Child on the left with sunken chest and child on the right with protruding chest" /> <figcaption>On the left is an example of a sunken chest. On the right is an example of a protruding chest.</figcaption></figure> <p>Sunken chest (pectus excavatum) or a protruding chest (pectus carinatum)</p></li><li>Short stature</li><li>Swollen hands and feet (lymphedema) usually seen in infants</li></ul><h3>Brain</h3><ul><li>A spectrum of learning difficulties</li><li>Impaired hearing </li><li>Delayed milestones</li></ul><h3>Genitals</h3><ul><li> <a href="/article?contentid=884&language=english">Undescended testicles</a></li><li>Delayed puberty onset</li></ul><h3>Feeding and nutrition</h3><ul><li>Feeding difficulties in infants and small children</li></ul><h3>Blood</h3><ul><li>Increased tendency to bleed<br></li><li>A rare but increased risk of some types of cancer</li></ul><h2>Causes of Noonan syndrome</h2><p>Noonan syndrome is caused by one of several <a href="/body/interactive?module=genetics">genes</a> that play a key role in the normal functioning of cells. At least 12 genes have currently been associated with Noonan syndrome.</p><p>In most cases (60%), Noonan syndrome is caused by a genetic change (variant) that occurs for the first time (de novo) in the child. </p> <figure class="asset-c-80"> <span class="asset-image-title">De novo inheritance</span> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_de_novo_mutation_EN.jpg" alt="Baby inherits one copy of gene from each unaffected parent with spontaneous new gene variant causing baby to be affected with Noonan syndrome." /></figure> <p>Noonan syndrome can also be inherited from a parent. Most cases of inherited Noonan syndrome are inherited in an autosomal dominant manner. This means that if a parent has Noonan syndrome, there is a 50% chance in each pregnancy to have a child with Noonan syndrome. </p> <figure class="asset-c-80"> <span class="asset-image-title">Autosomal dominant inheritance</span> <img src="https://assets.aboutkidshealth.ca/AKHAssets/Noonan_IMD_autosomal_dominant_EN.jpg" alt="Baby receives genes from affected parent and unaffected parent resulting in 50% chance of having Noonan syndrome." /></figure> <p>When the genetic change occurs de novo in the child, there is a less than 1% chance for the parents to have another child with Noonan syndrome.</p><p>There are a number of options for genetic testing either prior to or during a pregnancy for families that have an increased chance to have a child with Noonan syndrome. A <a href="/article?contentid=343&language=english">genetic counsellor</a> can help review these options. </p><h2>Diagnosis of Noonan syndrome</h2><p>The diagnosis of Noonan syndrome can be made either clinically or by genetic testing. A genetic change associated with Noonan is found in about 80-85% of individuals with Noonan syndrome. This means that a negative genetic test does not rule out the diagnosis. Genetic testing has important implications for genetic counselling and management.</p><h2>Treatment of Noonan syndrome</h2><p>There is currently no single treatment for Noonan syndrome, but it is often possible to successfully manage several aspects of the condition. Studies are underway for novel treatments.</p><p>Every child with Noonan syndrome is different and many go on to lead normal lives. Some children with Noonan syndrome can have delayed milestones or learning difficulties. However, when recognized early, they respond well to additional support. Children with Noonan syndrome typically also require regular follow-up by several medical specialties.</p><p>Patients with heart conditions may require a heart intervention or surgery, depending on the symptoms and severity of the condition. The treatment will depend on the specific heart defect. With pulmonary stenosis, the aim is to relieve the thickening of the valve and to make it easier for the blood to flow from the heart to the lungs. This can be achieved by a cardiac catheter (e.g. <a href="/article?contentid=1669&language=english">balloon dilation</a>) or, more frequently, by cardiac surgery (open-heart surgery). For information on treatment of hypertrophic cardiomyopathy, please see the article Hypertrophic cardiomyopathy. </p><h2>Heart conditions associated with Noonan syndrome</h2><p>About 80% of Noonan syndrome cases involve a heart condition. These conditions fall into two main categories: congenital heart disease (about 80% of cases involving a heart condition) and hypertrophic cardiomyopathy (about 20% of cases involving a heart condition).</p><h3>Congenital heart disease: Pulmonary stenosis</h3><p> <a href="/article?contentid=1619&language=english">Pulmonary valve stenosis</a> is the most common heart condition associated with Noonan syndrome, seen in up to 70% of cases. The pulmonary valve controls the blood flow from the heart to the pulmonary artery, which then leads to the lungs so the blood can get oxygen. Stenosis means that the valve is thick and its opening is narrower than normal, which makes it hard for the blood to flow through it. </p><p>In most cases this pulmonary valve narrowing is only mild and will not cause your child to have any symptoms or to require any intervention. Your child’s doctor might hear a murmur as they listen to your child’s chest. This is related to the turbulence of the blood as it crosses the thickened valve. </p><p>Less frequently, the pulmonary valve narrowing may be moderate or severe. These cases might require a cardiac intervention or a surgery.</p><h3>Congenital heart disease: Other heart defects</h3><p>Other heart defects may occur in Noonan syndrome patients, although this is less common. The majority of these defects are related to the abnormal formation of the walls that divide the left and the right sides of the heart. The atria are located in the upper part of the heart. The wall that separates the right and left atria is called the atrial septum. A defect (hole) in this wall is called an <a href="/article?contentid=1607&language=english">atrial septal defect (ASD)</a>. The majority of ASDs will produce no symptoms at first and might only be detected due to a murmur.</p> The ventricles (the pumping chambers) are located in the lower part of the heart. The wall that separates the right and left ventricles is called the ventricular septum. A defect in this wall is called a <a href="/article?contentid=1626&language=english">ventricular septal defect (VSD)</a>. Depending on the size of this hole, your child might have no symptoms at all or present with heart failure symptoms. This lesion will also produce a murmur that your child’s doctor may be able to hear with a stethoscope (auscultation). For more information on heart failure please see <a href="https://www.aboutkidshealth.ca/heartfailure">aboutkidshealth.ca/heartfailure</a>. <p></p><h3>Hypertrophic cardiomyopathy</h3><p>Hypertrophic cardiomyopathy is a condition in which the heart muscle becomes unusually thick. This can affect the amount of blood pumped to the body and cause heart rhythm problems. Many patients with this condition may not experience any symptoms at all, the only sign being a heart murmur on auscultation. Some patients may have shortness of breath, chest pain, dizziness, fainting, palpitations and, in rare cases, cardiac arrest. For more information please see the article <a href="/article?contentid=1629&language=english">Hypertrophic Cardiomyopathy</a>.</p><h2>Resources</h2><p><a href="https://www.teamnoonan.org/">Noonan Syndrome Foundation (USA)</a></p><p><a href="https://www.noonansyndrome.org.uk/">Noonan syndrome association (UK)</a></p><p><a href="https://noonansyndrome.com.au/support/">Noonan syndrome awareness association (Australia)</a></p><p><a href="http://ghr.nlm.nih.gov/condition/noonan-syndrome">Genetics Home Reference</a><br></p>Noonan syndrome and congenital heart conditionsFalse

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