Apert syndrome is a rare genetic disorder that is usually present at birth, causing an abnormal skull and fused fingers and toes. Other body parts and organs may also be affected. Surgery and other treatments can increase the chances of a child with Apert syndrome developing normally. You can find more information below.
What is Apert syndrome?
Apert syndrome; It is a rare genetic disease that is evident at birth. In people with Apert syndrome; there may be obvious defects or disabilities (malformations) in the skull, face, hands and feet. Apert syndrome is characterized by craniosynostosis (disease caused by too early fusion of the skull bones), a condition in which the fibrous joints (sutures) between the bones of the skull close prematurely. This can cause the top of the head to appear pointed and can affect the facial bones. Some fingers or toes may be fused or webbed. Affected children may also have intellectual disabilities.
The severity of the symptoms of Apert syndrome varies from person to person. Apert syndrome is almost always caused by new genetic changes (mutations) that occur randomly. Rarely, it is inherited in an autosomal dominant (transmission of mutated gene, through dominant inheritance) manner. People with Apert syndrome may have to seek treatment in this area if they show certain symptoms.
Who is affected?
Apert syndrome is estimated to occur in approximately 1 in 65,000 births. There appear to be relatively equal numbers in men and women. Since the disease was originally described in 1894 and 1906, more than 300 cases have been reported. It has been reported that Asian individuals have the highest incidence of Apert syndrome (the number of certain diseases in a given population in a given period of time).
Causes of Apert syndrome
Apert syndrome is caused by a change (mutation) in the fibroblast (the basic cell of the connective tissue that produces collagen and fibers in the body) growth factor receptor-2 ( FGFR2 ) gene. This gene plays a critical role in skeletal development. Genes provide instructions for creating proteins that play different roles in our bodies. When a gene is mutated, the protein product may not work as it should.
In Apert syndrome, mutations in FGFR2 cause these receptors to fail to communicate properly with fibroblast growth factors. This condition affects the formation of normal fibrous joints (sutures) in the brain and can inhibit the development of many other structures in the body. This malformation is what causes the body defects seen in Apert syndrome.
In almost all reported patients, the disorder was caused by one of two specific mutations of the FGFR2 gene. (These mutations are called “Ser252Trp” and “Pro253Arg.”) These mutations can cause slightly different syndromes, including the severity of syndactyly (conjoined finger). Different mutations in the FGFR2 gene can cause other related disorders such as Pfeiffer syndrome, Crouzon syndrome, and Jackson-Weiss syndrome .
In 95% of patients, Apert syndrome is caused by a new mutation in the FGFR2 gene. These new mutations appear to occur randomly for unknown reasons (occasional). It has been reported that sporadic cases (rare and irregularly occurring diseases) may be associated with increasing age of the father.
Although rare, Apert syndrome is inherited in an autosomal dominant manner. Dominant genetic disorders occur when only a single copy of the mutation is passed on to cause a particular disease. The risk of transmission from a parent with an affected gene to the baby is 50% for each pregnancy. The risk is the same for men and women.
Symptoms of Apert syndrome
Children with this genetic condition have a characteristic appearance because the skull plates are fused and the midface bones do not grow out of proportion. If the irregular skull shape (skull plate fusion) is severe, the pressure inside the brain (intracranial pressure) may increase, requiring immediate treatment.
Those with Apert syndrome are at risk of developing hydrocephalus. Hydrocephalus occurs when cerebrospinal fluid (CSF) stops circulating or is reabsorbed. CSF accumulates in the ventricles (cavities) of the brain, causing an increased pressure in the brain.
Rarely, the bones of the spine in the neck (cervical spine) may also be affected , causing a condition called Chiari malformation , in which the base of the brain is compressed.
The lack of growth of the midface bones can affect breathing because the airway is narrow. A small number of children also have heart problems that require regular lifelong monitoring.
Affected children may have a cleft palate. Vision may also be affected as the eyes are not protected by the eyelids. Most children with this genetic condition have mild to severe learning difficulties or developmental delays. Syndactyly, or fused fingers and toes, is another sign of Apert syndrome.
In summary, the symptoms are:
- Long skull and high prominent forehead
- Underdeveloped upper jaw
- Prominent eyes that appear bulging and can be widely separated
- Small nose
- Slower mental development due to abnormal growth of the skull
- Cleft palate
- fused fingers and toes
- Vision problems caused by an imbalance in the eye muscles
- recurrent ear infections that can cause hearing loss
- Difficulty breathing due to a small nose and airway passages
- Increased sweating (especially when asleep) due to hyperactive sweat glands
- acne problems, especially during adolescence
Apert syndrome diagnosis
The diagnosis of this genetic syndrome is most often made at birth or in infancy. The individual is diagnosed through clinical evaluation and various special tests. Physical features such as facial anomalies or syndactyly will also be identified at the time of diagnosis.
Skeletal abnormalities and congenital heart defects can be detected using a computed tomography scan or imaging such as magnetic resonance imaging. Hearing impairment can be detected during the newborn screening hearing test. Doctors can also test for mutations in the FGFR2 gene, which can provide a genetic diagnosis of Apert syndrome .
In some cases, features of this genetic disorder can be detected before birth. This will be done with prenatal 2D or 3D ultrasound or magnetic resonance imaging .
Ultrasound is a minor, non-damaging procedure that can see an image of the fetus. Thus, it can detect differences in skull shape, facial anomalies and syndactyly. Magnetic resonance imaging of the fetus can give more details of brain formation than ultrasound.
Apert syndrome treatment
Treatment of Apert syndrome varies depending on what symptoms a person has. Such treatment may require the care of a team of specialists, including pediatricians and surgeons.
Specialists include audiologists, neurosurgeons, doctors specializing in skeletal, joint and muscle disorders (orthopedists), doctors specializing in ear, nose, and throat conditions (otolaryngologists) and physicians who study heart abnormalities (cardiology).
Specific treatments for this genetic syndrome are symptomatic and supportive. Craniosynostosis and hydrocephalus can cause abnormally increased pressure in the skull and brain. In such cases, surgery may be recommended to correct the craniosynostosis within 2 to 4 months after birth. For people with hydrocephalus, surgery may also involve placing a tube (shunt) to drain cerebrospinal fluid (CSF) away from the brain. CSF is discharged to another part of the body where it can be absorbed.
Corrective and reconstructive surgery may be recommended to help correct craniofacial malformations. Surgery can also help correct polydactyly, syndactyly, and other skeletal defects or physical abnormalities.
For those with congenital heart defects, treatment with certain medications, surgery, or other measures may be necessary. For some people with hearing impairment, hearing aids can be helpful.
Early intervention can be important to ensure that children with Apert syndrome reach their full potential. Special services such as physical therapy , occupational therapy, and special education may also be helpful.
Genetic counseling is recommended for affected individuals and their families. A genetic counselor can explain the causes of Apert syndrome. They can also discuss the risk of having a new child with Apert syndrome. Psychosocial support is also essential for the whole family.
Long-term outlook in Apert syndrome
The outlook for babies with Apert syndrome depends on how severe the condition is and which body systems are affected. Apert syndrome can be more serious if it affects a child’s breathing or causes pressure inside the skull, but these problems can be corrected surgically.
Children with Apert syndrome often have learning disabilities. Some children are more severely affected than others.
Because the severity of Apert syndrome can vary greatly, life expectancy is difficult to predict. This condition may not have a large impact on a child’s life expectancy, especially if they do not have heart defects.
Apert syndrome can change the shape of the baby’s skull and face at birth. It can also lead to complications such as breathing problems and slower learning.
Today, surgeons can correct many of these problems so that children with Apert syndrome can live independently. However, it should be noted that some children will need additional help with school and daily life as they get older.