Achondroplasia is a problem with bone growth characterized by a disproportionate and stunted body.
This condition is a common bone growth disorder. People with this condition will have a relatively normal-sized sternum.
However, the legs and arms tend to be shorter, resulting in dwarfism. The average adult male with achondroplasia is about 131 centimeters tall.
Meanwhile, the average adult female height is 124 centimeters. Despite their physical differences, people with achondroplasia have a similar intelligence level to people of normal height.
Causes of Achondroplasia
This disease occurs due to a genetic mutation in FGFR3, a gene responsible for producing a protein called Fibroblast Growth Factor Receptor 3.
This type of protein has a very important role in the ossification process or the process of changing cartilage into hard bone.
Mutations that occur in this gene will result in the protein being unable to carry out its tasks and functions properly.
Finally, there is a disturbance in the change of cartilage into hard bone.
Bones will also grow shorter and have an abnormal shape, especially in the legs and arms.
Causes of Achondroplasia
In general, mutations that occur in the FGFR3 gene in achondroplasia sufferers occur in two ways:
1. Mutations that occur spontaneously
About 80 percent of achondroplasia cases occur due to genetic mutations that are not inherited or passed down from parents.
The mutation occurred spontaneously and it is still not known for certain what caused it.
2. Inherited mutations
Meanwhile, about 20 percent of achondroplasia cases occur because they are inherited from one or both parents.
If one parent has achondroplasia, the child has a 50 percent risk of developing the same condition.
However, if both parents experience the same thing, the risk of the child having it is as follows:
·
There is about a 25 percent chance that a child will have a normal
height.
·
There is a 50 percent chance that a child will have one type of
defective gene, resulting in achondroplasia.
·
There is about a 25 percent chance that a child will have two
defective genes, resulting in a life-threatening form of achondroplasia, also
known as homozygous achondroplasia.
Risk Factors for Achondroplasia
Many people often question whether achondroplasia is a hereditary (genetic) disease or not.
The main risk factor for achondroplasia is a genetic defect passed down from parents to their children.
However, most cases of achondroplasia are not inherited, so anyone can experience this condition.
QuotingCleveland Clinic, About 80 percent of individuals with achondroplasia have parents of normal height and are born with a new gene change (de novo mutation).
It is rare for these parents to have a child with achondroplasia.
Meanwhile, there is only a 50 percent chance that a person with achondroplasia and a partner who does not have achondroplasia will have a child with the disorder.
If both parents have achondroplasia, there is a 25 percent chance that the child will be born with homozygous achondroplasia.
This results in stillbirth or death soon after birth.
Symptoms of Achondroplasia
What are the symptoms of achondroplasia? At birth, babies with achondroplasia may exhibit the following symptoms:
·
The legs, fingers, and arms appear short.
·
The head size looks larger with a prominent forehead.
·
After teething, you will see that the teeth are crowded and not
aligned.
·
Having problems with the shape of the spine, for example lordosis
or kyphosis.
·
The spinal canal is narrow.
·
The soles of the feet are wide and short.
·
Legs that are shaped like the letter O.
·
Weak muscle strength.
In addition, long-term symptoms that may be seen include:
·
Back and leg pain.
·
Breathing problems (apnea).
·
Obesity.
·
Recurrent ear infections.
·
Curved spine.
·
Crooked legs.
·
Excess fluid in the brain (hydrocephalus).
·
Obstructive sleep apnea.
Diagnosis Achondroplasia
This condition can be detected while still in the womb and after birth.
1. During pregnancy
A diagnosis can be made in parents with this condition. Types of tests include:
·
Ultrasonography (USG).This
examination is carried out to determine the health and development of the fetus
in the womb and to determine whether or not there are early symptoms of
achondroplasia, such as a larger head size.
·
Detection of FGFR3 gene mutations.Examination
of gene mutations while still in the womb can be done by taking samples of the
mother's amniotic fluid or placental tissue, which is calledchorionic villus
samplingHowever, this procedure can increase the risk of miscarriage, so
it's best to discuss it with your doctor.
2. After birth
Initially, the doctor will perform a physical examination and interview both parents regarding their family health history in detail.
Achondroplasia condition can be easily recognized by the legs which are disproportionate and appear shorter than normal size.
To ensure the accuracy of the diagnosis, the doctor can also carry out a series of further examinations, one of which is a DNA test.
This test involves taking a DNA sample from the blood, for laboratory testing.
Then, the doctor will use this DNA sample to detect the presence or absence of FGFR3 gene abnormalities.
Can a person with achondroplasia give birth naturally?
Essentially, the success of a vaginal delivery is greatly influenced by the size of the mother's pelvis. The shorter a woman, including those with achondroplasia, the smaller her pelvis typically is. A narrow pelvis can restrict the baby's head's ability to pass through the birth canal.
During normal labor, the pelvis naturally widens to make room for the baby. However, in women with achondroplasia, this dilation capacity is often suboptimal due to the smaller bone shape and size of the pelvic cavity.
This condition makes it very likely that the baby's head will not be able to pass through the pelvis, making the normal delivery process riskier.
However, this doesn't mean a natural birth is completely impossible. Some women with achondroplasia can still have a natural birth if the fetus is smaller, the baby is positioned optimally, and the mother's pelvis is deemed to have sufficient space.
All of this can only be determined through a thorough screening process, such as a pelvic exam, ultrasound, and close monitoring of fetal growth by an obstetrician.
Despite the potential for complications, most doctors still recommend a cesarean section. This is to minimize the risk of complications for both mother and baby, such as birth canal obstruction or pelvic bone injury.
Achondroplasia Treatment
Treatment options that can be considered for this condition are:
1. Medical check-up
Regular medical check-ups are very important to monitor the growth of the sufferer's body.
This examination includes measuring the ratio of the upper and lower body, as well as body weight.
Maintaining body weight is useful for preventing complications due to obesity.
2. Hormone therapy
Children with achondroplasia may be advised by their doctor to undergo regular hormone therapy to help increase bone growth.
The goal is for children to have better posture when they grow up.
3. Medicines
Doctors usually prescribe medications such as antibiotics to people with achondroplasia who experience ear infections, a common health problem.
Then, the use of anti-inflammatory drugs can be an option if the sufferer experiences arthritis.
4. Operation
Another treatment is surgery, which doctors perform to relieve the symptoms experienced by sufferers or to overcome complications that arise.
The surgical options are:
·
A cesarean section is recommended for pregnant women with
achondroplasia, who have a small pelvis. A similar procedure is also
recommended for fetuses with achondroplasia and a larger head to reduce the
risk of bleeding.
·
Orthopedics can be an option if the sufferer has O-shaped legs.
·
Ventriculoperitoneal shunt, which
doctors do if the sufferer has hydrocephalus.
·
Lumbar laminectomy, which doctors perform to treat spinal
stenosis.
5. Managing symptoms
Symptom management will focus on managing potential complications, for example:
·
Manage your weight and adopt healthy eating habits to prevent
obesity.
·
Ventriculoperitoneal shunt surgery to reduce fluid pressure on the
brain. In addition, craniocervical junction compression can correct
life-threatening complications.
·
Removal of adenoids and tonsils through surgery.
·
Managing growth hormones.
·
Use of nasal maskscontinuous positive airway pressure (CPAP)
for apnea.
·
Using ear tubes or antibiotics to prevent ear infections.
·
Get social support from family, close friends, and the
environment.
Can Achondroplasia Be Cured?
To date, there is no treatment that can completely cure achondroplasia because this condition stems from a genetic mutation in bone growth. This means the disorder is present early in development and is irreversible.
Treatment provided by doctors focuses more on reducing symptoms and preventing long-term complications. For example:
·
Physiotherapy to help improve posture and mobility.
·
Nerve and spinal monitoring to prevent narrowing of
the spinal canal.
·
Certain orthopedic surgical procedures, if
necessary, to correct bone deformities or reduce pain.
·
Child growth monitoring early so that complications can
be treated more quickly.
This approach is not a “cure,” but it is essential to maintaining optimal quality of life for people with achondroplasia.
Complications of Achondroplasia
Lack of treatment or late treatment can result in a number of complications, including:
·
Overweight or obesity.
·
Recurrent ear infections occur due to narrowing of the ear canal.
·
Limited movement due to leg and arm abnormalities.
·
Having spinal stenosis, a narrowing of the spinal canal that
causes the nerves in the spinal cord to experience pressure.
·
Hydrocephalus, a buildup of fluid in the ventricles of the brain.
·
Sleep apnea, stopping breathing while sleeping.
Prevention of Achondroplasia
There is nothing you can do to prevent achondroplasia.
So, if you have a family history of this condition, get tested early, especially if you're in the early stages of pregnancy.
Because, early examination can detect the potential for this disease in the fetus in the womb.