What is Achondroplasia?
Achondroplasia is a problem with bone growth characterized by a disproportionate and stunted body.
This condition is one of the most common bone growth problems. People with this health disorder will have a fairly normal chest bone size.
However, the size of the legs and arms tends to be shorter, causing sufferers to have a dwarf body or dwarfism. The average height of achondroplasia sufferers for adult males is around 131 centimeters.
Meanwhile, for adult women, the average height is 124 centimeters. Although physically different, people with achondroplasia have the same level of intelligence as people with normal height.
Symptoms of Achondroplasia
What are the symptoms of achondroplasia? When a baby is born, a baby with achondroplasia can already show symptoms, namely:
- The legs, fingers, and arms appear short.
- The head size appears larger with a prominent forehead.
- After teeth grow, the teeth will appear to be crowded and misaligned.
- Having problems with the shape of the spine, such as 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.
- Bowed legs.
- Excess fluid in the brain (hydrocephalus).
- Obstructive sleep apnea.
Diagnosis of Achondroplasia
This condition can be detected while still in the womb and after birth.
1. During pregnancy
Diagnosis can be done on parents with this condition. Types of examinations include:
- Ultrasonography (USG). This examination is carried out to determine the health and development of the fetus in the womb as well as 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 called chorionic villus sampling. However, this procedure can increase the risk of miscarriage, so it is best to discuss it with your doctor.
2. After birth
Initially, the doctor will perform a physical examination and interview both parents regarding the family’s medical 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 People with Achondroplasia Give Birth to Babies Normally?
The shorter a woman’s body, the smaller her pelvis will be.
Meanwhile, pelvic size is an important factor that influences the success of childbirth.
When a woman gives birth naturally, the pelvis widens to create space for the baby to pass through the pelvis.
However, in achondroplasia sufferers who have a narrow pelvis, it is likely that the fetal head will not be able to pass through the pelvic cavity.
However, women with this condition still have the possibility of giving birth normally.
As long as the delivery has first gone through a strict screening process under the supervision of a doctor.
However, it is better to give birth by cesarean section, for safety reasons.
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 from parents to their children.
However, most cases of achondroplasia are not inherited, so anyone can experience this condition.
According to the Cleveland 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, then there is a 25 percent chance that the child will be born with homozygous achondroplasia.
This results in stillbirth or death soon after birth.
Causes of Achondroplasia
This disease occurs due to a genetic mutation of FGFR3, the part of the 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 the 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 the 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 will have a 50 percent risk of developing the same condition.
However, if both parents experience the same thing, here are the risks of the child having it:
- There is about a 25 percent chance that the child will have a normal height.
- There is almost 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 dangerous form of achondroplasia, called homozygous achondroplasia.
Achondroplasia Treatment
Treatment options for this condition include:
1. Medical check-up
Regular medical check-ups are very important to know 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 recommended by their doctor to undergo regular hormone therapy to help increase bone growth.
The goal is for children to have a better body 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 that sufferers feel or to overcome complications that arise.
The surgical options are:
- Cesarean section for pregnant women with achondroplasia with small pelvic bones. A similar procedure is an option if the fetus has achondroplasia with a larger head size 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. Also with craniocervical junction compression, to correct life-threatening complications.
- Removal of adenoids and tonsils through surgery.
- Managing growth hormones.
- Use of a continuous positive airway pressure (CPAP) nasal mask 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?
Until now, there is still no treatment that can completely overcome this condition.
Treatment is only carried out by doctors with the aim of helping to relieve symptoms or prevent more serious complications.
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 the narrowing of the ear canal.
- Limited movement due to leg and arm abnormalities.
- Suffering from 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 the condition, get checked early. Especially for mothers who are still in early pregnancy.
Because early examination can detect the potential for this disease in the fetus in the womb.