Hunter Syndrome: Moms and Dads, let's be aware of this rare condition

Do you sometimes feel that your little one is a little behind in development? Or does his facial features and body shape seem a little different from other children his age? Sometimes, behind these things, there may be a rare condition that we haven't even heard of. Today, we're talking about a disease that many people don't know about, but it's very important for us as parents to be aware of. That's Hunter Syndrome.

Simply put, what is Hunter Syndrome?

Hunter syndrome is a very rare, genetic condition. This is when your child's body can't properly break down and digest certain complex sugar molecules. Think of it like little workhorses inside our bodies, which we call enzymes. Their job is to break down and clean up the things that come into our bodies, the things that we don't need.

A child with Hunter syndrome is born with a very small amount of the enzyme that is needed to break down a special type of sugar molecule. So what happens then? Those sugar molecules that cannot be broken down gradually begin to accumulate in the child's organs and tissues. Just like garbage that is not removed, it accumulates. Over time, this accumulation can harm the child's physical and mental development.

Doctors divide this disease into two main parts:

1. Severe type of symptoms: This is the most common type (about 60%). The symptoms of these children progress quickly, and their intellectual abilities are also affected. Usually, by the age of 6-8, the child begins to have problems with basic activities.

2. Mild type: Symptoms appear slowly. The child's intelligence is usually not significantly affected.

This disease belongs to a group of diseases called mucopolysaccharidoses. That is why Hunter syndrome is also called mucopolysaccharidosis type II (MPS II) .

How common is this disease? Who is most likely to get it?

This is a very rare disease . Also, it mostly affects boys . According to statistics, about one in every 100,000 to 170,000 boys born is diagnosed with this disease.

However, girls can be carriers of the defective gene that causes the disease. Simply put, a girl has two X chromosomes, while a boy has only one. So even if a girl inherits the defective X chromosome, her other healthy X chromosome can make the enzyme she needs. But if a boy inherits the defective X chromosome, he has no other choice and develops symptoms.

What are the symptoms of this disease?

Symptoms usually begin to appear in a child between the ages of 2 and 4. These symptoms can vary from child to child. Some children have fewer symptoms, while others have more.

Why does this disease actually occur?

This is caused by a mutation in the IDS gene . The IDS gene is responsible for controlling the production of an enzyme called iduronate 2-sulfatase (I2S), which our body needs.

This I2S enzyme breaks down complex sugar molecules called glycosaminoglycans (GAGs). Children with Hunter syndrome (MPS II) either do not produce this I2S enzyme at all, or produce it in very small amounts.

This causes sugar molecules called GAGs to accumulate in the lysosomes, which are the recycling centers of cells. Lysosomes are like the recycling centers of cells. Diseases that occur due to the accumulation of things inside lysosomes are also called lysosomal storage disorders . Over time, these accumulations damage the body's organs.

What other complications can occur due to this disease?

Depending on the severity of the disease, the child may develop various complications. Doctors use medications and sometimes even surgery to manage these complications.

How to diagnose the disease?

Your child's doctor will perform several tests to diagnose this disease.

• Urine test: This checks for abnormally high levels of the sugar molecules (GAGs) we talked about earlier in the urine.
• Blood tests: This can determine whether the activity of the relevant enzyme in the blood is low or absent.
• Genetic testing: This test is done to confirm whether the genetic mutation that causes the disease is present.

How is it treated?

There is no cure for Hunter syndrome yet . However, there are treatments to control the course of the disease, detect complications as early as possible, and improve the child's quality of life.

The best treatment for this is Enzyme Replacement Therapy (ERT) . This involves artificially producing the enzyme that is missing in the body and giving it to the child. This medicine is called idursulfase (Elaprase®) . This treatment is usually given intravenously once a week.

In addition, research on gene therapy is also taking place around the world, and there is hope that it will lead to better treatments in the future.

What can you say about the child's future?

I know this is a very difficult question to ask. In severe cases of the disease, a child's life expectancy can be short. Usually between 10 and 20 years. However, children with mild symptoms can live into adulthood.

Questions to ask your doctor

If you are diagnosed with this disease in your child, it is normal to have many questions in your mind. Ask your doctor about these things clearly.

• Is this a severe or mild form of the disease?
• What will be my child's short-term and long-term situation?
• How will this disease affect my child's life?
• What are the treatment options?

It's normal for a family to be shocked and saddened when they learn about a medical condition like this. Remember that you are not alone at this time. Talk to your doctor, family, and close friends about this. We all need to work together to give your child the best possible care.