Skip to main content

Hunter Syndrome

 Hunter Syndrome



Overview

What is Hunter syndrome?

Hunter syndrome is a rare genetic disorder in which your child’s body doesn’t properly break down (digest) certain sugar molecules. When these molecules build up in organs and tissues over time, they can cause damage that affects physical and mental development.

Healthcare providers classify Hunter syndrome into severe and mild types. The severe type progresses faster and involves impaired intellectual abilities. In the most severe cases, children begin to experience problems with basic functioning between the ages of 6 and 8. The severe type occurs in about 60% of all cases.

Hunter syndrome is one of a group of diseases called mucopolysaccharidoses. Another name for Hunter syndrome is mucopolysaccharidosis type II, or MPS II.

Symptoms

The signs and symptoms of Hunter syndrome typically begin to appear in children between the ages of 2 and 4. Hunter syndrome symptoms vary in severity and may include:

Stiff joints.

Thickening of facial features including nostrils, lips and tongue.

Delayed appearance of teeth or wide spaces between teeth.

Larger than normal head, wide chest and short neck.

Hearing loss that gets worse with time.

Delayed growth, especially starting around age 5.

Enlarged spleen and liver.

White growths on the skin.

Causes

A genetic mutation in the IDS gene causes Hunter syndrome. The IDS gene is responsible for regulating the production of an enzyme in your body called iduronate 2-sulfatase (I2S). The I2S enzyme breaks down complex sugar molecules called glycosaminoglycans (GAGs). (MPS II gets its name because GAGs were formerly called mucopolysaccharides.)

In people with MPS II, their bodies don’t produce any or enough of the I2S enzyme. The missing enzyme causes a buildup of GAGs within the lysosomes of cells. Lysosomes are parts of cells that break down and recycle molecules. MPS II is a type of lysosomal storage disorder, which is a condition that causes sugar molecules to accumulate inside lysosomes. These buildups can damage organs and tissues throughout the body.

What are the risk factors for Hunter syndrome?

People are at a higher risk for Hunter syndrome if they have a biological family member with the disease.

Boys have a higher risk of inheriting the disease. This difference exists because the disease is linked to the X chromosome. Girls inherit two X chromosomes, while boys have only one. If a girl inherits the faulty gene, their other X chromosome can provide the necessary enzyme.

What complications are associated with Hunter syndrome?

Depending on its severity, Hunter syndrome can involve many complications. Providers use medications and sometimes surgery to manage these complications. They may include:

Breathing problems due to thickened tissue and blocked airways.

Heart disease.

Joint and bone abnormalities.

Declining brain function.

Carpal tunnel syndrome.

Hernias.

Seizures.

Behavioral problems.

Diagnosis and Tests

How is Hunter syndrome diagnosed?

Your child’s healthcare provider will use several tests to diagnose Hunter syndrome:

Urine test: A urine test checks for unusually high levels of sugar molecules.

Blood tests: Blood tests can show low or absent levels of enzyme activity, which is also a sign of the disease.

Genetic testing: Genetic testing identifies changes (mutations) in the gene to confirm the diagnosis.

Management and Treatment

How is Hunter syndrome treated?

Treatment for Hunter syndrome depends on the symptoms. A team approach, with specialists in different areas of expertise, could help manage your child’s condition. The goal of treatment is to slow the progression of the disease, identify possible complications related to the disease early and improve quality of life.

The treatment shown to do this best is enzyme replacement therapy. Healthcare providers replace the missing enzyme with a human-made version called idursulfase (Elaprase®). Providers usually deliver this treatment intravenously (through a needle inserted into your child’s vein) once a week. Genetic therapy (gene editing) trials are underway and may offer hope for Hunter syndrome patients. Results are awaited.

Type of Doctor Department : A pediatrician or primary care physician

Comments

Post a Comment

Popular posts from this blog

Charge Syndrome

Overview CHARGE syndrome is a recognizable genetic syndrome with known pattern of features. It is an extremely complex syndrome, involving extensive medical and physical difficulties that differ from child to child. CHARGE syndrome is correlated with genetic mutation to CHD7 and the prevalence of CHARGE syndrome is 1:10,000-1:15,000 live births. Babies with CHARGE syndrome are often born with life-threatening birth defects. They spend many months in the hospital and undergo many surgeries and other treatments. Swallowing and breathing problems make life difficult even when they come home. Most have hearing two little girls sitting on a carpet, one girl has a trach and is biting her finger.loss, vision loss, and balance problems that delay their development and communication. Despite these seemingly insurmountable obstacles, children with CHARGE syndrome often far surpass their medical, physical, educational, and social expectations. One of the hidden features of CHARGE syndrome is the ...
7 comments
Read more

Acral Peeling Skin Syndrome

Overview Acral peeling skin syndrome is a skin disorder characterized by painless peeling of the top layer of skin. The term "acral" refers to the fact that the skin peeling in this condition is most apparent on the hands and feet. Occasionally, peeling also occurs on the arms and legs. The peeling is usually evident from birth, although the condition can also begin in childhood or later in life. Skin peeling is made worse by exposure to heat, humidity and other forms of moisture, and friction. The underlying skin may be temporarily red and itchy, but it typically heals without scarring. Acral peeling skin syndrome is not associated with any other health problems. Symptoms The main symptom of APSS is the painless peeling of the skin. Most people can remove this skin by hand, and it may come off in sheets, similar to peeling skin after a sunburn. 1. blistering 2. itching 3. easily removable hairs If a person exposes their skin to heat, sweat, or water, they may notice that the...
Post a Comment
Read more

Sjogren's syndrome

Sjogren's syndrome Overview Sjogren's (SHOW-grins) syndrome is a disorder of your immune system identified by its two most common symptoms — dry eyes and a dry mouth. The condition often accompanies other immune system disorders, such as rheumatoid arthritis and lupus. In Sjogren's syndrome, the mucous membranes and moisture-secreting glands of your eyes and mouth are usually affected first — resulting in decreased tears and saliva. Although you can develop Sjogren's syndrome at any age, most people are older than 40 at the time of diagnosis. The condition is much more common in women. Treatment focuses on relieving symptoms. Symptoms The two main symptoms of Sjogren's syndrome are: Dry eyes . Your eyes might burn, itch or feel gritty — as if there's sand in them. Dry mouth. Your mouth might feel like it's full of cotton, making it difficult to swallow or speak. Some people with Sjogren's syndrome also have one or more of the following: Joint pain, swel...
Post a Comment
Read more