Hunter syndrome can be detected before the baby is born. The activity of the I2S enzyme in placental tissue or amniotic fluid is measured in this manner. It is an important consideration in evaluating patients with fetal hydrops. Patients with normal enzyme levels do not require further evaluation unless complications arise during pregnancy.
Hunter syndrome is typically suspected in young persons who exhibit signs and symptoms of the disorder. The primary early warning sign that a kid may have Hunter syndrome is characteristic alterations in facial characteristics. In most cases, the diagnosis is made between the ages of 2 and 4 years. Kids with Hunter syndrome often have large heads, wide hips, short stature, and thin limbs. They also usually have hearing loss and vision problems.
The only way to confirm the diagnosis is through genetic testing. Blood samples are drawn from the patient's arm or leg and the DNA is extracted from it. This process allows for the identification of mutations in the ALB gene, which is associated with Hunter syndrome.
ALB is an albumin protein. Albumin is one of several nutrients that help transport other substances in your blood. Decreased levels of albumin can lead to increased amounts of toxic substances in the blood. Hunter syndrome is caused by mutations in the ALB gene that affect its ability to make functional protein. Some mutations cause premature termination of the protein, while others change one of its amino acids.
People with Hunter syndrome experience many health problems due to the lack of albumin in their bodies. These include kidney failure, respiratory problems, and dementia. There is no cure for Hunter syndrome; however, treatments are available to manage some of the symptoms. For example, patients may require artificial joints, heart valves, or other organs as they grow up.
Hunter syndrome is a very uncommon, hereditary genetic condition caused by an enzyme that is either absent or dysfunctional. Hunter syndrome is caused by a deficiency of the enzyme iduronate 2-sulfatase in the body. This disease affects only males; females are usually not affected.
The symptoms of Hunter syndrome will vary depending on how much activity a person with this disease does. People who do not do anything at all with their time sitting at home watching television or sleeping most of the day will likely not experience many problems as a result of their illness. On the other hand, people who participate in extreme sports such as rock climbing or skydiving may suffer from injuries that stem from their lack of mobility awareness.
People with Hunter syndrome may also have difficulties communicating due to problems with their voice box, called laryngeal muscles. Many times, these problems can be corrected through surgery.
Because of the variability in symptoms, people with Hunter syndrome need to be seen by a physician who specializes in pediatric diseases of the kidney and liver. The doctor will conduct a full medical history including questions about your child's behavior, abilities, and health concerns. A physical exam will be done, including testing for signs of mental retardation. Blood tests may be done to screen for hepatitis B virus (HBV) or hepatitis C virus (HCV).
Hunter syndrome is caused by a mutation in the IDS gene, which codes for the synthesis of a particular enzyme known as I2S. This specialized protein is generally located in cells' lysosomes, where it aids in the breakdown of complex sugars known as glycosaminoglycans (GAGs). Lack of this enzyme leads to an accumulation of GAGs in the blood and tissues of people with Hunter syndrome.
Hunter syndrome is inherited in an autosomal-recessive pattern. That means that only one copy of the mutated IDS gene is sufficient to cause the disease. People with Hunter syndrome have no immune system resistance to its own products. Thus, they are prone to chronic infection of the lungs, bladder, and other organs due to their high levels of mucopolysaccharides.
The severity of symptoms will vary depending on how many copies of the mutant IDS gene there are. Individuals who have one normal copy and one defective copy may show some mild symptoms including cognitive impairment, joint pain, and enlarged liver and spleen. Others may not show any symptoms at all. The onset of symptoms usually occurs between ages 1 and 5 years. Children with two defective copies of the IDS gene will develop full-blown Hunter syndrome with no signs of improvement even with treatment.
People with Hunter syndrome need regular replacement therapies to survive.