Hurler Syndrome: Treatment, Procedure, Cost and Side Effects

Hurler Syndrome is also known as mucopolysaccharidosis type I (MPS-I), Hurler's Disease or gargolysm.

Hurler syndrome is one of many inherited disorders. It is the condition in which the body is missing or does not have enough of an enzyme needed to break down long chains of sugar molecules. As a result, the molecules build up in different parts of the body and cause various health problems. Hurler Syndrome is inherited. Early treatment is difficult as the first clinical manifestations are not specific. Diagnosis is based on detection of increased urinary excretion of heparan and dermatan sulphate and confirmed by demonstration of enzymatic deficiency in leukocytes or fibroblasts. Genetic testing is available. Enzyme replacement therapies are currently in use. It has proven useful in reducing non-neurological symptoms and pain. Bone marrow transplantation (BMT) and umbilical cord blood transplantation UCBT) can be used as treatments.

A blood or marrow transplant begins with chemotherapy, with or without radiation, to destroy the diseased cells and marrow.

Transplantation:

The type of transplant used for Hurler syndrome is an allogeneic transplant. This type of transplant uses healthy blood-forming cells from a family member, unrelated donor, or umbilical cord blood unit. For an allogeneic transplant, a patient gets chemotherapy, with or without radiation, prior to transplant to prepare his or her body for the treatment. Then the replacement cells are infused into the patient’s blood stream. From there, the cells find their way into the bone marrow, where they start making healthy red blood cells, white blood cells and platelets. These new cells have the enzyme needed to break down GAG and stop further damage to the body. The entire process, from start of chemotherapy or radiation until hospital discharge, can last weeks to months followed by many months of recovery at home.

Enzyme replacement therapy:

The enzyme is administered weekly, by slow injection (infusion), into a vein. The procedure for laronidase infusion takes several hours and must be performed weekly. Significant improvement in lung function and walking ability in children with Hurler syndrome after long-term treatment with laronidase has been reported. However, laronidase administered by intravenous infusion cannot enter the brain, since the brain is normally protected by mechanisms that prevent entry of drugs and other foreign substances from the bloodstream. Therefore, improvement in brain and central nervous system functioning is neither observed nor expected. Direct injection of laronidase into the brain has also been attempted, with promising results, but this treatment remains experimental.

Usually, when child is born, there won't be any symptoms regarding MPS-1. The child's facial feature changes only after 5-6 months. The child can immediately be treated, once the syndrome is found. Because children with untreated Hurler syndrome have physical and mental problems that get worse over time, it is best to have a transplant as soon as possible. Children who get a transplant early enough can have normal or near-normal mental development, and damage to the organs is stopped.

Patients below age of 5 years are not allowed for ERT transplant.

There are no side effects/

Dietary modifications or lifestyle adjustments must be strictly practiced. Physical therapy and daily exercise may delay joint problems and improve the ability to move. If a blood or tissue sample from a blood relative with Hurler syndrome is available, DNA testing may be utilized to determine if a person is a carrier. Prenatal DNA testing may be performed if there is a family history of Hurler syndrome. However, there are serious risks associated with prenatal testing, including miscarriage. People with family histories of Hurler syndrome can meet with genetic counsellors. These professionals can help patients understand the risks of having a child with Hurler syndrome. A genetic counsellor can also explain the different types of genetic tests, including their potential risks and benefits.

Hurler Syndrome can't be cured completely, as it is a genetic disorder. However, there are many techniques coming up, Gene Therapy helps eradicate the disease for some extent.

Hurler Syndrome has a costly cure. It costs 10-20 lakhs approximately.

Through BMT and Gene therapy, patient can eradicate the syndrome. Depending on the part of the body affected, there is the chance for the complete cure. However, few behavioural changes remain forever.