Madisons Foundation - Moms And Dads In Search Of Needed Support

What

Sanfilippo syndrome is a rare, inherited condition classified as a lysosomal storage disorder. It is caused by a missing or poorly functioning enzyme. In affected individuals, the missing or poorly functioning enzyme prevents the normal breakdown of waste material inside the body’s cells. This results in the buildup and storage of waste material in almost every cell of the body. As a result, cells do not function properly. This results in the progressive damage to the heart, bones, joints, respiratory system, and central nervous system. The disease is not usually apparent at birth. Behavioral problems and mental deterioration develop with age, as more cells become damaged by the accumulation of waste material.

Who

Sanfilippo syndrome occurs in approximately 1 out of every 25,000 newborns. Girls and boys of all races and ethnicities are affected equally.

Signs and Symptoms

Typically, symptoms begin to develop after the age of 2 years and gradually worsen. Facial features may be normal or slightly coarse with full lips and heavy eyebrows that meet above the nose. Most noticeable is the presence of excessive and coarse hair. Stiff joints, an enlarged liver and spleen and occasionally an enlarged head may develop. Early on in the course of the disease children can begin to develop difficult behavior. Later, hyperactivity, restlessness and trouble with sleeping can become more common. Speech, language and intelligence gradually deteriorate after age 6 years. Usually by 10 years of age difficulty walking and running and frequent falling occurs. Other signs and symptoms include; • Diarrhea • Recurrent upper respiratory tract infections • Deafness • Blindness • Short stature • Seizures

Possible Causes

Sanfilippo syndrome is inherited in an autosomal recessive manner. This means that two genes with a genetic change (mutation) are necessary to cause this disorder. The parents of the affected child are usually healthy, but each carries one copy of this gene with a change; they are a carrier for this disorder. When both parents are carriers, there is a 25% chance that each of their children will have this disorder. There are four different enzyme deficiencies that can cause Sanfilippo syndrome: type A, B, C, and D. Type A, the most common and most severe, is caused by a change in a gene which normally makes the enzyme heparin sulfatase. Type B is due to a deficiency of the enzyme N-acetyl-alpha-D-glucosaminidase (NAG). Type C is caused by a deficiency in acetyl-CoA, a-glucosamine N-acetyl transferase. Type D is caused by a deficiency in N-acetyl glucosamine 6-sulphate sulphatase. These enzymes are found in a special cell compartment called the lysosome. Lysosomes break down certain molecules including mucopolysaccharides, which are special sugar molecules. These enzyme deficiencies lead to the abnormal accumulation of heparin sulfate. The progressive build-up of this compound in the cells of the brain, bone, liver, kidney and spleen interferes with normal cell function.

Diagnosis

The diagnosis is first suspected by finding the above signs and symptoms on physical examination and a test of the urine can detect the build-up of the storage material (heparin sulfate). The diagnosis is confirmed by a special blood test that measures the activity of the deficient enzyme. A skin biopsy can also help confirm the diagnosis.

Treatment

No specific cure is available for Sanfilippo syndrome. The goal of treatment is to provide adequate nutrition and seizure control. Antiepileptic drugs can be used for the seizures which are usually easy to control. Evaluation by a neurologist, a doctor who specializes in diseases of the brain and the nervous system, is necessary to monitor for and treat seizures. Children with Sanfilippo syndrome have unusual sensitivity to anesthesia and they should be monitored very closely for complications related to anesthetics. Research is being done to find a treatment by enzyme or gene replacement.

Prognosis

Sanfilippo syndrome is a progressive disease and affected children usually do not survive beyond their 20s. Type A is the most severe and most affected children succumb during their teenage years. Children with very mild cases of type B may remain relatively healthy into adult life.

Connect with other parents

In the spirit of community and support, Madisons Foundation offers the unique service of connecting parents of children with rare diseases. If you would like to be connected to other parents of children with this disease, please fill out this brief form.

Weblinks

National MPS society, Inc
Non-profit organization providing support groups, education, information about research studies, counseling, and family networking.

Society for Mucopolysaccharide (MPS) Diseases
The MPS Society is a voluntary support group which represents children and adults with these disorders, their families and caregivers.

CLIMB (Children Living with Inherited Metabolic Diseases)
National organization providing information, news, financial support and networking.

Canadian Society for Mucopolysaccharide (MPS) and Related Diseases, Inc
National organization providing information, support, and newsletter.

Genetic Alliance
International coalition providing resources, education and networking.

March of Dimes Birth Defects Foundation
Non-profit organization providing support groups, education, information about research studies, counseling, and family networking.

Google Search for Sanfilippo Syndrome

References and Sources

www.emedicine.com/ped/topic2040.htm www.mpssociety.org/mps3.html www.specialchild.com/archives/dz-034.html www.nlm.nih.gov/medlineplus/ency/article/001210.htm