Navigate Up

Men's Center - A-Z Index

#
Q
Y
Z

Print This Page

Sanfilippo syndrome

Sanfilippo syndrome is metabolism disorder passed down through families. It makes the body unable to properly break down long chains of sugar molecules called glycosaminoglycans (formerly called mucopolysaccharides).

The syndrome belongs to a group of diseases called mucopolysaccharidoses (MPS). Specifically, it is known as MPS III.

See also:

Alternative Names

MPS III

Causes

Sanfilippo syndrome occurs when the substances (enzymes) needed to break down the heparan sulfate sugar chain are missing or are defective.

There are four main types of Sanfilippo syndrome, also called MPS III. Which type a person has depends on which enzyme is affected.

  • Sanfilippo type A is the most severe form. Persons with this type are missing or have an altered form of an enzyme called heparan N-sulfatase.
  • Sanfilippo type B occurs when a person is missing or doesn't not produce enough alpha-N-acetylglucosaminidase.
  • Sanfilippo C occurs when a person is missing or doesn't not produce enough acetyl-CoAlpha-glucosaminide acetyltransferase.
  • Sanfilippo D occurs when a person is missing or doesn't not produce enough N-acetylglucosamine 6-sulfatase.

The syndrome is inherited as an autosomal recessive trait. If both parents carry the defective gene related to this condition, each of their children has a 25% chance of developing the disease.

Sanfilippo syndrome is possibly the most common forms of MPS. It is seen in about 1 in 70,000 births. A family history of Sanfilippo syndrome increases the risk for this condition.

Symptoms

Unlike many other forms of MPS, symptoms often appear after the first year of life. A decline in learning ability typically occurs between ages 2 and 6. The child may have normal growth during the first few years, but final height is below average. Delayed development is followed by deteriorating mental status.

Other symptoms include:

  • Behavioral problems
  • Coarse facial features
  • Diarrhea
  • Full lips
  • Heavy eyebrows that meet in the middle of the face above the nose
  • Sleep difficulties
  • Stiff joints that may not extend fully
  • Walking problems

Exams and Tests

A physical exam may show signs of liver and spleen swelling. An eye exam will show clear corneas, unlike the cloudy corneas seen in persons with Hurler syndrome (MPS I H). Neurological testing will reveal signs of seizures and intellectual disability.

Urine tests will be done. Persons with Sanfilippo syndrome have large amounts of a mucopolysaccharide called heparan sulfate in the urine.

Other tests may include:

  • Blood culture
  • Echocardiogram
  • Skin fibroblast culture
  • X-rays of the bones

Treatment

There is no specific treatment available for Sanfilippo syndrome.

Support Groups

Additional information and resources are available from the National MPS Society .

Outlook (Prognosis)

The syndrome causes significant neurological symptoms, including severe intellectual disability. IQs may be below 50. Most persons with Sanfilippo syndrome live into their teenage years. Some patients live longer, while others with severe forms die at an earlier age. Symptoms appear most severe in persons with type A Sanfilippo syndrome.

Possible Complications

  • Blindness
  • Inability to care for self
  • Intellectual disability
  • Nerve damage that slowly gets worse and eventually requires wheelchair use
  • Seizures

When to Contact a Medical Professional

Call your health care provider if your child does not seem to be growing or developing normally.

Call for an appointment with your health care provider if you plan to have children and you have a family history of Sanfilippo syndrome.

Prevention

Genetic counseling is recommended for prospective parents with a family history of Sanfilippo syndrome. Counseling is also recommended for families who have a child with Sanfilippo syndrome, to help them understand the condition and possible treatments. Prenatal testing is available.

References

Wraith JE. Mucopolysaccharidoses and oligosaccharidoses. In: Saudubray J-M, van den Berghe G, Walter JH, eds. Inborn Metabolic Diseases: Diagnosis and Treatment. 5th ed. New York, NY: Springer; 2012:chap 40.

Updated: 5/7/2013

Chad Haldeman-Englert, MD, FACMG, Wake Forest School of Medicine, Department of Pediatrics, Section on Medical Genetics, Winston-Salem, NC. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.


©  UPMC | Affiliated with the University of Pittsburgh Schools of the Health Sciences
Supplemental content provided by A.D.A.M. Health Solutions. All rights reserved.

For help in finding a doctor or health service that suits your needs, call the UPMC Referral Service at 412-647-UPMC (8762) or 1-800-533-UPMC (8762). Select option 1.

UPMC is an equal opportunity employer. UPMC policy prohibits discrimination or harassment on the basis of race, color, religion, ancestry, national origin, age, sex, genetics, sexual orientation, marital status, familial status, disability, veteran status, or any other legally protected group status. Further, UPMC will continue to support and promote equal employment opportunity, human dignity, and racial, ethnic, and cultural diversity. This policy applies to admissions, employment, and access to and treatment in UPMC programs and activities. This commitment is made by UPMC in accordance with federal, state, and/or local laws and regulations.

Medical information made available on UPMC.com is not intended to be used as a substitute for professional medical advice, diagnosis, or treatment. You should not rely entirely on this information for your health care needs. Ask your own doctor or health care provider any specific medical questions that you have. Further, UPMC.com is not a tool to be used in the case of an emergency. If an emergency arises, you should seek appropriate emergency medical services.

For UPMC Mercy Patients: As a Catholic hospital, UPMC Mercy abides by the Ethical and Religious Directives for Catholic Health Care Services, as determined by the United States Conference of Catholic Bishops. As such, UPMC Mercy neither endorses nor provides medical practices and/or procedures that contradict the moral teachings of the Roman Catholic Church.

© UPMC
Pittsburgh, PA, USA UPMC.com