Mucopolysaccharidosis type I
- MPS 1
- Attenuated MPS I (subtype, includes Hurler-Scheie and Scheie syndrome)
- Severe MPS I (subtype, also known as Hurler syndrome)
- Hurler syndrome (subtype)
- Hurler-Scheie syndrome (subtype)
Your QuestionI would like general information on mucopolysaccharidosis I (MPS I). My grandson was recently diagnosed with this condition and is currently undergoing enzyme therapy. Is a person with MPS I less likely to have brain damage if a bone marrow transplant is performed early?
We have identified the following information that we hope you find helpful. If you still have questions, please contact us.
Questions on this page
- What is mucopolysaccharidosis I?
- What are the symptoms of mucopolysaccharidosis I (MPS I)?
- Why are there different names for mucopolysaccharidosis I (MPS I)?
- What causes mucopolysaccharidosis I (MPS I)?
- How is mucopolysaccharidosis I (MPS I) inherited?
- What is autosomal recessive inheritance?
- What treatment is available for mucopolysaccharidosis I (MPS I)?
- Is a person with mucopolysaccharidosis I (MPS I) less likely to have brain damage if a bone marrow transplant is performed early?
- How can I learn about research involving mucopolysaccharidosis I (MPS I)?
- Are there any advocacy organizations for individuals and families with mucopolysaccharidosis I (MPS I)?
MPS I was once divided into three separate syndromes: Hurler syndrome, Hurler-Scheie syndrome, and Scheie syndrome, listed from most to least severe. Because no biochemical differences have been identified and the clinical findings overlap, the condition is now divided into two subtypes, severe MPS I and attenuated MPS I. People with severe MPS I typically have an earlier onset of symptoms, a decline in intellectual function, and a shorter lifespan. Although there is no cure for MPS I, bone marrow transplant and enzyme replacement therapy are treatment options that may help manage the symptoms of this condition.
The signs and symptoms of MPS I are not present at birth, but they begin to appear during childhood. People with severe MPS I develop the features of this condition earlier than those with attenuated MPS I. The following list includes the most common signs and symptoms of MPS I.
- Enlarged head, lips, cheeks, tongue, and nose
- Enlarged vocal cords, resulting in a deep voice
- Frequent upper respiratory infections
- Sleep apnea
- Hepatosplenomegaly (enlarged liver and spleen)
- Umbilical hernia
- Inguinal hernia
- Hearing loss
- Recurrent ear infections
- Corneal clouding
- Carpal tunnel syndrome
- Narrowing of the spinal canal (spinal stenosis)
- Heart valve abnormalities, which can lead to heart failure
- Short stature
- Joint deformities (contractures)
- Dysostosis multiplex (generalized thickening of most long bones, particularly the ribs)
The U.S. National Institutes of Health, through the National Library of Medicine, developed ClinicalTrials.gov to provide patients, family members, and members of the public with current information on clinical research studies. Currently, 8 clinical trials are identified as enrolling individuals with mucopolysaccharidosis I. Click here for a list of these trials. After you click on a study, review its "eligibility" criteria to determine its appropriateness. Use the study’s contact information to learn more. Check this site often for regular updates.
You can also contact the Patient Recruitment and Public Liaison (PRPL) Office at the National Institutes of Health (NIH). We recommend calling the toll-free number listed below to speak with a specialist, who can help you determine if your grandson is eligible for any clinical trials.
Patient Recruitment and Public Liaison Office
NIH Clinical Center
Bethesda, Maryland 20892-2655
Web site: http://clinicalcenter.nih.gov/
National MPS Society
4220 NC Hwy 55, Ste.140
Durham, NC 27713
Web site: http://www.mpssociety.org
Society for Mucopolysaccharide (MPS) Diseases
MPS House Repton Place White Lion Road
United Kingdom HP7 9LP
Phone: (+44) 0845 389 9901
Web site: http://www.mpssociety.co.uk
- Clarke LA, Heppner J. Mucopolysaccharidosis Type I. GeneReviews. October 31, 2002; http://www.ncbi.nlm.nih.gov/books/NBK1162/.
- Mucopolysaccharidosis type I. Genetics Home Reference (GHR). December 2012; http://ghr.nlm.nih.gov/condition/mucopolysaccharidosis-type-i.
- What are the different ways in which a genetic condition can be inherited?. Genetics Home Reference Web site. January 25, 2016; http://ghr.nlm.nih.gov/handbook/inheritance/inheritancepatterns.
- Hurler's Syndrome and Transplant. National Marrow Donor Program Web site. http://www.marrow.org/PATIENT/Undrstnd_Disease_Treat/Lrn_about_Disease/Metabolic_Storage/Hurler_and_Tx/index.html. Accessed 7/15/2008.