Genetics of Mucopolysaccharidosis Type II Treatment & Management

  • Author: Nancy E Braverman, MS, MD; Chief Editor: Bruce Buehler, MD   more...
 
Updated: Aug 5, 2011
 

Medical Care

Although no curative treatment for lysosomal storage disorders is available, numerous treatment options are becoming available to improve the quality of life in these patients. The relevant enzyme (iduronate sulfatase [IDS] in the case of mucopolysaccharidosis type II [MPS II]) can be given in the form of enzyme replacement therapy (ERT) or by bone marrow transplantation (BMT). Factors that affect outcome include the type of MPS, the donor genotype (in the case of BMT), and the age and degree of clinical involvement at the start of therapy or transplantation.

In order to identify individuals that might benefit from treatment before the onset of irreversible organ damage, newborn screening for these disorders is being developed.[28] Gene therapy is a promising but inadequately developed modality of treatment. Difficulties with vector selection and efficiency of delivery persist; thus, this therapy is still in the early stages of development.

  • BMT
    • In 16 children with Hunter syndrome who have undergone BMT, marked deterioration in mental retardation continued in 15.[29] All 15 children had intelligence quotients that fell below 50. Some of these children did have improvement in their somatic symptoms, with a decrease in the coarsening of their face and hair and an increase in the range of motion in their joints. The hearing deficits may not improve after BMT.
    • In addition to the study of BMT, the use of umbilical cord blood transplantation from an unrelated donor has been attempted at least once.[30]
  • ERT: See Medication.
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Surgical Care

  • Many children with Hunter syndrome require surgical intervention for complications of their disorder. These include intervention for chronic hydrocephalus, nerve entrapment (carpal tunnel syndrome), abdominal wall hernias, tracheostomy, and joint contractures.
  • Individuals with Hunter syndrome should undergo anesthesia at a center with experienced personnel.
  • Problems can occur with airway management, postobstructive pulmonary edema, and reactive airway disease.
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Consultations

  • Care for the patient with Hunter syndrome involves a multidisciplinary approach and includes pediatricians, neurologists, orthopedists, otolaryngologists, ophthalmologists, and occupational and physical therapists, as well as geneticists and counselors.
  • The recognition and diagnosis of MPS II was recently reviewed.[31]
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Contributor Information and Disclosures
Author

Nancy E Braverman, MS, MD  Associate Professor, Department of Human Genetics, McGill University

Nancy E Braverman, MS, MD is a member of the following medical societies: Alpha Omega Alpha, American Society of Human Genetics, Society for Inherited Metabolic Disorders, and Society for the Study of Inborn Errors of Metabolism

Disclosure: Nothing to disclose.

Coauthor(s)

Cydney L Fenton, MD  Director, Center for Diabetes and Endocrinology, Akron Children's Hospital

Cydney L Fenton, MD is a member of the following medical societies: American Academy of Pediatrics, American Diabetes Association, Endocrine Society, and Pediatric Endocrine Society

Disclosure: Nothing to disclose.

Mary Kay Conover-Walker, MSN, PNP  Pediatric Nurse Practioner, Institute of Genetic Medicine, Johns Hopkins Hospital

Mary Kay Conover-Walker, MSN, PNP is a member of the following medical societies: American Academy of Allergy Asthma and Immunology and Association of Clinical Research Professionals

Disclosure: Nothing to disclose.

Specialty Editor Board

Karl S Roth, MD  Professor and Chair, Department of Pediatrics, Creighton University School of Medicine

Karl S Roth, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Pediatrics, American College of Nutrition, American Pediatric Society, American Society for Clinical Nutrition, American Society of Nephrology, Association of American Medical Colleges, Medical Society of Virginia, New York Academy of Sciences, Sigma Xi, Society for Pediatric Research, and Southern Society for Pediatric Research

Disclosure: Nothing to disclose.

Mary L Windle, PharmD  Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Nothing to disclose.

Margaret M McGovern, MD, PhD  Professor and Chair of Pediatrics, Stony Brook University, New York

Margaret M McGovern, MD, PhD is a member of the following medical societies: American Academy of Pediatrics and American Society of Human Genetics

Disclosure: Genzyme Grant/research funds PI

Daniel Rauch, MD, FAAP  Director, Pediatric Hospitalist Program, Associate Professor, Department of Pediatrics, New York University School of Medicine

Daniel Rauch, MD, FAAP is a member of the following medical societies: Ambulatory Pediatric Association, American Academy of Pediatrics, and Society of Hospital Medicine

Disclosure: Baxter Honoraria Consulting

Chief Editor

Bruce Buehler, MD  Professor, Department of Pediatrics and Genetics, Director RSA, University of Nebraska Medical Center

Bruce Buehler, MD is a member of the following medical societies: American Academy for Cerebral Palsy and Developmental Medicine, American Academy of Pediatrics, American Association on Mental Retardation, American College of Medical Genetics, American College of Physician Executives, American Medical Association, and Nebraska Medical Association

Disclosure: Nothing to disclose.

Acknowledgments

The authors and editors of Medscape Reference gratefully acknowledge the contributions of previous authors William Rogers, MD, and Vinayak Kottoor, MD, to the original writing and development of this article.

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