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I-Cell Disease (Mucolipidosis Type II) Follow-up

  • Author: Karl S Roth, MD; Chief Editor: Luis O Rohena, MD  more...
Updated: Aug 21, 2015


Respiratory infections, such as pneumonia and otitis media, frequently recur in patients with I-cell disease.

Depending on the extent of neurologic compromise, aspiration pneumonia can also become a recurrent problem.

Congestive heart failure results from chronic valvular insufficiency.

Atlantoaxial instability can develop because of abnormally shaped cervical vertebrae. If this occurs, patients should be monitored and, eventually, surgically stabilized to avoid the risk of spinal cord injury.



Psychomotor retardation is progressive, and patients with cardiopulmonary complications usually die by age 10 years.


Patient Education

Families must be educated about the genetic basis of this disorder, including recurrence risks, identification of carriers, and the availability of prenatal diagnosis for future at-risk pregnancies.

Contributor Information and Disclosures

Karl S Roth, MD Retired 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 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, Southern Society for Pediatric Research

Disclosure: Nothing to disclose.


Margaret M McGovern, MD, PhD Professor and Chair of Pediatrics, Stony Brook University School of Medicine

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

Disclosure: Nothing to disclose.

William B Rizzo, MD Professor, Department of Pediatrics, University of Nebraska Medical Center

William B Rizzo, MD is a member of the following medical societies: American Society of Human Genetics, Society for Inherited Metabolic Disorders

Disclosure: Nothing to disclose.

Specialty Editor Board

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 School of Medicine

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

Disclosure: Nothing to disclose.

Chief Editor

Luis O Rohena, MD Chief, Medical Genetics, San Antonio Military Medical Center; Assistant Professor of Pediatrics, Uniformed Services University of the Health Sciences, F Edward Hebert School of Medicine; Assistant Professor of Pediatrics, University of Texas Health Science Center at San Antonio

Luis O Rohena, MD is a member of the following medical societies: American Academy of Pediatrics, American Chemical Society, American College of Medical Genetics and Genomics, American Society of Human Genetics

Disclosure: Nothing to disclose.

Additional Contributors

Edward Kaye, MD Vice President of Clinical Research, Genzyme Corporation

Edward Kaye, MD is a member of the following medical societies: American Academy of Neurology, Society for Inherited Metabolic Disorders, American Society of Gene and Cell Therapy, American Society of Human Genetics, Child Neurology Society

Disclosure: Received salary from Genzyme Corporation for management position.


The authors and editors of Medscape Reference gratefully acknowledge the contributions of previous author Grace Lee, MD, to the original writing and development of this article.

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Profile view of 3-year-old with I-cell disease. Growth ceased more than one year earlier. Note small orbits, proptotic eyes, full and prominent mouth caused by gingival hypertrophy, short and broad hands, stiffening of small hand joints, prominent abdomen with umbilical hernia, and limited extension of the hips and knees.
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