Metabolic defect: Type A - heparan N-sulfatase (sulfamidase) deficiency; Type B - alpha-N-acetyl-glucosaminidase deficiency; Type C - acetyl-coa: alpha glucosaminide acetyltransferase deficiency; Type D - galactose 6-sulfatase (N-acetyl-glucosamine 6-sulfatase) deficiency Other glycosaminoglycans metabolism diseases (mucopolysaccharidoses): MPS I | MPS II | MPS IV | MPS VI | MPS VII

Current page: MPS III Select Another Disease Select disease Acid sphingomyel. def. Aspartylglycosaminuria Cystinosis Fabry disease Farber disease Fucosidosis type I Fucosidosis type II Galactosialidosis Gaucher type I Gaucher type II Gaucher type III GM1 gangliosidosis I GM1 gangliosidosis II GM1 gangliosidosis III Infantile sialic acid Krabbé disease Mannosidosis Metachr. leukodys. I Metachr. leukodys. II Metachr. leukodys. III MPS I MPS II Hunter MPS III Sanfilippo MPS IV Morquio MPS VI Maroteaux-Lamy MPS VII Sly Mucolipidosis II Mucolipidosis III Mucolipidosis IV Neuro ceroid lipof I Neuro ceroid lipof II Neuro ceroid lipof III Neuro ceroid lipof IV Pompe disease Pycnodysostosis Salla disease Sandhoff type I Sialidosis type I Sialidosis type II Tay-Sachs type I Tay-Sachs type II Tay-Sachs type III

Enzyme deficiency results in progressive accumulation of the glycosaminoglycan (GAG) heparan sulfate.

Coarse facial features		Hepatosplenomegaly		Hernia		Coarse hair

Image Credits: Coarse facial features courtesy of The National MPS Society, Inc. Hernia courtesy of Atlas of Metabolic Diseases, Arnold, 1998. Coarse hair courtesy of Emil Kakkis, MD, PhD.

Progressive disorder with multiple organ and tissue involvement. No clear clinical difference among the four types, although type A is most severe with earlier onset, more rapid progression of symptoms, and shorter survival. Onset is variable but usually obvious between 2 and 8 years of age. Progressive and severe central nervous system degeneration, mild somatic disease. Survival into the 3rd decade. Airway obstruction and cardiac failure are the most common direct causes of death.

Inheritance pattern: autosomal recessive

Incidence:^[4]

Diagnosis: enzyme assay

Conditions with similar presentations:

Management: bone marrow transplantation in some cases

Other medical care: symptom management

Hyperactivity with aggressive behavior

Delayed speech development

Severe hearing loss

Seizures

Profound mental retardation

Minimal skeletal involvement

Mild joint stiffness

Recurrent and sometimes severe diarrhea

Delayed development

Early onset of puberty

Coarse hair

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1. Neufeld EF, Muenzer J. The mucopolysaccharidoses. In: The Metabolic Bases of Inherited Disease. New York: mcgraw Hill, 2001; 3421-3452.

2. Clarke LA. Clinical diagnosis of lysosomal storage diseases. In: Applegarth DA, Dimmick JE, JG Hall. Organelle Diseases: Clinical Features, Diagnosis, Pathogenesis and Management. London: Chapman and Hall 1997; 37-71.

3. A guide to understanding Sanfilippo Syndrome. The National MPS Society, Inc.; 2000.

4. Meikle PJ, Hopwood JJ, Clague AE, Carey WF. Prevalence of Lysosomal Storage Disorders. JAMA. 1999; 281: 249-254.