Explanation
MUCOPOLYSACCHARIDOSES
• Defective activity of the lysosomal enzymes, which blocks degradation of
mucopolysaccharides and leads to abnormal accumulation of heparan sulfate,
dermatan sulfate, and keratan sulfate.
• Seven types:
• Hurler syndrome (MPS IH)
• Hurler-Scheie syndrome (MPS I-H/S)
• Scheie syndrome (MPS IS)
• Hunter syndrome (MPS II)
• Sanfilippo syndrome (MPS III)
• Morquio syndrome (MP IV)
• Maroteaux-Lamy syndrome (MPS VI)
• Sly syndrome (MPS VII)
• All are autosomal recessive except type II (Hunter syndrome) which is Xlinked recessive.Type I = Hurler syndrome. *
• Type IV is associated with normal intelligence
Clinical features
Patients with MPS have normal development initially, with abnormalities appearing in
infancy or later in childhood.
• CNS disease – Hydrocephalus; cervical spine myelopathy
• Cardiovascular disease – Angina; valvular dysfunction; hypertension;
congestive heart failure
• Pulmonary disease – Airway obstruction, potentially leading to sleep apnea,
severe respiratory compromise, or cor pulmonale
• Ophthalmologic disease – Corneal clouding; glaucoma; chronic papilledema;
retinal degeneration
• Hearing impairment – Deafness
• Musculoskeletal disease – Short stature; joint stiffness; symptoms of
peripheral nerve entrapment