MPS 1

Mucopolysaccharidosis type 1 (MPS 1) is a very rare genetic disorder that can cause stiffened joints, abnormally shaped bones, a protruding belly, frequent ear infections and bad vision. MPS 1 can affect males and females across all races.

MPS 1 Overview, Symptoms and Diagnosis

Disease Overview

Mucopolysaccharidosis 1 (MPS 1) is a rare, inherited lysosomal storage disorder caused by the deficiency of an enzyme (α-L-iduronidase) in the lysosomes of certain cells. Deficiency of this enzyme results in the accumulation of a waste materials (called glycosaminoglycans, or GAG) in cells throughout the body.

MPS 1 has historically be known as Hurler, Hurler-Scheie, and Scheie syndromes. The disease has a wide spectrum of symptoms which vary in severity. Clinical manifestations of MPS I include enlarged liver and spleen, abnormally shaped bones, coarse facial features, and severe joint disease. Hearing, vision, respiratory, and cardiovascular functions are all affected. Joint mobility is typically severely reduced.

Major Signs and Symptoms

• Joint Stiffness
• Skeletal deformities
• Coarse facial features
• Enlarged liver and spleen
• Corneal clouding
• Obstructive airway disease
• Recurrent ear and nose infections

Other Diseases With Similar Symptoms

Diagnosis is often delayed since signs and symptoms may be shared with other disorders. However, early diagnosis and treatment are critical to optimizing outcomes. Some common differential diagnoses include:

• Juvenile rheumatoid arthritis
• Rheumatoid arthritis
• Idiopathic rheumatoid arthritis
• Other mucopolysaccharidoses
• Multiple sulfatase deficiency

Diagnosis

MPS 1 can be diagnosed by a blood test which measures enzyme activity in the blood.

For more information on how to be tested for MPS 1 or for information on genetic counselling please contact:

Division of Human Genetics
National Health Laboratory Service
+21 11 489 9223/4

or

Division of Human Genetics
University of Cape Town
+27 21 406 6304