Sanfilippo syndrome

Alternative names:

mucopolysaccharidosis III (A - B - C)

Definition:

Sanfilippo syndrome is one of the hereditary mucopolysaccharide storage diseases and is characterized by the absence of the enzyme N-acetyl-a-D-glucosaminidase and the excretion of heparan sulfate in the urine.

Causes, incidence, and risk factors:

Sanfilippo syndrome is transmitted as an autosomal recessive trait. It is possibly the most common of the mucopolysaccharide storage diseases. Sanfilippo syndrome has a relatively late onset rather than during the first year of life. It shares, in common with most of the mucopolysaccharide storage diseases, coarse facial features, decreased mental development that progresses to severe mental retardation, stiff joints, gait disturbances, speech disturbances, and behavioral problems. Unlike Hurler syndrome the cornea is clear, the condition is not as unrelenting, and survival times are longer, often into the twenties or later.