Handbook of Genetic Counseling/Sanfilippo syndrome

Sanfilippo syndrome

Other names: Mucopolysacchardosis III, Type A, B, C, and D

 * So, it is a syndrome in which the large saccharides are not broken down properly in the lysosomes. It's a lysosomal storage deficiency.

Characteristics

 * Most common of the MPS diseases
 * Normal to fast growth 1-3 years. Slow growth after that.
 * Slow development by 1-3 years then deterioration
 * Short stature
 * Hearing loss
 * Poor gait
 * Poor speech
 * Poor behavior
 * Synophrys (joined eyebrows)
 * Mild cardiac involvement
 * Clear corneas
 * Sleep disturbances
 * Upper respiratory tract infections
 * Many die of pneumonia (10-20 years)

Genetics

 * Autosomal recessive in all types
 * Sanfilippo A = defect in heparan N-sulfatase
 * Sanfilippo B = deficiency in N-acetyl-alpha-delta glucosaminidase
 * Sanfilippo C = deficiency of acetyl-CoA: alpha-glucosaminide-N-acetyltransferase
 * Sanfilippo D = deficiency of N-acetyl-alpha-delta glucosaminide-6-sulfatase

Diagnosis

 * By clinical features mentioned above (same for all four types except type D)
 * Overactivity
 * Destructive tendencies
 * Weakness in all extremities
 * Presence of excess heparan sulfate in the urine

Resources

 * National MPS Society
 * 102 Aspen Drive


 * Downingtown, PA 19335
 * (610) 942-0100
 * http://mpssociety.org/index.htm