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

      Notes

      The information in this outline was last updated in 2000.

      Last modified on 18 June 2006, at 11:17