Amaurotic familial idiocy

Alternative names:

batten disease; Jansky-Bielschowsky; Kufs' disease; lipofuscinosis; Spielmeyer-Vogt

Definition:

An inherited disorder that derives its name from the three major features of the disease, blindness (amaurotic), severe retardation (idiocy), and its tendency to run in families.

Causes, incidence, and risk factors:

Amaurotic familial idiocy is inherited as an autosomal recessive trait. If both parents carry the trait, the statistical incidence (results that could appear in their offspring) will be:

• 25% -- one of four children will have the disease.
• 50% -- two of four children will be entirely normal but be carriers of the trait.
• 25% -- one of four children will be entirely normal and NOT be a carrier.

Amaurotic family idiocy involves excessive storage of lipofuscin. In excessive quantities, this material damages the nervous tissue. The disorder may become evident some time after the second year of life, in the teens or as an adult. Children develop muscle incoordination (ataxia) walking abnormalities or disturbances, visual problems, retardation and seizures. Later appearance of the disease is associated with somewhat less severe debility.