clinical features
Last reviewed 01/2018
The first sign of Tay-Sachs disease is usually an abnormal startle reflex to sound consisting of extension and myoclonus in the first weeks of life.
Early development is normal but between the ages of 4 and 6 months the child does not sit up, loses head control and takes no interest in the environment.
The infant is blind by the end of the first year. Fundoscopy reveals a cherry-red spot at the macula. Retinal artery occlusion and Niemann-Pick disease should be excluded in these circumstances.
After approximately 3 years the child becomes demented, blind, cachexic, and adopts a decerebrate posture.
mental retardation (term that has been replaced by intellectual developmental disorder)