Denouement and Discussion
Tay-Sachs Disease
Manifestations
The characteristic cherry-red spots of Tay-Sachs disease were first described in 1881 by Warren Tay, a British ophthalmologist, in a 1-year-old child with mental and physical retardation.1 Bernhard Sachs, a neurologist, coined the term familial amaurotic idiocy for this disorder and described the typical morphologic feature of the disease: distended cytoplasm of the neurons and ballooning of their dendrites. In the 1930s, Ernst Klenk, a biochemist, used the name gangliosides to describe the glycolipid accumulation in ganglion cells characteristic of this disease.1Tay-Sachs Disease, now referred to as GM2 gangliosidosis, type 1, has a classic progression. Affected infants appear normal at birth. The earliest signs, beginning at age 3 to 5 months, are mild motor weakness and myoclonic jerks associated with sharp noises. Most often, these signs are not recognized by the parents, except in retrospect. Between ages 6 and 10 months, there is a progressive loss of motor function with weakness, hypotonia, poor head control, and decreased attentiveness to surroundings. The exaggerated response to auditory stimuli suggests hyperacusis. Visual signs, such as unusual eye movements and episodes of staring, or concerns about decreased visual acuity, may lead to ophthalmologic consultation, the discovery of the cherry-red spots (Figs 1 and 2), and ultimately the diagnosis of GM2 gangliosidosis.