Sandhoff disease is a rare, genetic, lipid storage disorder resulting in the progressive deterioration of the central nervous system.
Alternate Names: Gangliosidosis GM2 type II, Gangliosidosis Beta Hexosaminidase B Deficiency, Hexosaminidases A and B Deficiency.
Sandhoff disease is caused by a mutation (defect) in the HEXB gene. This defect causes a deficiency of the enzyme beta-hexosaminidase, which results in the accumulation of certain fats (lipids) in the brain and other organs of the body.
Infantile form: Onset of the disorder usually occurs at 6 months of age. Infants with Sandhoff disease typically appear normal until the age of 3 to 6 months, when development slows and muscles used for movement weaken.
Sandhoff disease symptoms may include:
Startle reaction to sound
Progressive mental and motor deterioration
Macrocephaly (an abnormally enlarged head)
Cherry-red spots in the eyes
Myoclonus (shock-like contractions of a muscle)
Frequent respiratory infections
Doll-like facial appearance
An enlarged liver and spleen.
Onset by 6 months of age and positive gene testing confirm the diagnosis of this disease. Individuals and carriers of Sandhoff disease can be identified by a simple blood enzyme analysis test that measures HEXB activity.
There is no specific treatment for Sandhoff disease.
Supportive treatment includes proper nutrition and hydration and keeping the airway open. Anticonvulsants may initially control seizures. In other ongoing studies, a small number of children have received an experimental treatment using transplants of stem cells from umbilical cord blood. Although these limited trials have not yet produced a treatment or cure, scientists continue to study these and other investigational approaches.
The prognosis for individuals with Sandhoff disease is poor. In the Infantile form, affected children usually do not survive past the age of 3 and death is generally caused by respiratory infections.