GM1 Gangliosidosis - Type III (Adult Form)
Etiology and Pathogenesis
Enzyme deficiency results in accumulation of GM1 gangliosides in the central nervous system (especially the basal ganglia) and galactosyl oligosaccharides. Keratan-sulfate degradation products accumulate in somatic cells (visera). With type III, the deposition of GM1 gangliosides is less extensive than with the other two types. Deposition of substances in the peripheral tissues is also less extensive in type III (than in I and II).
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Clinical Description and Progression/Prognosis  Late onset (teens) Lack of visceral involvement Death occurs after 20 years of age (up to 4th decade) Inheritance pattern: autosomal recessive Incidence (all types): generally unknown, but unusually high incidence of 1 case per 3700 live births has been reported in the population of Malta. [1] Diagnosis: enzyme assay Conditions with similar presentations: I-Cell Disease (Mucolipidosis Type II); Mucolipidosis Type I (Alpha-Neuraminidase Deficiency-Sialidosis); Mucopolysaccharidosis Type I (Hurler) Management: no disease-specific treatment available Other medical care: symptom management
Gait disturbances (ataxia) Dysarthria Spasticity Slowly progressive dystonia affecting the face and limbs Mild mental impairment
1. Tegay, David. “GM1 Gangliodosis”. www.emedicine.com/ped/topic2891.htm Accessed August 2004. |
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