Gerstmann-Sträussler-Scheinker syndrome masquerading as multiple sclerosis.

Gerstmann-Sträussler-Scheinker syndrome (GSS) is a rare degenerative disorder of the central nervous system that belongs to the family of human spongiform encephalopathies, or prion diseases. GSS is almost always inherited and mostly carried in an autosomal dominant pattern. Nevertheless, GSS is genetically and phenotypically heterogeneous; among the different prion diseases GSS has the longest clinical course thereby has the potential to mimic the clinical course of different neurological disorders.